Taming excess data usage by Chromecast

Chromecast uses a lot of data, even while idle.  This tip can help reduce that usage.

This has been a known issue for some years, going back to at least 2014.  The problem is the Ambient Mode in Chromecast, which displays artwork and images when nothing is being streamed to the Chromecast.  And to be sure, the images it displays are attractive and fun to look at.  But because they're so high-resolution, the data consumed by Ambient Mode is noticeable. 

The problem is exacerbated by the increase in data usage from newer smart home devices like doorbell cameras and security cameras, which tend to upload large amounts of data to the cloud for AI features like facial recognition.  Combined with the high data usage of Chromecast Ambient Mode, this puts you at risk of exceeding the data caps from your ISP - and getting an unexpectedly large bill.

In the past, tips such as plugging the Chromecast's USB power cord into the display's USB ports (so that it's unpowered when the display is off) are helpful, but that still means the Chromecast is using data any time you're using the display for any reason.  During a long weekend of DVD watching the Chromecast will still consume data as it downloads high-res photos.  A couple of years ago, someone had the idea to post two small 16 x 9 pixel images of a solid color in Google Photos, and then set the Chromecast to display only that image folder, but for some reason that's no longer working.  Another tip is to set the Chromecast to cycle images only every 10 minutes, which helps but not very much. 

Chromecast now has an Experimental Mode for Ambient, which now includes a Low-Bandwidth setting.  But if you're operating on a very limited data plan, even this may be too much.  So what to do?

My tip is to block Chromecast from getting data at all.  Use your Wi-Fi router's client management feature to block the Chromecast when you're not using it.  I use the Google Wi-Fi mesh system, which allows me to create an On/Off blocking switch for any Wi-Fi client device.  Most modern Wi-Fi routers have a client management feature.  When I want to use my Chromecast, I unblock it.  When it's blocked, it can't access the network - so it can't download anything, and you run less risk of exceeding your data cap. 

Mobilinkd interface with TM-942A / Shack

A while back I bought the excellent Mobilinkd TNC - a device that interfaces amateur radio with smartphones and PCs via Bluetooth.  There are a ton of useful applications for this, not the least of which is being able to place my radio where I want it, and not be cable-tethered to it.  I've used the Mobilinkd TNC with a Kenwood TH-F6A as a mobile device, and that worked very well - I can leave my radio and the TNC in my backpack and type messages on my smartphone.  If I'm doing something mobile/portable like parade/race support, I put the radio/TNC and a battery pack up where it can get good reception and use my smartphone or PC as the interface - as long as I'm in Bluetooth range, I'm good. 

I've long been a fan of the old Kenwood TM-742A and TM-942A tri-band mobile radios.  I own several of them, and have become fairly well-versed in the art and science of repairing them.  I've always been curious about a somewhat unique feature of the radio, which is the Receive Data (RD) line on the microphone 8P8C connector - it's a direct feed of the receiver audio intended for packet radio that bypasses the final audio shaping/amplification stage, with a 100 mV pk-pk signal across a 10k load. 

I run a TM-942A (which is just a TM-742A with the 1.2 GHz band module in third slot) in my shack, which is interfaced to an MFJ-1263 microphone switch.  I thought it would be interesting to wire the Mobilinkd into the MFJ-1263 switch, so I could use the TM-942A for audio or APRS/packet at the flick of a switch.  The RD line makes this really simple to wire up.  Critical for APRS/packet applications, the RD line is tapped off before the squelch and CTCSS circuits - so I can monitor the audio for debug, or mute it as needed, without having to worry if the squelch and CTCSS settings are screwing with the RD line.  (Of course, this requires me to run DCD on the TNC software, otherwise it will never transmit while it sees the channel as "busy".)  Volume control also has no effect. 

