Portable ops washout

I had Thursday and Friday off of work for the 4th of July, and my wife only had Friday, so Thursday was a “free” day for me. Free after I took the car to get smogged and took my son to a doctor’s appointment, that is… So I decided to try some portable ops at the beach. My ATS-4 setup was at work, but it was so windy I was planning to stay in the car anyway, so I just took the Field Day setup – K2, tuner, battery, end-fed antenna, key, and mic. I drove 20 minutes to the spot I had in mind, parked the car… and realized I had left my antenna support pole at home. So 40 minutes later I was back and ready to set up.

I lashed the pole to a fence post in the parking area and rigged the antenna as an inverted V again, as I had on Field Day. But when I checked it on the antenna analyzer (without the tuner), it showed pretty terrible (over 7:1) SWR on every band except 10 and 17. This isn’t what I remember Rob seeing when we tested the same setup before Field Day, although then we ran the wire as a sloper up to the top of the pole. Anyway, I decided to try 17m, but when I turned on the radio it came up on 15 and, even without tuning, I heard CW. So that was promising. But I switched to 17, tuned the antenna, and then scanned the phone subband to see what I could find. The first signal I came across was S57DX, Slavko, in Slovenia. Easily a 57 to 59, and working a modest pileup.

I tried repeatedly to QSO with him, but he never heard me. I tuned elsewhere around the band and tried to work some other stations but had similar lack of luck. Over the course of about three hours I heard several Brazilian stations (with World Cup special event calls), Cayman Islands, North Carolina, and Massachusetts (the latter two working the 13 Colonies special event). I tried numerous times to QSO with all of these, but didn’t get so much as a QRZ. I also spent 20-30 minutes calling CQ in between other stations, but got no takers. All of this was on phone. When it was almost time for me to pack up and go home I switched to CW just to see if I could get spotted on the Reverse Beacon Network, but even that turned up nothing on both 15 and 17m.

Just before I shut down I tuned around and came back to S57DX in Slovenia. I heard him say he was going to go QRT soon and just work a few more stations, his pileup was trailing off. So I tried again to work him, and even at the end when he had no other callers, he just couldn’t hear me at all.

After the enjoyment I had making a decent stack of contacts on Field Day, I was pretty disappointed to have nothing to show for three hours of operating on my day off. I did look at dxmaps.com and there were not very many spots showing at all. So by that metric, the bands did not seem very open. Maybe all the stations I was hearing were QRO. I’m also curious about why the antenna seemed to look so poor on the analyzer. I think I need to look into modifying the end-fed matchbox to use a counterpoise. As designed, it uses the coax braid for that and recommends a 25′ length. I only use a 10′ piece normally, and don’t really want to cart around extra coax and have to set up the matchbox farther from my rig just to make the antenna more efficient. I’m not really sold on the idea of an antenna system that requires a tuner. I’m always operating at QRP power, so if the tuner is just giving me a nice match but the actual antenna SWR is 5:1 or 7:1, that seems kind of a waste of time. Perhaps instead I should try constructing some band-specific matchboxes that don’t require the tuner.

It would also probably be beneficial for me to play around with EZNEC or some other antenna modeling software. I tried to use it once but couldn’t get the hang of it for some reason. Maybe it’s time to make another attempt (now I know a lot more hams who can probably help me with it). A I think back on how I was set up, I wonder what direction my signal would have been going. End-fed antenna, inverted V, with the sloped sides facing north and south… I wonder if my takeoff angle was not even remotely easterly, as I was trying to work stations in that direction…

About the only other thing I can mention is that I noticed an interesting variety of ignition noises from cars passing my operating position. There was a multilane road just behind where I was parked. Most cars generated a mild buzz. Junky old pickup trucks generated a nasty hash. And electric cars generated a unique steady hiss as they passed.

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A video from Field Day

Rob, AK6L, made a short video of our Field Day operation. Check it out here: https://www.dropbox.com/s/dqdd4e5glemdbtv/20140628_131402_001.3gp

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Field Day 2014 after-action report

All my careful preparation paid off. On Saturday morning I was up and out the door only a few minutes later than I hoped to be. I backed out of the garage and tuned the radio to our pre-arranged repeater just in time to hear Wil and Rob making first contact. Wil was already en route, and Rob was just leaving his house. Fortunately my run across the bay was free of traffic, and my phone navigated me to the parking area flawlessly. Wil was a few minutes ahead of us up the trail, I met Rob in the parking lot and we set off. I was able to fasten my antenna pole to the side of my pack, and I brought my trekking poles for the trail, which I was really glad of because the first third of it was littered with loose hunks of rock. I wish I had a picture of myself on the trail because I’m pleased with how compact my setup was.

The hike to our chosen site took 20-30 minutes and was modest on the arduousness scale, in my opinion. Wil was waiting for us at the top, so we got to work setting up our gear. Wil and Rob set up the sun shelter and I cabled up my radios, then got to work putting up the end-fed antenna. I lashed my support pole to a nearby bench, tied one end of the radiator to it, and extended the pole, but it quickly became apparent that it wasn’t far enough from our operating position; the wire was going to trail on the ground too much. After consulting with Rob, we decided to run the wire as an inverted V. I attached the 9:1 un-un to the top of our sun shelter and ran the radiator through the eyelet at the tip of the pole, then extended it up. After some adjustments it looked great, with the loose end tied off to a nearby bush. A 20′ length of coax to the rig completed the setup.

