TK-890 Amateur Radio Mod

Over the past weekend a friend of mine asked if I would help him convert his Kenwood TK-890 mobile to work on the ham bands.  I wasn't sure how successful we'd be, since most every online search came up with at best little information or at worst flat out statements saying "Nope, can't be done."  As it turns out, it can be done.  Kudos to Tim K for his notes posted to Radio Reference which gave enough hints to make this happen. 

In general this is how it went.  My friend wanted his radio to work on the Bay-Net repeater system, which operates 443.225 with a +5 MHz TX split.  TX was fine, but RX was giving a steady "beep-beep-beep..." which indicates PLL unlock.

In the PLL section, under the copper foil, are three adjustment pots: A = TC302, B = TC303, and C = TC301.  (Don't ask why they're out of order.)  According to the Service Manual, Pot A sets the PLL for the low end of the receiver range, Pot B sets the high end of the receiver range, and Pot C sets the TX PLL.  The goal is to monitor test point CV with a voltmeter and adjust for minimum voltage during RX and TX.  This requires re-programming the radio's test frequencies to match the band of interest, so you'll need the KPG software and cable. 

Once we had the PLL voltages minimized for RX and TX, I found that the radio's TX frequency was way off, so a frequency alignment was needed.  This again required the KPG software - for some reason we couldn't get the radio into Panel Test/Tune via the control head.  It was easy enough with the KPG, once we realized you need to press "Enter" to lock the modified value. 

Other things like adjusting the BPF and checking deviations should be done.  In the end, the conversion was very easy and the radio is working well on the UHF amateur band.

JT65 Articles from CQ Magazine

Last year (October and November 2010) I co-authored with Tomas NW7US a two-part article "Communicating Under the Noise" about JT65A on HF which was published in CQ Magazine.  Thanks to Rich Moseson for agreeing to make the articles available in digital form.  PDF copies of the articles can be obtained here: Download (PDF)

Enjoy.

Pacificon 2010 Wrap Up

This past weekend the Mount Diablo Amateur Radio Club hosted ARRL Pacificon at the San Ramon Marriott.  I was glad to see the event back this year, after last year's debacle which forced the organizers to move the event to Reno in conjunction with EMCOMM West.

This year's event was well-attended.  There were some great presentations, I got a chance to see some folks I don't often see, and I was given the chance to speak twice; including delivering the final keynote on Sunday.

I promised several people that I would post my presentations, so here they are:

   Weak Signal HF with JT65A

   Ham Radio Must Die!

An example of why amateur radio is failing to attract young people

I follow various hams on Twitter and in blogs. Some because they're friends, some because they're part of my local radio community, and some just because I like what they have to say. There's another smaller group I follow, which is people I tend to not agree with. In the same way that conservatives will listen to NPR and watch CNN as a way to better understand and counter the liberal/socialist viewpoint, reading these people's tweets and blogs helps me understand why amateur radio continues to slide into obscurity.

Mike WA4D's "MEWCOMM" blog and Twitter commentary is one which I typically don't agree with. His position on matters relating to amateur radio are highly representative of a mindset which pervades the hobby, and which I believe is ultimately counter-productive to the hobby's evolution. I will use Mike's writings as proxies for opinions held by others, so apologies to Mike in advance; this is not intended to be a personal attack at you. To be fair; I like and agree strongly with Mike's perspectives on politics and foreign policy, but his judgmental attitude towards no-code hams (i.e. those who have not learned Morse Code or "CW" in the parlance) happens to be a perfect example of why amateur radio is failing to attract young people into the hobby. A sampling of Mike's comments include:

• People who don't know how CW "are not real hams".
• Removal of the CW testing requirement was equivalent to "affirmative action" or a "back door".
• CW defines the "soul of the hobby" and "defines what a real ham is in the 21st century".

In 2006 the FCC was in the process of implementing WRC-03 recommendations which would later eliminate CW testing as a requirement for amateur radio licensing. I filed comments with the FCC during the comment period in support of this decision, in which I asked "Is the true measure of technical prowess the ability to understand what amounts to a language?" Indeed; my experience is that hams who know code are no better or worse operators or technologists than hams who don't know code. Some of the smartest hams I know -- hams who have contributed real value in the application of computing technology to radio -- are Extra-class hams who never learned Morse Code. My opinion? These people, and the technology they're developing, will truly define amateur radio in the 21st century.

Mike recently wrote that no-code hams "know not of the 'thrill of recognition'", which I infer to mean that they're not real hams because they're never experienced the "satori" moment of completing their first Morse Code contact. Having experienced the "thrill of recognition" for CW and other modes I can say that while the satori moment for CW is indeed exciting, it's no stronger or more "real" than the satori moment I had when I made a 10,000+ mile contact using JT65A on HF at 50 watts of power into a hand-made antenna cobbled from $2.00 worth of spare parts and wire. I remember both experiences equally well, and yet the JT65A contact is more memorable (and a source of greater pride for me) because I did it using a new (at the time) mode on jury-rigged hardware. But following Mike's logic I guess this wasn't a real accomplishment because it involved use of a computer, and at the time I didn't know how to send & receive CW..?

Amateur radio is a "big tent" hobby which offers something for everyone. If the hobby were healthy, growing, and not in danger of obsolescence I would say "Live and let live" and be done with it. But opinions such as "people who don't know or use CW are not real hams" are too prevalent among a majority of hams, with the end result being that bright young people who might want to explore amateur radio's application to computers and digital communication are scared away by older hams who insist on defining "real radio" in terms that they can understand.

The danger is that, as older hams pass on and are not replaced by younger hams, we will reach a point where the government decides that amateur radio spectrum can be put to better use. ARRL or not, the ham population will be too small to defend our allocation, and combined with decreasing relevance and value to emergency communications we will eventually lose our spectrum. Proficiency in CW and adherence to traditions will not solve this problem and help us keep our spectrum. The only solution is to open our minds, embrace change, and get over this self-defeating need to hold up 100+ year old technology as the gold standard against which new technology must compare.