I started off by ensuring that the MFJ-1263 was jumpered properly to bring the TM-942A connector out to the switch's front panel 8P8C jack without re-ordering the pins.  I put this onto the switch's A-side, and left my voice microphone on the B-side.  I had previously built a 3.5mm (1/8th inch) TRRS cable with breadboard pins soldered to the ends for my test kit.  I also have an 8P8C breakout board in my test kit.  Both pieces were jumpered together on a small breadboard.  Once I had the wiring confirmed, I made the cable permanent.  It might sound like overkill to proceed this way, but the TM-942A's microphone jack also has an 8 VDC (@ 100 mA) voltage source, and I wanted to make sure I wasn't injecting a voltage into my TNC. 

I'm really happy with this set up - I can use the Mobilinkd TNC at home, or take it mobile by simply unplugging the TRRS connector and USB power cable.  My Mobilinkd stays charged via USB when it's in the home configuration.  My only gripe is that the Receive Data line from the TM-742A is a fixed level which is slightly lower than the Mobilinkd's software wants to see, but it doesn't appear to be affecting decode on APRS. 

Easy Project: Cellphone/Tablet Charging Stand

With the new school year came cellphones for the girls. We wanted to make sure that they didn't store them in their bedrooms - we have enough trouble with getting them to sleep and don't want to add to the problem, and we want to make sure they're charged for the coming school day.  So Tara and I built a cellphone/tablet charging stand.

Parts were simple and inexpensive.  We already had a small free-standing shelf obtained from a garage sale, similar to the Furinno 5-tier corner shelf (Amazon, $27).  Similar items can be found at Home Depot and Wayfair for under $40.

I ordered an Anker PowerPort 60 watt 6-port USB charger (Amazon, $28) and two sets of 4 ft cables - one for Android (Micro USB - Amazon, $11) and one for iOS (Lightning connector - Amazon, $22).  Don't get me started on why iOS cables are 2x the cost.  (Hint: Apple is evil.)

To show how easy this project is, I tasked my 10 year-old with the build.  She felt it necessary to wear a sequined cocktail dress for the photos.  I stopped questioning these things a while ago.

With all parts removed from their boxes she prepped the adhesive which would attach the Anker PowerPort to the shelf.  I'm partial to 3M Dual Lock because it's very sticky yet removes with no residue, and it allows the pieces to be separated if needed.  Unfortunately, it's also crazy expensive unless you buy it in bulk, in which case it's only kinda expensive (Amazon, $3/ft).  I found that the 3M Command Adhesive strips didn't work, as the Anker PowerPort has a fingerprint-resistant coating to which the Command Adhesive won't adhere.  Double-sided sticky tape might work, not sure.  A bit of surface prep on the surfaces with an alcohol wipe helped.

Assembly is simple.  Attach the Anker PowerPort to the back side of the shelf.  Insert USB cables.  Plug into wall socket.  Charge devices.

Thoughts on the build:

• I bought 4 ft cables.  I probably could have got away with 1 ft cables.  Coiled cables might be better.  
• I'm going to add some kind of cable organizer to keep cables tidy when not used.

Review: August Doorbell Camera

El Doorbell Del Diablo

Update: After replacing the August Doorbell with a Skybell HD, and having just as many problems with the Skybell, we switched to Nest Doorbell Cam and have had no problems.  The only thing worse than security that doesn't work, is security that sometimes works - because you can't trust it.  Spend the extra money and buy quality security equipment.  Trust me on this...

Last year a friend bought two "smart" doorbells for his home, and decided to keep the one he installed first.  So for a discount, I was able to pick up an August Doorbell Camera.  What followed was a journey lasting several months, ultimately resulting in me buying a different product.

I loved the idea of smart doorbell.  Living in a city which due to budget issues and a pension crisis has only 2/3rds of the police officers it needs, and with my wife such a fan of online stores for everything, we're careful about quickly pulling in mail and packages.  Research has shown that burglars will almost always ring the doorbell before attempting a robbery, so if you can appear to be home - they'll move on.  That, and our very large dog, seemed like a good strategy.

