Monday, June 24, 2013

W5MPZ Field Day!

I had the honor of joining the Sandia National Labs Amateur Radio Club's (W5MPZ) Field Day activities. The team consisted of 20 or so people who sought out this ham radio haven of a campground in the north edge of the Zuni Mountains near Gallup, NM. There was a lot of open space, many places to set up tents, and best of all, tall pine trees to hoist antennas. 

Our station was active for almost 24 hours, minus a lull at about 1:10 am Sunday morning. Our backup arrived at around 2 am, which included Brian (N5ZGT, Rocky Mtn Division Director), who just got back from a Turks and Caicos island vacation (or DXPedition, you might say), and Scott (N5SQR) who worked PSK and SSB.

Setup and Operation 


Before I arrived, the triband TA-33 beam was set up on poles over a center stake pounded in the ground.  It was rotatable by simply spinning the mast. The guy ropes were left slightly loose so that it's rotatable, and they spool and tighten around the mast when you rotate it. They tighten just enough to cover the northerly half of the horizon without much added tension.

TA-33 with the 80m windom in the background
The beam was top. It was fun but frustrating to hear a section you haven't worked on the back side of the beam, run out, turn it, and discover the station disappeared completely. 


The 40-50' tall Ponderosa Pines were more than adequate antenna masts. Our method of pulling lines over the trees was with a spud gun -- a PVC contraption with an air tank, electric valve, and 3' long barrel which shoots a PVC slug with fishing line attached to it.

On my first shot, I got over this tree and the line sat perfectly on the brown number post.

The perfect shot.
After shooting the line over the tree, we'd tie and pull thin twine to it, then pull heavier rope to attach to the antenna. Repeat for the other side, and hoist away.

Old Glory on our 80/40 trap dipole

We had an 80/40 m resonant trap dipole on one tree, and the other was an 80m Carolina Windom. They were both oriented for maximun E-W reception and did a great job.

RPi camera

 A nifty setup was a motion sensitive camera connected to a Raspberry Pi. It snaps photos when it sees movement, and stores them on an SD card and posts them to our LAN. The router was for the LAN for syncing our logs.


We were 2A, so we had 2 stations on the air, all supported by batteries. We operated SSB, CW and PSK31.

Scott, N5SQR working SSB
After setting up the last dipole, we began calling CQ on a clear frequency a few minutes before Field Day start to secure our spot in chaos. Once it began, signals filled the band but we had an interestingly slow time throughout the day. We shifted operators on the top of the hour, usually having a logger and radio op on each station. We made around 150 QSOs on SSB, CW and PSK31 before sunset.

No field day station is without its problems. We were lucky to only have minor issues, like the logs not syncing or the digital station computer interface not working. These were easily and promptly fixed. Everything else (except for the band conditions) was perfect.

Our ops came from all areas of the hobby. Brian, for example, just got back from Turks & Caicos, and worked hordes of stations from VP5-land, while Seth never worked a contest before being a technician.

Brian and Seth teaming up to send Radiograms for bonus points
Seth taking names and gettign mults on the voice station
Seth quickly caught the Field Day bug and worked the 12-1am shift by storm, and eventually took both working and logging on the voice station on solo.

It was very cool to see him warm up to the air and get excited to work stations. It reminds me of my first Field Day, where I was thrown into the action and started racking up QSOs as fast as any other operator after only having a few hours to figure it out.
Seth also worked PSK31 after showing him the macros. He first though it was going to be too difficult, like CW, but was amazed at how simple it is.

The county sheriff got the call from us to visit the site. He visited on his regular patrol and we explained our operations to him. He was certainly impressed.

A visitation by the local sheriff


The Arrow LEO-SAT yagi and other antennas in the background

Sat Station Setup -- FT-817 for RX and an 897 for TX
My job at W5MPZ was to bring a satellite QSO to the log for an extra 100 points. Unfortunately, this didn't happen.

I had several attempts at SO-51 (the only FM satellite), VO-52, FO-29 and the zombie AO-7 (all SSB/CW transponders). I had most luck with the SSB satellites but had problems in being able to hear myself.

To work the SSB satellites (all but SO-51) you need to know where your signal ends up after it gets translated to the other band. For example, FO-29's uplink band is 145.8-145.9 MHz, while the downlink is 435.9-436.0 MHz. One would think the 100 kHz passband would be linearly related, e.g. I transmit on 145.85, and hear myself on 435.95, but this isn't the case. The doppler effect causes the frequency to differ by up to 500 kHz on UHF, so you need a way of calculating doppler, or simply finding yourself.

My technique was to spin a carrier through the passband until I heard it on the downlink, and switch to SSB to call CQ and tune into myself. Upon the switch, I lost myself.

I figured out the solution on the last pass of the weekend. The FT-897 has a feature in SSB mode that allows you to send CW at your tone frequency. So if I'm on 145.000 and have a 700 HZ CW pitch, it would send it at 145.000.70 MHz. Therefore, if you were tuned into 145 MHz on another rig, you'd hear that same pitch. All I had to do was zerobeat on the flipped bandpass, and call away. I finally heard myself repeated by the satellite, but didn't have any replies within the last 5 minutes of the pass.

It was worth the effort (and in hindsight I should have just worked the ISS's message system via packet)!


The underlying point of Field Day (aside from preparedness) is to have fun. W5MPZ did exactly that. Our support team of family members kept us well fed, watered, sheltered, and our batteries charged. One could not ask for a better place to set up and operate from, and the weather (despite being cold in the mornings) was amazing - not having wind and the 100°F temperatures to contend with was a huge relief.

I'm not sure of the final QSO count or score, but we only missed a few sections in Canada - NT, MAR, and ONN I believe -- like we expected. Field Day isn't a contest, so the score isn't important to me or any of the operators aside from personal club goals and whatnot, so that wasn't a worry. What matters is the coming together of like-minded people to getaway from the daily grind, have a ton of fun, share stories, and work stations.