The crux of the problem is that the prevailing majority has defined amateur radio and its reverence of traditions as an immutable core. This is horribly wrong and ultimately self-defeating. We should instead be seeking ways that encourage the applying of amateur radio to new technologies, and in doing so continuously finding new relevance and recruiting new hams. "Real hams" are those that are creating innovative technology which applies amateur radio to technology, such as Chris K6DBG's hack that converts a Wi-Fi router into an APRS receiver. Speaking the "language" of Morse Code isn't proof of technical ingenuity, doesn't prove that a ham is innovative or intelligent, and arrogantly judging hams based on their ability (or not) to use CW drives away new recruits and will NOT save our hobby.

SO2R -- The hard way

This past weekend I had the privilege to be a guest operator for the Radio Club of America on their special event station W2RCA, celebrating the 100th anniversary of the RCA. The station was co-located with the anniversary event in Washington DC, and I wasn't able to attend in person, so the operation was handled using remote PC access and VOIP software, similar to the setup which I described back in late 2007.

A problem with remote setups is that they require a fast Internet connection to work well; the primary challenge being the speed (or lack thereof) at which you can switch from receive to transmit and back again. Because the W2RCA special event station was scheduled to happen during the ARRL's November SSB Sweepstakes, it was decided that we would work the contest as W2RCA. Being in a contest situation meant that rapid TX/RX switching would be a must.

As it turned out the network connection between my home and the RCA event location wasn't quite fast enough for the furious pace of the contest. I was having a hard time getting the remote radio keyed quickly enough to bust the pileups. In some cases I would bust the pileup only to have the target station get frustrated because I wasn't coming back to him fast enough. Not good, not good...

Out of curiosity I turned on my home station and tuned to the same frequency as the W2RCA remote. I found that despite being separated by 2,500 miles I could hear the target station well on both radios! Not wanting to give up on the contest for lack of fast TX/RX switching I decided to try an odd twist on SO2R (Single Operator-Two Radios) setup. I activated transmit on the W2RCA remote station, muted my microphone, and plugged my headphones into my home station. Because SSB is carrier-less mode the remote radio would not transmit any power with the microphone muted.

The next time the target station called QRZ I unmuted my microphone and called him, and heard him come back to me on my home station! I was able to work several stations this way, although there were still a few challenges. First was the effort of keeping the frequency of ftwo radios in sync. Second was some of the stations I could hear clearly on my home station were outside the range of the W2RCA remote station. But in general it worked and was an interesting way to get around the slow TX/RX switching issue.

..-. .. .-. ... - -.-. --- -. - .- -.-. - <= (First Contact)

This week marked a big milestone for me; I successfully completed my first radio contact using CW aka Morse Code. It was a tough contact; conditions were bad but the guy I worked was polite and patient with me so we managed to pull it off.

I had always believed that I simply did not have an "ear" for code; it sounded like noise to me and I was never able to get past a basic understanding of the mechanics. After the amateur radio code requirement was lifted I was thankful and quickly upgraded to the highest level license. Still, in the back of my mind I felt I should make a real effort to learn code; if for no other reason than to overcome a personal limitation. (If you think I have a strong aversion to being told what to do; I have an even stronger aversion to being told what I can't do -- even if I'm the one doing the telling.) So my 2009 resolution was to learn enough code to complete a radio contact. It took me nine months, but I made it. I don't know that I will ever be a "real" CW operator, but right now I'm having fun and feeling good about my accomplishment.

I would like to thank the following people who helped make this happen for me:

• Gerald Wheeler (W6TJP) - Author of the Code Quick learning method. A great basic foundations course.
• Fabian Kurz (DJ1YFK) - Developer of the LCWO.net website. An awesome online Koch-method trainer. Did I mention it's free?
• Leon "Skip" Stem (WB4DAD) - CW operator, FISTS member, and the first entry in my CW contact logbook. Thanks for being patient with me.

You, um, expecting trouble? BIG Batteries...

Through a contact at an SF Bay Area web hosting company I recently obtained for free a set of used -- but still very strong -- UPS batteries; the Deka/Unigy 31HR5000. This hosting company offers their customers a 100% uptime guarantee which means that they can't wait for their UPS batteries to fail; they are used for a number of months and then they're replaced. Since the hosting company has to pay someone to come haul them away they're happy to see them repurposed.

These batteries aren't the typical deep-cycle marine variety you see on Field Day. They weigh 95 lbs each. Fresh from the factory they're rated at 135 amp-hours, which is about 1,800 watt-hours. My main HF rig (Kenwood TS-2000) consumes about 200 watts worst-case (when keyed on 2 meter FM, set for 100 watts) which means that using one of the Deka batteries I could leave my rig keyed-down on 146.520 FM @ 100 watts and it would remain on the air for about 9 hours.

I now have 3 of these monsters running in parallel on my home station. That's over a full day of continuous talk time. Left in receive-only mode my station will run off-grid for about 8 days.

Total cost? About $40 for some 4-gauge jumpers and misc hardware.

Bring on the zombie attack. I'm ready.

S 649 : Radio Spectrum Inventory Act

I posted this because I think Senate Bill 649 : Radio Spectrum Inventory Act (intro'd by Sen. John Kerry-Heinz, D-MA) is the first shot in a battle I've been predicting for some time; the application of populist politics towards spectrum management and allocation. You need only spend an hour tuning around with a decent all-band receiver to discover that the vast majority of spectrum is nothing but static. The real targets of this "spectrum socialism" are the big guns; broadcasters, the military, and even divisions of the government itself (such as NTIA) which has been "warehousing" spectrum for years while hypocritically requiring auction-winning licensees for cellular/PCS spectrum to demonstrate high levels of loading; i.e. subscribers.