I installed the August Doorbell Camera in August 2016, and immediately began noticing issues with it.  Switches on the smartphone app were not properly synchronized between Android and iOS - in fact in some cases turning a switch ON in Android resulted in the switch being OFF in iOS and vice-versa.  I found that when changing a setting in the app the change wouldn't always register.  The device wanted a -60 dBm Wi-Fi signal - which an RF-savvy person will tell you is really hard to get unless you're practically right on top of the access point.

More than anything else my frustration was with the inconsistency of operation.  August Tech Support (which from what I can tell either isn't located in the US or they keep really odd office hours) would often remotely reboot the device and it would work for a day or so, then begin failing.  What's worse than something that doesn't work?  Something that works intermittently.  I'd get a motion or doorbell ringing alert - and the video file would show "unavailable".  Or I wouldn't get the alert.  Or I'd get the alert but be unable to remotely answer the door.  I never knew what to expect.

I gave up on the August Doorbell Cam on March 31st 2017, over seven months after installation.  During that time I exchanged countless emails with them - easily over 100 total.  To their credit, they tried to help - I received two replacement doorbells, including one after the doorbell just completely gave up and refused to reset or connect to anything.  I never felt I could rely on the device, and in the end I wanted that reliability.

Maker Faire Tips in QST

My article on Bay-Net's efforts to showcase amateur radio at Maker Faire Bay Area is in QST (January 2017 edition) hitting mailboxes and digital readers now.  I blogged about this year's project back in May 2016, and that article contains links to detailed materials and presentations.  We also talked Maker Faire with the HamRadio360 team in their late June podcast.

Special thanks again to my team that worked hard on this event: +Beric Dunn, +Bernard Van Haecke, +Derek Kozel, +Marcel Stieber, +Kenneth Finnegan, +Maria Pikusova, and Bob Somers.

Also in the article is an interview with fellow Maker +Jeri Ellsworth on her journey away from and (finally) back to amateur radio, and a cameo appearance by my youngest daughter Tara.

Holiday Project: LED Flip Light

The original idea for this project came from David Bakker at draailampje.nl ("draailampje" means "flip light" in Dutch) via Make: - I've modified it slightly.  My kids both like to solder, so I wanted a project which my youngest could do mostly by herself.



Parts:

• Batteries: http://amzn.to/2gQYk9P
• Battery holders: http://amzn.to/2enJDbT
• Switches: http://amzn.to/2gWmzpN
• 10mm LEDs: http://amzn.to/2g0AOoY
• 1.5 oz jars: http://amzn.to/2gDZjME

The idea of the flip light is very simple: parts needed are a CR2032 battery, a coin battery holder, a tilt switch, and a 10mm diffused LED.












This assembly is mounted into the lid of a small hexagonal glass jar with hot glue.  We built 20 of them in assembly-line fashion, with me acting as safety observer and occasionally suggesting that she re-solder some joints.

Operation is dumb simple; flip the light over to turn it on, back again to turn it off.

The CR2032 battery drives the LED directly - no current-limiting resistor is needed.  You have to make a choice about orientation - David Bakker's original design is to have the light on when the lid is up.

My daughter decided to have it on when the lid is down, with the LED pointing up when on, so that the light comes out the bottom of the jar.  She felt this was more "pretty".

The end result was really nice - she tossed a few on the mantle, put some on the dining room table, and gave a few away as gifts.

The most expensive parts of the project were the glass jars.  You can get them for about $1 each if you buy a box of 24.  Parts list above.

Update: LED Hack for Christmas Houses

2016 Update: Updated links to parts sources - some had broken since the original post.  Also: For a festive touch, we use color-changing LED tea lights in the Fezziwig building.  That guy knew how to party!