Friday, June 21, 2013

If You Had Radio Eyes...

It's always been a dream of mine to put on glasses that allow you to see only waves of RF emitting, reflecting and illuminating the world around you...this would make my job so much easier too!

Well, there just so happens to be such a thing that allows you to see only requries about 3 acres and 250 antenna elements, a supercomputer and a fast internet connection.

The LWA near the VLA
The Long Wavelength Array is a seemingly random assortment of crossed dipole pairs with a frequency response of 10-88 MHz. Every antenna is separetly fed into a giant computer that correlates and beamforms the array into a giant RF eye looking at the sky.

LWA Dipole Detail with the VLA in the background
And by eye I really mean it sees the RF world above it in real time:

Above is a real time view of the sky above the LWA (hit F5 to refresh, I dare ya!). During the day you can see the sun and several radio sources like Cas A, Tau A, and Cyg A which are galaxies, pulsars, and other nebulae of ridiculously "loud" RF emitters. Also, at the top and top left, you can see RFI from the VLA site, which is one of the things we're working to alleviate.

Another cool thing it can do is plot spectrum over the whole day:

This shows the intensity at all frequencies between 10 and 90 MHz over a 24 hour period starting at 17:00 PST 11 July 2012. You can watch the nighttime MUF drop between 00:00 and 06:00 PST, and surge again at sunrise. Other strange and interesting patterns exist as well -- check out the index at and see what you can find.

Ckeck out their website at and read technical information about the LWA here, and an even more technical dissertation here.


Thursday, June 20, 2013

Fire, Lightning, Wind and Dust: New Mexico Weather

New Mexico is dry. I was floored when it rained three days ago. But for 11 months out of the year, the air is dry, the sun is bright, the clouds are facetious, and everything's on fire. 

Smoke plume from the 30,000 acre Silver fire
Smoke fills the horizon
 Such is life in NM. The 10% humidity caused me some pain and suffering for a while, but I seemed to got used to it. I used a lot of normal lotion, which wasn't the best idea for being out in the sun so much.

Currently, a large chunk of the Gila mountain range is on fire, but thankfully few people live in the area. The Silver fire (named because its near Silver City, NM) is currently at 32,000 acres, making it the biggest fire in the US. From atop a VLA dish, you can see the smoke plume and the long trail of smoke being carried by 30-40 mph surface winds. It's quite dark in Truth or Consequences.

Aside from the fire, the plains of central New Mexico have a variety of weather, typically involving some kind of dust and lots of wind:

Dust carried aloft by 40 mph winds
We even have tornadoes of dust! (Seriously, some of them are big enough to cause damage):

A particularly strong dust devil with a well defined center column

Then, all of a sudden, it storms:

A snowstorm to the's a rare event to see precip actually get to the ground.

Above, you see it's snowing. Snowstorms in the southwest isn't a myth after all! Just last year, a snowstorm dumped 2' of snow on Socorro, NM.

Typically though, the air is so dry that any precipitation just evaporates before it hits the ground. This phenomena is called virga, and is the sole reason why the clouds are so facetious. What does hit the ground are tendrils of lightning, graupel -- basically mini snowballs from the sky -- and hail.

A tendril of lightning betwixt two VLA dishes
In 2004, hail fell with a vengeance:

So its dry, its dusty, windy and usually boring (minus the bits of hail, getting caught in a haboob, and waking up to lightning barrages)...but now is the season for rain. And we're in dire need. NM has been in a 10 year drout, and wells are drying up like int he community of Magdalena, NM, just east of the VLA.

Locals believe that July 4 is the day which marks the start of the monsoon season...don't take monsoon to seriously though, it's not like the monsoons of India and Asia. They may dump 2" of rain, but that gets sucked up so quickly by the dry, absorbent dust and flora of the mountain ranges that it was like it never happened the next day.

We'll see what the skies bring.

Tuesday, June 18, 2013

Revitalized Jamesburg dish Now Sending Texts to...aliens?

The once famous Jamesburg dish (wikipedia link), located in Carmel Valley, California, was restored and used by hams to do EME experiments and events after its prime mission to capture and relay communications from Apollo 11, Tiananmen Square, and Intelsat came to an end.

The massive 30m wide by 100ft tall Jamesburg Dish

The site was later bought by Jeffrey Bullis, sold the old communications equipment for scrap, and turned into a private nerd-topia. After his youngest son died, he sold the site and put it up on .

A private company calling themselves Jamesburg Earth Station Technologies, LLC bought the site. This company spawned another, called Lone Signal, LLC. The executives come from diverse backgrounds -- entrepreneurs, fashion design, and hospitality execs -- along with a team of PhDs and engineers. No hams that I know of, though.

Anyway, the idea behind LoneSignal is to allow people to send texts and photos to star systems with potentially habitable planets. The current one is pointed at Gliese 526, a red giant star 17.6 light years away that's believed to have a planet inside it's habitable zone.

The first text is free, but the rest are about $1 a piece. You can buy bulk credits for a discount.

The 30m wide Jamesburg dish will be using a 2KW C-Band transmitter (6700-6875MHz) and will send the coded texts in CW and FM formats. Interestingly, in the FCC-OET Program Description, they'll be using an Icom ID-1 to modulate the FM signal. I'm sure the aliens are going to have a tough time demodulating D-STAR. :D

Their experimental license application is located here.

Using some quick math, the dish should provide about 64 dB of gain, and with 2 kW input, that translates into an EIRP of 5,931,547,041 watts.

That's 6 gigawatts.

TL:DR: In 17.6 years, the Gileseans may get my CQ. I hope they QSL via the bureau.