Radio amateurs, I believe, are especially at risk from unintended consequences if this bill becomes law. I've previously blogged that many amateur radio frequencies are largely unused. Some amateur bands; such as 1.25m (aka 222 MHz) and 23cm (aka 1.2 GHz) are used only in certain regions of the US. (1.25m is popular in the Los Angeles area because 2m is so laden with bootleggers and jammers it's effectively become CB radio.) One reason for this is that the radio manufacturers are not selling equipment for these bands; the last 1.2 GHz equipment was the Kenwood TS-2000X which was introduced 9 years ago. Alinco is reported to be releasing a 1.2 GHz handheld, but that's not enough to drive adoption of the band. If the RSIA is an attempt to document usage of spectrum as a precursor to re-allocation based on purpose and usage, then 23 cm is one of the most likely targets for re-allocation once the limited use of that band becomes public knowledge. Our only hope is that the proximity of 23cm to radio astronomy likely precludes the allocation of that band to commercial use; but it could still be lost.

Equipment availability is one issue but at a higher-level the problem amateurs face with RSIA is simply that there are fewer radio amateurs than there were in the past; younger people prefer communicating via the Internet and if they do express an interest in amateur radio they're all-to-often turned off by the arrogance of a few hygiene-optional curmodgeons who tend to hang around at club meetings and hamfests complaining loudly and constantly about how the demise of Morse code testing will lead to the death of amateur radio; ignoring the fact that it's their own urine-soaked elitism that's probably a key element in keeping younger people from the hobby. So when faced with a trend towards populist politics and thus policies, a Congressional Budget Office estimate that the federal deficit may exceed $1.5 Trillion dollars, and huge swaths of amateur spectrum laying increasingly fallow as the number of amateurs continues to decline; the likelihood that the government will pull spectrum from amateurs and attempt to auction it off as a revenue source is increasingly likely. It's critical that we change the face of amateur radio (even if it means slaying a few sacred cows) in order to attract licensees or the day will come that some lawmaker will decide that it's politically low risk to start pulling spectrum from amateurs in order to pay off the deficit.

Economy takes a dive; amateur radio vendors fail to notice

You'd have to be living in a cave to not know what's going on with the economy, or at least what Washington D.C. is trying to terrify us into thinking is going on. Setting aside this Recession vs Depression debate for the moment; it's clear that the economy is struggling at some level. We're seeing home values drop sharply, credit is hard to obtain, auto dealers in some parts of the country offering 2-for-1 deals, etc. One need only visit your local Best Buy, Fry's, etc to find smoking hot deals on consumer electronic equipment. A buyer's market you say? Apparently not for amateur radio.

Recently I decided to buckle down and learn CW aka Morse Code. I've been using various tools, including a great online trainer called LCWO (Learn CW Online). I've also been using W6TJP's Code Quick; good for getting the sound-alikes for each character but my advice would be to save your money on the optional software and focus on sites like LCWO.

Needing a paddle/key in order to practice sending CW I decided to stop by Ham Radio Outlet (aka "the candy store" and buy the Bencher BY-1 for what their printed catalog said was $99. I pulled up in front of the store and the parking lot (normally full of vehicles festooned with antennae) was so empty I had a momentary thought that maybe it was a holiday and I'd just forgotten. I walked into the candy store (normally full of amateurs festooned with antennae) and was greeted by one lonely salesman. Recession? Depression? Clearly business is slow.

Inquiring about the Bencher paddle I found it was in stock...and that it cost $109. Ex-squeeze me? Catalog says $99. Yes, but the price went up. Since when? Since the catalog was last printed, apparently. I see... So other retailers are slashing prices, people are spending less, your store is completely empty for the first time I can recall...and you're raising prices.

To his credit my friend gave me the catalog price. Normally I'd also get a discount for being a member of the Cactus Intertie group, but not this time. It started me thinking that I've not really seen prices fall on amateur radio equipment the same way that mass-market consumer electronics have fallen. For example; I've been saying that I'll buy an IC-7000 once the sale price drops below $1,000. And yet the price remains above $1,300 and from some retailers seems (like my Bencher paddle) that the price have actually increased.

Is amateur radio immune to economic downturns? Sure seems like the manufacturers and retailers think they are.

Looking forward...

With 2008 officially behind us I've spent the last few weeks (as I'm sure many did) contemplating where we've been and where we're going. There seems to be a pervasive sense of relief, some trepidation about what 2009 might bring, but also a growing sense of hope that we're leaving behind a lot of baggage and moving into a period of revitalization and renewal. I believe that it's human nature to think that the troubles of today are unusual, unprecedented, and thus we long for days of old when "life was simpler". The reality is that in each generation there occurs a crisis of some sort that must be addressed. As the saying goes, "This too shall pass". Fortune, bad or good, is a fleeting thing. Our forefathers struggled, we struggle, and I guarantee our children will struggle. In between these struggles are periods of great happiness, and periods relative calm which often pass by almost unnoticed. From an amateur radio perspective I think 2008 will be remembered as a period of struggle, and hopefully in hindsight will be seen as a time when things began to change.

Amateur radio struggled during 2008. We ended the year with the lowest number of sunspots since the early 1900's. The sun's been so quiet for so long that any time the sunspot number isn't zero, or the solar flux index climbs over 70, everyone gets excited. The quiet surface of our sun was echoed in many ways throughout amateur radio. At the 2008 Dayton Hamvention (and smaller events such as Pacificon 2008) equipment manufacturers offered almost nothing new. In some cases popular equipment such as the Kenwood TH-D7A APRS handheld was suddenly discontinued. (It's speculated that certain parts in the TH-D7A were not ROHS-compliant and Kenwood couldn't get drop-in replacements.) It's worth noting that two of the biggest product offerings of 2008 were the Icom's IC-7200 HF transceiver, and Yaesu's VX-8R quad-band APRS handheld. The IC-7200 has "new" features such as (drum roll please) a USB port for audio I/O and control! How innovative! (I'm being sarcastic.) The VX-8R was shown at Dayton in early 2008 but wasn't actually shipped to customers until mid-December. It contains cutting-edge features such as APRS - which works if you buy their "GPS-Mic" which is insanely large and quite expensive. How is it that my Blackberry Curve can feature a high-contrast LCD display, QWERTY keyboard, battery, multi-band voice/data radio and a GPS in a housing that fits in my hand, but Yaesu needs that much room just to house a microphone and GPS? To add insult to injury; I had an on-the-air QSO with KI6CRL once he finally received his VX-8R after several months on a waiting list -- and it turns out it's got a thermal problem where his transmit audio level drops to nothing as the radio gets hot. This is the hot (no pun intended) new product people waited almost a year to buy?