Last weekend my wife and I started getting the Christmas decorations out of storage.  One of my wife's holiday favorites is a set of Dickens-style houses/buildings, some have signs like "Scrooge & Marley" "Fezziwig" etc.  Each has a C7 lamp and a cord.  Given the number of houses she has, cord management is always an issue.  We wind up trying to hide them with fluffy "snow" fabric, and then we have to hide a socket-strip and all the plugs.  The lights get hot, so in proximity to the fabric there's always a fire risk if one of the lights were to pop out.  The houses are fun, but it's a huge mess, so we decided to homebrew some LED lights for them.

Top removed from thread protector

We started by buying a set of small submersible LED tea lights.  These typically come in packs of 10 - 12, are used for weddings and such (toss them in the bottom of the punch bowl, etc), and cost about $0.80 each.  You can get them in white, color-changing, or a mixed set.  Each light uses a couple of CR2032 batteries, so we picked up a pack of 20 for under $8.00. The lights arrived with batteries, and only one of them was depleted, so we were good to go.  We also discovered that a color-changing light had got mixed into our set of white lights, which the kids decided was really cool because that house "looks like they're having a party". 

LED glued into thread protector

As it turns out, some of her houses have larger openings for the C7 lamps, so we just set the light on the table and put the house on top of it.  The others had smaller openings, so I needed to hack something up.  We considered using modeling clay, but I thought that might get messy.  Sugru or InstaMorph (moldable rubber) would have been great, but I used all my Sugru to make a custom mount for a Wii sensor.  Then I remembered that I had a bag of pipe thread protectors left over from an amateur radio antenna install - I use them to make custom grommets for my coax cable ingress box.

Perfect fit!

As it turns out, the LED lights friction-fit perfectly into thread protectors.  So I sliced off the end to expose the LED.  I put a few drops of hot glue on the thread protector to secure the LED.  They fit perfectly into the holes where the C7 lamps used to go, and they put off good light.

We're pleased with the end result, but if I had to make a change I would use amber/yellow LEDs instead of the pure white we have now.  Maybe over time I'll swap in some of those if the white ones fail.  In the meantime, our Dickens Village is lit up with no cords or concerns about fire danger. 

Earthquake Go-Kit - Pirate Radio?

In the wake New Zealand's recent Kaikōura earthquake, locals have been relying on an FM radio station called "Brian FM 100.3" to provide them with news about where to find food, running water, and toilets.  The broadcasters set up a similar radio station in the aftermath of the 2011 Christchurch earthquake.

Radio New Zealand article

In the US, this would probably be unnecessary - most of our broadcast stations have well-engineered towers, backup towers and power sources, and redundant studios.  New Zealand likely has a lot of idle FM spectrum, even when there's not an earthquake, so the Brian FM network can move around as needed to provide coverage and information to hard-hit or remote areas.

Build a (fire)wall and make China pay for it

I've been gradually building up a Raspberry Pi for use in my shack, and I've also been experimenting with a home control and security systems hosted on Pi platforms.  To be really useful, a home control system needs to be accessible from outside my home, and a remote radio setup would also be nice.  This has led me down a path of learning about how to conveniently but safely expose ports on my Pi platforms to the internet.

At any given moment, there are thousands of attackers active on the internet.  If you expose ports like TCP 80 (web server), or TCP 22 (ssh) you will be attacked, likely within minutes.  These attacks range from sophisticated hack attempts carried out by state-sponsored security teams, to teenagers running automated scanners that look for obvious weaknesses like unmodified default passwords.

Most attacks try to leverage brute-force methods - they start with a presumption that the superuser login is "pi" (the default) and work through a list of obvious passwords like the default "raspberry", or "pi", or "password", or "123456", etc.

Presuming you've changed your superuser password (and ideally your login name) an easy method to add security is to implement fail2ban.  The fail2ban method tracks failed login attempts over time, and if the same IP address fails more than X times within Y minutes, that address is then added to a ban list in iptables.  If your password is non-obvious, this works fairly well.  The problem is that, without additional setup, iptables exist in memory and are wiped on every reboot.  And because they exist in memory, you'll ultimately waste Pi resources trying to exclude billions of IP addresses.  It's possible to preemptively ban ranges and subnets of IP addresses, but you're still talking about nearly 8,000 entries just for a single country like China.  Also; fail2ban only works if someone actually attempts a login - it does nothing about attackers who probe connections without logging in.