Perhaps the Japanese manufacturers simply observe that amateur radio is struggling to grab the attention of younger people and believe that it's therefore not capable of producing a good return on investment. I would say that this is both a correct and incorrect observation. It's correct that in its current state amateur radio is largely unattractive to younger people. It's incorrect in that it doesn't take into account the concept of "making a market"; more on this later.

Why are young people not getting into amateur radio? It's not because it's technically challenging; you need only look at the surging popularity of the Maker Movement to know that technical innovation is alive and well among the younger generation. The fact of the matter is that it's our own Luddite mindset that's at fault: It's hard to recruit younger people into a hobby where the equipment manufacturers have only just this year discovered that USB is a viable interface option! I once watched a guy at Ham Radio Outlet whine for five minutes about how hard it was to get RAM modules for his 486 laptop; and amazingly he was finding a sympathetic audience. (By the way this happened in 2006, not 1996.) I was once chastized in an online discussion group for promoting the proliferation of APRS iGates; devices that route packet radio traffic onto the Internet -- my detractor stated that he felt "anything which blurred the lines between ham radio and the Internet" was a bad idea. Finding ways to revitalize older technology with the most pervasive technical revolution since the telephone is a bad idea? Give (unto) me a break.

Even when amateurs use computing they often miss the point. Many people who use APRS are still using the DOS version. One of the most popular APRS applications is UI-View32; the author of which (G4IDE) has been dead for several years -- and specifically asked that upon his death the source-code be destroyed rather than be placed into the public domain as an Open-Source project. How about despite the fact that it's marketed as a stand-alone APRS/packet solution Kenwood continues to build its TM-D710A without a USB or even a PS/2 keyboard jack. Simply put: Amateur Radio can't reach a younger audience until it integrates modern technologies and embraces development/collaboration concepts such as Open Source that younger people associate with "good technology".

You might be saying, "So what? Who cares if we fail to attract and retain younger people into amateur radio?" The answer is simply; we stand to lose everything. The current mood in Washington DC is already somewhat negative towards the FCC; there have even been calls for Obama to dismantle the FCC and implement a new innovation-centric technology governance model. Amateur radio is nothing without our spectrum allocations, and given how we're not really using the spectrum we have it's likely that under the new FCC leadership we'll lose some spectrum in the coming years; someone's going to have to pay back that $700 billion bailout and spectrum leases can be auctioned off to raise cash. As time progresses the incoming FCC leadership is going to be increasingly younger, and likely resistant to the idea of leaving large swaths of potentially cash-generating spectrum in the hands of older amateurs who insist on using out-dated computing technology that increasingly doesn't integrate with modern systems.

So how can we solve this problem? How can amateurs help "make a market" and create a potential for vendors to recoup long-term return on their engineering investment? First and foremost we have got to actively embrace modern computing technology, Maker-style hardware re-purposing concepts, and an Open Source licensing model for software and firmware. This means that:

• All amateur radios going forward should have USB ports, and if appropriate should support USB host-mode.
  
• I should be able to plug my HF transceiver or my handheld into my laptop and control it or configure it over USB.
  
• I should be able to plug a keyboard into my TNC-capable rig and type text without a computer.
  
• Rather than a proprietary interface, and a proprietary configuration app, all amateur radios should contain an on-board web browser (just like a $30 Linksys router does) running from an embedded controller and an Ethernet jack. I should be able to connect the radio to my LAN, and ideally I should be able to plug in a USB Wi-Fi dongle and attach to the radio wirelessly.
  
• The embedded controller should be some kind of standard (ARM-core, etc) and the operating system firmware should be Open Source and modifiable; picture OpenWRT or some variant.

We must start doing this now, or by the time we realize our mistake it will be too late. I firmly believe that a radical departure from our current mindset is the only way to move amateur radio forward.

Where's David?

Been a while since I posted. Most of the summer was spent doing various projects; some for pay and some for fun. One of my new interests is APRS - Automated Packet Reporting System. It started when a ham friend of mine decided to hike the John Muir Trail and wanted me to keep in touch with him and his girlfriend as they hiked. He carried a Kenwood TH-D7A(G) APRS handheld; so I decided that I would set up APRS to track him.

In the process of doing this I learned a lot about APRS and the mechanics of routing packets through RF. I set up an "I-Gate" which is a system that passes received RF packets into the APRS servers via the Internet. Turns out this was quite useful to some local hams that carried Kenwood TH-D7A(G) APRS handhelds which could not normally reach the mountain-top APRS repeaters aka "digipeaters". So now my station's running 24/7; not great for keeping the electric bill small but I guess that's why I have a 3 KW solar PV array on my roof, yeah?

In exploring APRS I learned that when it comes to digipeaters "more" is not necessarily equated to "better". RF packet is about passing packets to the target (or targets) with little (or ideally no) redundancy. For the most part we enjoy a great VHF environment here in the Bay Area; the Silicon Valley is ringed by mountain ranges which provide line-of-sight at nearly any time to at least one of the wide-area digipeaters. Any additional digipeaters are redundant and therefore create extra packet traffic. (The exception to this is of course low-level/low-power "fill-in digipeaters" designed to serve small pocket valleys, urban canyons, etc.) With a dense population and a lot of hams using APRS it's a constant battle to keep the 144.390 MHz APRS channel from becoming too crowded. I-Gates don't contribute to the crowding problem; that is if they're set up as receive-only I-Gates.

I'm having a good time with APRS; besides just being able to track locations I've also been exploring how it can be used for text communication; I had a nice QSO with YB2TJV in Indonesia recently. It's also proving useful to study VHF propogation in the area. I have no idea why my callsign was used by OH7LZB as an example in his blog post on the new I-Gate coverage function on aprs.fi; but I was flattered anyway!

I'll be hosting a forum on APRS at Pacificon 2008 which runs from October 17th - 19th in San Bruno, CA. My forum is scheduled for 8:00am Sunday the 19th; if you're in town please do come by and say hi!

Wireless at Maker Faire 2008

Last weekend my wife went on a short trip with some friends, leaving me home to try my hand at single fatherhood. Still, I managed to get away from my "Mr. Mom Weekend" for a few hours on Friday and Saturday nights (paid a babysitter on Friday, and cajoled my mother-in-law into service on Saturday). On Friday I attended the PAARA amateur radio club meeting in Menlo Park, and on Saturday I drove up to the Maker Faire in San Mateo. The role of wireless technology at the Maker Faire was very evident, but not in the way you might expect. For the uninitiated; the Maker Faire is a combination of Burning Man + science fair + flea market. People come to show off their contraptions and creations; robots, alternative fuel vehicles, lots of stuff which uses embedded controllers, and (especially after the sun went down on Saturday) enough fire and explosions to satisfy even the most ardent pyromaniac. The highlights for me were:

• A carriage being pullled by a walking-robot made up to look like Arnold Schwarzenegger (lower-half exposed to show Terminator endo-skeleton)


• A chamber which made hydrogen-filled soap bubbles that were detonated by electric ignitors


• A seriously huge Tesla coil display which was throwing nine-foot plasma streamers


• Some kind of pressure-sensitive podium which caused twelve-foot tongues of flame to shoot up into the air


• The "Pinbowl" - a perpetual pinball machine

The contrasts at the Maker Faire are numerous and glaring. The parking lot is filled with hybrid cars, and the usual "Impeach Bush"/"Obama 2008" bumper-sticker polemic you expect to find in the SF Bay Area. So you'd think the Maker Faire would be focused heavily on eco-friendly and minimal carbon footprint exhibits. And yes, there were a huge number of exhibits showing off renewable energy and transportation technology; solar, wind, algae-fuel, bio-diesel, electric motorcycles, pluggable hybrids, etc. But after sunset there were also many combustion exhibits and shows using propane, kerosene, lamp oil, etc. The smell of incompletely burned hydrocarbon was everywhere, as tongues of smoke curled up against the deepening sunset in the chilly evening air. How to reconcile this? I don't know that I can. Is the Maker Faire a neutral zone in the global warming debate, a sort of United Nations of carbon consumption? Or is this yet another example of hippie hypocrisy? Best if we leave that one to the philosophers.

If you're still reading, you might be wondering how this all relates to wireless. It does, and thanks for sticking with me as I get around to that. Wireless technology of all types was very evident and widely used at the Maker Faire, but the operating word here is "used". There were no exhibits (that I saw) which showed off anything related to innovation in the wireless space. There were a ton of people using Wi-Fi, Bluetooth, proprietary ISM data-link radios, radio-controlled servos, etc. Wireless was everywhere, but in all cases it was "user wireless"; projects created with off-the-shelf modules and in some cases chipsets. Wireless is a tool to complete projects, not the project in and of itself. I find that this echoes a growing trend I've observed at the WCA and in the wireless industry as a whole: Put plainly, wireless technology is becoming a commodity.

Some of the hams from PAARA set up an amateur radio special-event station to make 20m and 2m/70cm contacts from the Maker Faire. I never found this exhibit, but a few people on the N6NFI repeater say the station had to contend with some bad RFI; which I can imagine given that a giant Tesla generator was operating nearby. I'm quite sure that most of the Maker Faire was essentially a gigantic FCC Part 15 violation.

It's unfortunate that the hams did not have a bigger role at Maker, because amateur radio has its roots in innovation and home-brewed technology; ham radio is a great-great-granduncle of the Maker movement and should rightfully hold a place of honor and respect in the Maker community. I think that the problem is that a lot of amateur radio has become consumerized and is now ironically an example of the "culture of learned helplessness"; ironic because the technology consumerism which is the fastest growing segment of amateur radio (i.e. people who chose to buy versus make) is at odds with the hacking/creation/innovation core elements of the Maker movement.

The amateur radio community still certainly has a lot to say about innovation and technology; the huge number of hamfests, tech days, field days, DXpeditions, etc is evidence of this. The problem seems to be that amateur radio events have become somewhat insular; we're doing events for ourselves, and not reaching out as much as we should to non-hams. By way of example; this month's AM-TECH Day is on May 10th. Past proof shows that it will be popular, or at least popular with hams. Wouldn't it have been better to push AM-TECH up a week and hold it at the Maker Faire? How many Makers could we have licensed if we'd held AM-TECH and a VE test session a week earlier at the Maker Faire?

I also think that we need to seriously rethink our approach to new technologies. Hams are spending way too much energy on "maintaining the tradition" in modes of operation such as CW and voice, and not exploring how amateur radio might benefit from integration with other technology. I think radio amateurs still have a lot to offer the wider technical community, but we need to reach out and open our doors. This means far less worrying about nurturing traditions and whining about the evils of no-code HF, and a lot more mold-breaking. The concept of the Maker Faire and amateur radio is to hack, to repurpose, to change forms and function. We can learn a lot from the Maker community, and they from us. How do we make this happen?

The Sound of Silence

Last November we drove down to Disneyland in my wife's van, and I wired up a VHF/UHF rig and mag mount for the trip. Ever since the phone systems failed due to overloading during the relatively minor October 2007 Alum Rock quake I've been nervous about relying on cellphones in emergencies. I spent some time researching repeaters along the route, and more time programming everything into the radio.