The reality is, the number of IP addresses from which I want to allow connection is very small, and (unless I'm traveling) they're all US-based.  So the trick is to only allow connection from IP addresses originating in the US.  Turns out this is possible using GeoIP and some scripting.  The GeoIP method uses a file database of IP address ranges listed by country.  When an ssh client connects, their IP address is compared with the database.  If the IP address is not from the US, it refuses the connection.
I still run fail2ban, to handle any US-based attackers, and to deal with any non-ssh traffic.  Let me know in comments if you use GeoIP for security, and what you think of my strategies.

Nexus 6 Review: Wi-Fi Done Right

I've been a Droid user for many years.  Started out with the Droid 1 then onto a Droid 2, Droid RAZR Maxx, Droid Ultra, a very short-lived and painful experience with the Droid Turbo, then a Droid Maxx which is essentially a slightly fatter Ultra with more battery.  When my battery's capacity started to run short, I started looking at other phones.  I decided to get a Nexus 6 (unlocked from Amazon) when Google announced that they would roll out Wi-Fi Assistant to all Nexus phones.

Wi-Fi Assistant was originally a Google Fi feature that applies a VPN to open Wi-Fi access points - without user intervention.  In fact, Wi-Fi Assistant is now (once you have the Play Services 9.6 update) capable of securing all open Wi-Fi, even ones where you manually connect.  This is a huge move by Google that will hit the cellular carriers hard because if I'm able to use public Wi-Fi with confidence, and my phone is latching on to open Wi-Fi by itself - why do I need a large data plan?

This all takes Wi-Fi a step closer to being a viable alternative to cellular data, although there are still many issues.  The problem is that managing a Closed SSID network is painful and complex, and Open SSID networks are subject to abuse.  Wi-Fi also suffers from a handoff problem (i.e. it has no handoff method) and it's fairly easy to do a man-in-the-middle attack in coffeeshops - without 802.1X there's no way to know if that "xfinitywifi" hotspot is really Comcast or not.  Wi-Fi Assistant solves that problem by providing a VPN back to Google's servers.

zOMG so fast!

So far I'm very happy with the Nexus 6.  It's a two year old design but it feels quite snappy.  Google's clearly still putting effort into development, and the Android is pure - no Verizon or Motorola/Lenovo weirdness.  It's a bit larger than I'm used to, so I'm glad I didn't get the Nexus 6P, but I have large hands so it works for me.  Wi-Fi in the 5 GHz band using 802.11ac on the Nexus 6 is fast.  It easily maxed out my 75 Mbps DSL connection in a speed test.

For a while I'd been using an iPad in the evening because the screen was much better than my Droid Maxx.  Now the iPad sits forgotten for days at a time, as I find the Nexus 6 screen good enough to handle almost anything.

K6BJ - 100 Years of amateur radio in Santa Cruz

The K6BJ amateur radio group is celebrating it's centennial on September 17th, and the Santa Cruz Museum of Art & History.  Information can be found at www.k6bj.org - come to the coast and celebrate a century of amateur radio tradition in Santa Cruz County!

• September 17, 11:00am - 3:30pm
• FREE Admission

Santa Cruz Museum of Art and History
705 Front Street
Santa Cruz, CA 95060

Workbench: Screw Terminal Adapters and Lever-Nuts

Having collection of connectors with screw terminals or lever clamps is very useful.  In a pinch you could do a field-repair on a headset, a rig interface, or resurrect a broken power cord with just a pocket knife and a screwdriver.  Here are some of my favorites:

DC Barrel Connectors - these can be used to make a quick disconnect (in lieu of a switch) or an extension cord.  If you just want the plug to match an existing device, you'll have to measure the outer diameter and inner pin.  Most of the time the outer dimension is 5.5mm, and the inner pin is either 1.7mm, 2.1mm, or 2.5mm.