All for naught, apparently. During the trip I was struck by the almost complete lack of traffic on every repeater I tuned in. It wasn't a problem with my equipment; there just wasn't anyone on the air. Even in the densely populated Los Angeles area, the entire twelve hour trip was mostly a never-ending chain of silence. The most traffic I heard was on linked systems such as the Cactus Intertie and the WinSystem, but that's to be expected because they have dozens of connected repeaters and all it takes is one person talking somewhere on the system to light them all up.

On my base and mobile rigs I have a lot of local repeaters programmed, ready to go. And yet at any given time; nobody's talking. Pick up the mic, announce "W6DTW monitoring".... and listen to silence. Reminds me of the This Week In Amateur Radio "Random Access Thought" segment by Bill N2FNH about a repeater that died when a spider crawled across a circuit board; shorted himself across a resistor; killed the repeater...and nobody noticed. And yet; try asking your local frequency coordination council for a frequency pair and you'll get told "there's nothing available". The howling wind of silent FM static is blowing through most of our local repeaters just as it was through the repeaters I tuned into on the trip to Southern California. So how is it that all of the frequencies are spoken for..?

Things are not much better down in the HF bands, or perhaps I should say not much better in the legal HF bands. Given that we're currently coming out of a low point in the 11-year sunspot cycle you might be tempted to allow that the amount of traffic will be low. Especially in the higher frequency bands like 10 meters, where popular wisdom says there's little propagation during the day and certainly none at night. So the 40 and 20 meters bands have some traffic (mostly contesting), 17 meters opens up around noon for a while, and we're starting to hear folks on 15 meters. But for the most part; few stations are on the air and silence above 21.5 MHz is the rule.

So then why is it that on any given weekend day, if you listen above 27.405 MHz into what's been termed the Freeband, you'll very likely hear a lot of traffic? I hear strong stations coming in from around the Western US and Mexico. Is there something odd about propagation that creates a difference between 27.915 MHz (aka the freeband "Redneck Skip Calling Frequency") and 28.400 MHz (aka the amateur "10 Meter Calling Frequency") so that one is active and the other not? Surely the Freebanders don't have some kind of secret technical prowess that allows them to punch through where amateurs cannot? The reality is likely that amateurs simply don't believe that there's good propagation without sunspots, so they don't tune in and "no propagation" becomes a self-fulfilling prophecy.

I find it amazing that while the great swaths of spectrum which amateurs can legally use sit idle; another group of people who are sometimes called "pirates" (agree or disagree with the term as you wish) are happily making use of frequencies which are right next to a band that amateurs will effectively ignore for a good 25%-40% of every sunspot cycle. Yes, Freebanders are operating illegally according to FCC regulations. No, I'm not a Freebander. However; I do have a sense of respect for them. They are (from what I can see) more enthusiastic and aggressive about pursuing the hands-on technical aspects of radio than many hams. They're out there modifying radio equipment on their own---which they have to do because there's no legal way to buy freeband radios. They're not sitting around waiting for sunspots to come back so they can get good propagation; they get on the air and take what the sun gives them on that day.

That's real radio.

Expensive Desktop Mic Get Pwned By $12 VOIP Headset

A while back I purchased an entire amateur radio set from a ham who was getting out of the hobby. A rare occurrence, mind you. I really only wanted the radio (a Yaesu FT-1000D) but the guy sold me everything except the feedlines and antennas for less than I'd expected to pay for the radio. Everything worked as expected. In the plethora of boxes I lugged home were a lot of accessories; among them a West Mountain Radio RigBlaster Pro.

The RigBlaster sat in storage for almost a year, until recently when I watched K7AGE on YouTube talking about his homebrew Bluetooth headset interface. One of the accessories which came with the FT-1000D was a Yaesu MD-100A8X desk mic. I've frankly been less than pleased with performance of that mic; it's very sensitive to any change in sound level due to distance from my mouth which means that keeping the FT-1000D's ALC from kicking requires that I constantly ride the PA drive control--and that's tough to do when I'm focused on maintaining a constant mouth-to-mic distance. So I started thinking about getting a headset. Of course, you can spend a ton of money on a "good" headset; e.g. Heil Sound is the name in radio mics and headgear and their stuff starts over $100 and goes up from there. Being the cheapskate I am I decided to experiment with a $12 General Electric VOIP headset I got from Target to do Skype while I was traveling through Asia in 2006.

Interface to Yaesu was a snap using the RigBlaster. As with most amateur radio accessory companies, West Mountain Radio's website and manuals are poorly written but I was able to decipher them enough to set the jumpers properly for the Yaesu. Most computer headsets are have electret voice elements which require a 5 VDC bias on the ring terminal; the RigBlaster can provide bias on the MIC2 jack which also happens to be the perfect size for a PC headset plug. I didn't bother to route any of the receive audio paths; for now I just have the receive side plugged into the headphone jack. I have the MD-100 plugged into the RigBlaster--just in case--but its primary function now is to act as a PTT switch.

The results were impressive. I checked in to the 75M late night net and got an unsolicited report of "great sounding audio" from W6EZV. A flattering report, considering that the 75M late night guys are used to hearing perfectly processed and equalized audio from people like W6OBB aka Art Bell. I'm now able to operate with both hands free, and the headphone has an added benefit of making sure the receive audio is not bothering my family after they've gone to bed. My audio settings are a lot more consistent and don't require constant fussing with the PA drive and speech processor levels. Best of all I'm no longer inclined to go out and spent hundreds of dollars to get a high-end Heil headset. I'm now curious to find out if my successful experiment is unique to this particular VOIP headset or if I can get the same results with other brands.

New Antenna!!

My wife spent the day visiting a friend, and took the girls with her, which left me about 12 blissful hours on a weekend to do whatever I wanted to do. I'd be intending to install a new HF antenna for some time, so this was the best and obvious time to do this.

I put out a call asking my amateur radio friends to come by and help. Bojan agreed, which was great. He's a bright guy, very creative when it comes to technology. If you're ever looking for someone who can turn ideas into reality, give him a call.

The antenna I chose was a Comet CHA250B. This particular antenna is unique in that despite being vertically-polarized it has no ground radials, and it will also tune all bands from 80m to 6m. The coax feeds into a large black cylinder which acts as a matching network. This particular antenna has been alternately praised and vilified on review sites like eHam. People are either giving it a 0/5 or a 5/5. There doesn't seem to be a lot of rhyme or reason to this; although it's interesting to note that people giving it a 0/5 tend to compare it to a dipole which might be unfair.

For me, I was willing to try it out. Considering that my comparison point was my aforementioned $2 "Speaker-wire Special" I suppose anything would seem better. The real challenge in the antenna install was not so much the outside work, it was deciding how to get the coax up to the roof from my shack. Doing so entailed slithering around in my attic, which is a complete mess after a roof replacement earlier this year. There were also a few setbacks, such as a broken lag bolt and a too-small bracket on another antenna (my HDTV antenna) which is now needs to be adapted to the new larger mast.

In the end we got the Comet installed, and two extra runs of coax. I fudged up a temporary VHF/UHF antenna (until I can get a replacement lag bolt and the new mast installed) by slapping a magnetic mount down onto a metal attic vent. I may also sell the VHF/UHF antenna I had on Craigslist and get something else because it's a 6m/2m/75cm tribander and the Comet now covers 6m.

As expected the Comet performs better than the homebrew. I'm getting signals where there were no signals before, I don't have RF-in-the-shack problems like I did before, and the antenna is clearly quieter (lower noise floor) than the homebrew. It tunes a lot of bands, so all in all I'm happy with it. I'm not quiet sure why some people have panned it so hard on eHam. I suspect that it may have to do with unfair comparisons to dipoles, but also it might be the install makes a difference. The Comet's instructions call for it to be installed 32 feet off the ground. Perhaps if it's not installed at that height the matching network doesn't work?

JT65A-HF, we hardly knew ye...

A while back I wrote about JT65A, the amateur radio weak signal digital mode being used on HF bands. My best contact was just before Field Day 2007 when I logged ZS6WN in South Africa; over 10,500 miles using 50 watts and an antenna made of speaker wire at the bottom of the sunspot cycle. It was a very interesting and powerful mode. And yet I haven't heard anyone on the bands in over a month. Which leaves me to ponder; why?

WSJT (the software for JT65A) was originally written for weak signal paths such as Earth-Moon-Earth. As with most weak signal modes, a trade-off is made where the amount of information transmitted is intentionally limited in order to pull weak signals up out of the noise floor. In JT65A, the total transmission cycle was one minute (actually, about 48 seconds plus 12 seconds for the recipient to react and respond) and in this minute only 13 ASCII characters could be sent. Not exactly a rag-chewing mode. So once I'd worked a station and logged them, I was basically done. I'd see someone calling CQ, note that I'd already logged them, and so wouldn't respond. And once I'd worked ZS6WN in South Africa, working non-DX contacts was (to be blunt) boring.

So my theory on the premature demise of JT65A on HF is this; everyone worked everyone and once they were done there was no point in continuing. Radio amateurs like to rag-chew, talk about stuff, brag about their rigs and such. Hard to do at 13 characters per minute. And without a conversation, it's hard to make friends. Sure, you could always get to know folks by hanging out in the Ping Jockey web chat, and there's certainly a core group of people who do just that, but if you're going to chat in a chat room then why bother with a radio? So I think JT65A on HF has turned into the one-hit-wonder of amateur radio.

Echolink Follies

One of the developments we're seeing in amateur radio over recent years is the proliferation of VOIP and digital voice technologies. Examples of this are things like D-Star, IRLP, and EchoLink. The latter is sometimes a contentious technology, in that some amateurs don't consider it "real" radio because the audio/control interface is PC-based. Once while on a visit to San Diego I was having a pleasant conversation with a local repeater operator which turned very sour at the mere mention of the word "EchoLink" as he went into a tirade about the evils of the system. Normally hams reserve this sort of loathing for CB radio and BPL companies, so I was a bit surprised.

Since then I've encountered a few more instances of "EchoLink Enmity". My personal opinion is that there's little difference between controlling a radio/repeater with EchoLink versus using Ham Radio Deluxe plus Skype to control a rig remotely. The question of whether EchoLink users are higher or lower on the amateur food-chain is best left to the philosophers. I will concede however that there's an annoying element to EchoLink, but it's the fault of the developers and not so much the users themselves.

Allow me to explain: Most if not all EchoLink users are unaware that when they connect to a repeater or simplex link the server software by default transmits an announcement over the air which says "Connecting to EchoLink [callsign] -- Connected". Since a lot of EchoLink users are looking for QSOs (amateur-speak for conversations) they tend to hop from repeater to repeater looking for traffic. If a repeater's quiet, they tend to silently disconnect and go looking elsewhere. And again the server software by default transmits an announcement which says "[callsign] -- Disconnected". To the locals on the repeater, this can seem a bit rude. If the EchoLink user was looking for a QSO, then why didn't he transmit and ask if anyone was interested/available to chat? So throughout the day you hear a lot of Connect-Disconnect, Connect-Disconnect...over and over again. After a while, you might start to think that maybe EchoLink users really are bozos.