2.1 x 5.5mm paired DC Barrel Connectors
http://amzn.to/2bEavs4

TRS "Phono" Connectors - these are really useful for building test cables or attaching a rig interface to the ADC port on an Arduino or ESP8266.  When you get to the mountain for a SOTA activation and realize your 5 year-old has yanked the end off your headphones, you'll want one of these.

1/8" (3.5mm) Tip-Ring-Sleeve "phono male" plug
http://amzn.to/2bjqfOS

1/8" (3.5mm) Tip-Ring-Sleeve "phono female" jack
http://amzn.to/2bj6JVy


For pocket tools, I prefer the Leatherman ES4 Squirt.  (http://amzn.to/2bEe5lV) It's a ham's dream tool, with a wire stripping jaw, knife, scissors, file, and a screwdriver bit that works well on these screw terminal adapters.

Other interesting stuff....

Wago Lever-Nuts - these are really useful for quick repairs or experiments where you want to easily connect and disconnect wires.  You can use them to quickly add sections of wire for tuning dipole antennas.  Lift the lever, slide in a wire (or wires plural) and drop the lever - done.  Made a mistake?  Lift the lever, change, drop the lever.  They'll handle up to 400 VAC and 20 amps, so they can be used for household electrical repairs or rig power cords.  I keep a handful of these in my field bag, some my glove compartment, and a bunch on my bench.  I prefer the newer 221 Series because the lever is wider and easier to manipulate.
http://amzn.to/2bEcNY3

BNC Female w/ screw terminal - these are 75 ohm, designed for CCTV installs, but for receiver testing or low-power transmit they'll work OK.  Be aware that some adapters like this actually have baluns, which you don't want for RF testing.
http://amzn.to/2bE9Yq1

RJ45 screw terminal plug - kinda bulky, but it's great for designing cables on a bench.  When I'm done and have a working design, I build a real cable using CAT6 and an RJ45 crimper or a punch-down terminal block.
http://amzn.to/2bJ6pxr

Repost: How to fix a Toyota Brake Light

Note: This is a repost/update from my old blog. 

Toyota Highlanders are well made cars - I bought a 2004 for my wife who later upgraded to a Sienna minivan, so I took the Highlander for myself.  It's at 130,000 miles and still going strong.  However, apparently they have a known problem where the brake lights on one side will intermittently stop working.  I've had people pull up next to me at stop lights and tell me I have a light out, then I get home to find the light is fine.

Then recently the light went out and stayed out.  I replaced the bulbs but they remained out.  Fuses were fine, my trusty Fluke 77 said voltage was getting to the assembly.  Posters in Toyota forums said that dealers are asking $40 - $140 for diagnostic, plus possibly $300 to replace a "circuit board"...?  Sounds like a scam to me.

I did some searching online and found reference to how the contacts on the bulb holder will get compressed and not make proper contact. (Kudos to Berto for the original post and Kujath for the photos.)  Kujath suggested using a flat-blade screwdriver to bend the contacts a bit, but I think a needle-nose pliers works better since you can control the amount of bending.  I did both bulb holders and the lights are working just fine. 

Use It or Lose It : Google makes a play for part of the 3.3 GHz amateur band

I've presented several times at Pacificon on the topic of spectrum auctions and the threat to amateur radio's allocations.  In my talk Ham Radio Must Die (So It Can Live) at Pacificon 2010, I specifically talked about the threat to the 3300 - 3500 MHz band.  The threat increased exponentially when the FCC converted the 3500 MHz band to the Citizen's Broadband Radio Service for use in heterogenous networks and densified mobile data systems, and now Google is asking the FCC for permission to test a wireless last-yard technology for delivering Google Fiber service in the upper half of the 3300 MHz band.

In my Pacificon talk I pointed out that the 3300 MHz band is almost never used, and the possible auction valuation to commercial users is very high.  If we presume a $2 per MHz-POP auction price (which is about what the AWS-3 commercial carrier spectrum went for) and a US population of 320 million, the value of the 3300 MHz band is $128 billion.  The AWS-3 auction, record-setting though it was, only raised $47 billion.  For a government $19 trillion in debt, $128 billion isn't much but it's a start.  Google could afford to buy that spectrum, and with the unprecedented access it enjoys due to the revolving door between itself and the White House, it has the political clout to make this happen.

There are just over 800,000 licensed amateur operators in the USA.  $128 billion puts the value of our 3300 MHz band at $160,000 PER OPERATOR.  For something we never use.  I'd be willing to say (and I'm being very charitable in this estimation) that 0.1% of all US operators make use of the 3300 MHz band.  That's $160 MILLION PER ACTIVE OPERATOR.

I'm not saying what Google's doing is right.  If you think it's wrong, file comments with the FCC.  I'm saying what they're doing is not surprising, and that I predicted this would happen six years ago.

HamRadio360 Bling

Came home today to find a package.  Inside was a HamRadio360 sticker and a hat - and the hat is personalized my callsign!

Want a hat for yourself?  Shop now

Talking Maker Faire and IMS2016 w/ George KJ6VU

This week's HamRadio360 podcast contains a segment where +Beric Dunn K6BEZ and I were interviewed by George KJ6VU about the Bay-Net amateur radio project at +Maker Faire and continues with discussion about the panel I moderated for the +IEEE International Microwave Symposium.  The audio for the panelist presentations is in the podcast, and the presentation PDFs are available online in my previous blog post.

Special thanks to Cale at HR360 (nee the +Fo Time Podcast) for covering this.

How To Remove a Flow Lock Without a Key

During the drought I bought a Flow Lock to prevent people from helping themselves to my water.  They have an interesting magnetic key system and seemed like a good idea.  However I found that over time the tumbler mechanism gets corroded and then it won't unlock - even with a key.

The first time it happened I was able to unlock it by spraying WD-40 and tapping it with a small hammer.  The next time it got stuck nothing worked.  My option was to replace the entire faucet, or find a hack.

The Flow Lock tumbler mechanism, when engaged, couples the outer green metal shell to an inner metal fitting.  When the key isn't inserted. the outer shell spins freely, preventing removal.

My solution was to drill through the outer shell to the inner fitting, and then run a deck screw through the two holes.  This couples the shell to the inner fitting and it came off easily.  Side note: I was amused by the product video for this which claimed that a Flow Lock (also known as a "Spinsecure Faucet Lock II") is "virtually impossible to remove without the key" - I did it in two minutes with basic tools and a 5 cent deck screw.

Tips for doing this:

1. Use a 5/64" drill bit designed for metal work.
2. Drill into the center of an indent on the outer shell.  It doesn't seem to matter which indent you choose.  
3. Maintain steady pressure on the drill.
4. Stop periodically and cool the drill bit with spray lubricant or machine oil.

Disclaimer: Stealing water is illegal.  Destroying private property is illegal.  This hack is intended for people who own Flow Locks but can't get them off using their key.  

Field Day is here!

Every year the amateur radio community conducts Field Day - one part contest, one part public outreach event, one part campout & BBQ, and four parts awesome.  Bay-Net hosts a Field Day each year, operating as K6SRA.  For the past few years we've been setting up in a parking lot of the Almaden Quicksilver Park in San Jose CA - and this year is no exception.

For some Field Day is serious stuff - massive operations running 24 hours through the day and night, generators and amplifiers and stacked Yagi antennas, with operation coordinators whose sole purpose is to encourage the radio ops to work stations and log faster.  This does not sound like fun to me.  K6SRA Field Day often devolves into an impromptu technical session where the radios sit idle while we pore over the details of some homebrew project.  Our Field Day operation has jokingly been called "Hot Dogs and Radio - in that order".  For many of our members, busy as they are with work in the always-hectic Silicon Valley, Field Day is a chance to relax and catch up.