However I think the users are largely not to blame for this. The connection announcements are not played back to the EchoLink client's inbound audio, so users don't know about them unless they're listening to the repeater in question. Most EchoLink users connect to remote repeaters or links in other parts of the country or even around the world, so they often don't ever hear what goes out over the radio. I once sent a detailed email to the EchoLink developer team explaining all this. I was told that a repeater/link admin can turn off the announcements, but they're on by default. Most admins clearly don't bother to turn announcements off, and the users are unaware of them. I suggested to the EchoLink developers that they might want to add a note to the EchoLink FAQ/guide explaining all this, but they didn't. And so EchoLink users will continue to unwittingly annoy repeater users, and apparently the developers think this is OK. I don't understand this, but whatever. Therefore, here are my How Not To Be An EchoLink Bozo tips:

• Be aware that every time you connect/disconnect, your callsign is transmitted over the air.
• Knowing the preceding it should be no surprise why when I further suggest: Don't repeatedly connect/disconnect to the same repeater. It is amazingly annoying to the locals when you do.
• Try saying hello if it's quiet. You may be surprised at how many locals are listening and willing to come back and chat with you.
• Be careful about "calling CQ" on a repeater. CQ is traditionally used for simplex contacts, and a repeater is not a simplex system. Some people won't care, but others will think that you're a bozo. If the EchoLink node ends in "-R" it's a repeater and I advise against calling CQ. If the node ends in "-L" (a link node) then CQ is probably OK.
• Don't ask for a QSL card because you made a contact over EchoLink. People will think you're a bozo. For that matter; I will think you're a bozo. QSL cards are for commemorating simplex contacts. Would you send a QSL card to someone you chatted with over Skype?

How not to build a transceiver

Primarily due to its flexibility, one of the most popular mobile rigs for amateur radio is the Kenwood TM-742A and associated models such as the 942, 741, etc. The TM-742A is a tri-band rig which can accept up to three band modules out of an available five; 10m, 6m, 2m, 1.25m, and 70cm. Interesting trivia; the MSRP in 1994 was $660. Today, clean TM-742A rigs can and do go for over $750 and rising as replacement parts and band modules become harder to find.

Every rig has its quirks, and a quirk of the TM-742A is that the 2m module is prone to failure. The 2m power amplifier is a Toshiba S-AV17 which is a set of power transistors and associated components soldered onto a beryllium ceramic substrate. Symptom of the failure is that the rig will transmit enough power to be heard on other close-by (within a few tens of feet) rigs but makes no power at the antenna. Most people just pony up the $65 and replace the S-AV17. Others have discovered that the failure lies in a microscopic crack in the ceramic that breaks one of the microstrip filter traces. The fix for this is to remove the S-AV17, pry off the plastic cover, and run a rapid thermal recovery soldering iron (like a Metcal or Hakko) over the crack area. A standard resistive heater iron will not work; because the ceramic module is designed to absorb lots of heat so the trace won't get hot enough to flow. It takes 15 minutes to disassemble the rig and 15 seconds to solder it. Thanks to Kevin W3KKC for his webpage discussing the problem and walking through the repair process; complete with photos.

(Disclaimer: beryllium is nasty stuff. You don't want to inhale it. If you're not comfortable doing this; don't have the right equipment; etc blah insert dire warnings here then pay the $65 and don't try to repair the amplifier!)

Interestingly enough, and relevant to the title of this post, is to examine why the module fails. The reason for the failure is excess heat. The stock configuration for the band modules is to have the 2m in the middle, which means that the 2m power amplifier is buried about as deep in the rig as it can be. At 50W the 2m module is also capable of the highest power output, so therefore it gets hotter than the other modules. The ceramic cracks and you get a dead S-AV17. I would accept this explanation readily enough except that every 2m module I've disassembled has had the same problem; the S-AV17 is mounted dry. Not one has used any form of thermal grease to promote conductivity into the heatsink and transceiver structural frame. This would be like a high-speed CPU being installed onto a motherboard without thermal grease; the CPU is essentially guaranteed to fail from thermal overload. This is (or more accurately was) a blatantly stupid move on Kenwood's part that has cost radio amateurs thousands (if not tens of thousands) of dollars in unnecessary repairs, replacements parts, shipping costs and downtime. Can you demand a recall of a 14 year old product?

Amateur Radio: 5,200 miles on 50 watts and a $2 antenna

Lately I have been getting prepared for the annual ARRL Field Day, which is an annual operating exercise and public showcase event for the amateur radio world. Amateurs all over North America will set up in campgrounds, parking lots, and fields and attempt to make as many contacts as possible using various "modes"; everything from Morse Code and "phone" (what normal people would call voice, talking into a microphone) to exotic digital setups which use computers connected to radios. My club (the Northern California Cactus Radio Association) will operate as K6SRA from a campground in Henry Coe State Park, near Morgan Hill CA.

I'll be running the digital station this year, and plan to use (in addition to the usual PSK31 and RTTY setup) a very new mode called JT65A-HF. JT65A isn't new to amateur radio as it's been used for a while for "moon bounce"; and yes, I mean literally for bouncing signals off the moon. Earlier in 2006, a few people decided to transmit JT65A signals over the HF bands; primarily 20 meters (14.076 MHz) and 40 meters (7.076 MHz). In only a few months this new mode has exploded in popularity, primarily due to the very high sensitivity afforded by a Reed-Solomon forward error-correction algorithm implemented this mode. It's mathematically provable that JT65A signals can be detected with 100% certainty even if the received signal is -22 dB under the noise floor.

In preparing for working JT65A-HF on Field Day I've been learning to use an application called WSJT which is used mostly by the moon bounce and meteor-scatter folks but now also HF enthusiasts. I've made some amazing contacts this way; just tonight I logged a contact with a guy in Australia using only 50 watts of power and a homemade antenna I built with $2 worth of parts I had lying around my garage. This is the equivalent of someone being able to see a 50 watt light bulb from space at a distance four times that of the International Space Station, or of someone talking from San Jose CA to San Diego CA on a CB radio. I expect we'll be seeing a lot more of JT65A in the HF bands, especially as radio amateurs suffer through the poor radio propogation conditions created by the current solar minima.

Update (15 June 2007) : I just beat my Australia record with a solid contact to ZS6WN in South Africa. 10,526 miles, same power, same antenna!

Update (24 Sept 2007) : WA3LTB has created a video demo of WSJT and posted it to YouTube.