This year we plan to shift one of our HF stations from phone to digital on a station created via the excellent Raspberry Pi hacking skills of +Beric Dunn.  I figure the kids will like this better, since it's a keyboard and not a microphone they'll probably be less reluctant to get on the air.

Using Amateur Radio to Enhance Engineering Education @ IMS2016

On Tuesday May 24th I moderated the panel "Using Amateur Radio to Enhance Engineering Education" at the 2016 International Microwave Symposium, hosted by the IEEE.  My panelists were all university professors who have integrated amateur radio into their engineering courses.  As discussed in my article "Amateur Radio in Education" (IEEE Microwaves, April 2016) the panel discussion centered around the value of hands-on understanding that amateur radio brings to engineering students.

Each school has its own implementation of amateur radio into their curricula.  UC Davis uses amateur radio for projects that need transmission i.e. to control drones.  Tribhuvan University uses amateur radio as a tool to teach RF principles, and for humanitarian purposes during earthquakes.  Carnegie Mellon University (both the Pittsburgh and Silicon Valley campuses) have active repeaters and host Field Day sites.  Cal Poly SLO also has a repeater, but they also use amateur radio so much in their courses that freshmen EE undergraduates are required to get Technician licenses - and I'm told that in the coming school year they'll begin requiring graduate students to get their General Class licenses.  I've named this policy the "Derickson Doctrine".

Presentations from each of my panelists are available for download:

Dr. Dennis Derickson AC0P, Cal Poly - San Luis Obispo (download)
Dr. Bob Iannucci W6EI, Carnegie Mellon University - Silicon Valley (download)
Dr. Xiaoguang Liu AI6DW, University of California - Davis (download)
Dr. Sanjeeb Panday 9N1SP, Tribhuvan University - Kathmandu Nepal (download)

Note: This panel was reported by ARRL news release thanks to Ward Silver's help.

Bay-Net at Maker Faire 2016

Maker Faire 2016 in San Mateo CA is complete.  We got a lot of very interested visitors to the booth, and a good portion of them were either not hams or were "ham-curious".

This year's focus for Bay-Net at Maker Faire was Software-Defined Radio and our projects are loosely grouped into three subtopics:

• Show use of low-cost SDR hardware with microcontroller platforms, primarily Raspberry Pi.  These projects are primarily focused on doing basic tasks like filter analysis, receiving FM radio, etc.  We're also showing use of low-cost SDR hardware running with inexpensive Android tablets such as Amazon's 7" Fire which often sells for only $39.99 and can be used to build a basic spectrum analyzer.
• Show applications of SDR hardware running on microcontrollers to do things like build APRS trackers, run azimuth/elevation rotors for tracking satellites, receive ADS-B info from commercial aircraft, and more.
• Show higher-end commercial SDRs for performance applications such as monitoring LTE.

Special thanks to the team that worked hard on this event: +Beric Dunn, +Bernard Van Haecke, +Derek Kozel, +Marcel Stieber, +Kenneth Finnegan, +Maria Pikusova, and Bob Somers.  In the days to come I'll be posting links to info about these projects, so follow and keep watching this blog.

Presentations
Beric K6BEZ : "Getting Started With SDR"
Pieter KK6VXV : "Receiving WX Satellite Signals w/ SDR"

Software/Apps
SDRTouch - Spectrum Analyzer app for Android on Google Play
GQRX - Spectrum Analyzer app for Linux on gqrx.dk
GNU Radio Companion on gnuradio.org

Hardware
SDR dongles (RTL-SDR, NooElec, etc.) on Amazon
Raspberry Pi 3 on Amazon
Raspberry Pi Touchscreens on Amazon

Update 22-May - Added presentation from Pieter and link to SDRTouch.  
Update 23-May - Added team roster, hardware and software/app sources