I was amazed at how perfect our site was. The view west was of the San Francisco bay and skyline, Alcatraz, and the Golden Gate bridge. To the east we could see reservoirs, and then rolling hills stretching away to the horizon. The ridge we were on was at about 1500′ of elevation and dropped away steeply to either side, so I expected good takeoff angles for our antennas.

Pretty soon we were all set up, and I think we were on the air by 11:30am, 30 minutes after the official start. I took 15m CW, Wil took 20m phone and Rob took 40m PSK31. I made my first CW contact after a few minutes, but it was tough. I’m rusty after a few weeks off, and even though the other station was slow and patient, I was flustered and could hardly even ask them for repeats correctly. I’m lucky they just sent them anyway a couple of times, eventually I got it nailed down. But it sapped my confidence a bit, and I spent the next few minutes playing around with recording a CW macro to call CQ for me, and calling a few times with no takers. I decided to test out the new mic setup for the K2, so I went up to the phone band and found a loud station calling CQ. I called back, and after a couple of tries I worked them. Success! I continued up the band working stations that I heard calling, and racked up 10-15 contacts while running 10 watts. I was impressed.

Once the stations petered out near the top of the band, I tuned back down among them, found an open frequency, and decided to try calling CQ a bit. It didn’t take long before someone came back to me, so I kept at it, holding the frequency for awhile and making another 10 or so contacts that way. I called nonstop with just a short pause to listen for people coming back, and it seemed to work.

Wil seemed to be having OK luck on 20m, but it was challenging because it was wall to wall stations, many of them really loud, and he was just running 35 watts. He tried 10m but it was dead, and Rob was hearing no PSK31 on 40m, so they switched – Rob went to 20m and Wil went to 40. On 20 Rob heard massive amounts of PSK31, but struggled to work any of it using his Nexus 7 tablet and DroidPSK app. The touch interface of the app made it hard to select signals to QSO with, and it was easy to tap the wrong place and exit the app entirely, which happened once in the middle of a QSO. This despite the fact that he had a bluetooth physical keyboard attached. If the app had had a keyboard shortcut mode that removed the need for touch input he might have had better luck.

Wil left around 2:30pm having made 10 contacts or so. Rob and I stuck around until 4, with him only making 2, and me making 30+. Our gear packed away pretty easily and soon we were back at the trail head and on our way home.

I’m really pleased with how Field Day went this year, speaking for myself at least. Last year I think we spent more time setting up and breaking down our gear than we actually spent on the air, and we didn’t make many contacts. Obviously I’m pleased to have made a decent haul myself this year, maybe Rob and Wil would say they were more disappointed not to get very many. But you couldn’t beat the location or the weather, that’s for sure. It was nice being in a public spot, and we had quite a few hikers ask us what we were up to, and everyone was interested. Rob had a good spiel to explain briefly what it was all about, he was great for PR!

I’m also really happy that I put in the effort to perfect a simple portable station with power and antennas that could be set up very easily. As my friend Majdi, N0RMZ, pointed out, “You live in a fault zone.” I’ve made other earthquake preparations of course, but HF capability could come in handy should there be a “big one” while I’m living here. In thinking about it, now I understand more clearly why the ARRL terms Field Day a “preparedness exercise,” and awards bonus points if you pass message traffic. Practicing the act of communicating, including speaking clearly, confirming a message and writing it down, is fundamental to being useful in a disaster scenario.

For next year, about the only thing I would do differently is bring only one battery and also leave the extra 20′ length of RG-8X coax I brought at home. The battery was a significant extra weight in my bag, and I only brought it in case Wil needed it for his phone station. For almost 5 hours of use my battery only drained a little over 1/4 of a volt.

So that’s a wrap until 2015! Now here are some photos.

Gear waiting to be set up


Setting up the sun shelter


San Francisco, Alcatraz and the Golden Gate bridge to the west, and… the rest of America to the east.

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On the air! Rob’s Buddistick to the left, my end-fed wire coming down in the middle, Wil’s Buddipole in the background/right.


The whole site. My end-fed in an inverted V configuration to the left.


Makin’ contacts!


My operating position.


Public information flyers for a 100 point bonus.



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Field Day 2014 prep

For my previous two Field Days I set up on the roof deck at my rowing club on San Francisco bay with Rob, AK6L. But the site has some drawbacks: it can be incredibly windy, we have sometimes had bad QRM from local electrical sources, and the physical act of setting up and breaking down gear (hauling it up three flights of stairs and clamoring around on a roof) is very arduous. Last year we spent more time setting up and breaking down than we spent on the air, with precious few contacts to show for it.

This year there was some talk that Rob’s dad would fly out from Minnesota for the event, and my co-worker Wil, W6FU (yes, really), was also interested in joining us. He and Rob both live in the East Bay, so it seemed like picking a site there would be more fair to them from a travel perspective. After a bit of Google Maps research we homed in on the Sea View trail inside Tilden Park in Berkeley. It seemed to afford great elevation for signals from the east, good distance from any household electronics that could cause QRM, and reasonably easy access. Rob agreed to scout the area on foot ahead of time, and reported that there was a prime spot at the top of the ridge with great views and a picnic table and benches we could make use of. His attempted hiking route was pretty arduous, but after further research he found another that looked a little easier, so we settled on this for our site.

Rob pointed out that this operation would be really in the spirit of Field Day, as we would be, “In an actual field!” We would also be using battery power and portable radios and antennas. The plan was for each of us to bring his own self-contained station. Rob would bring his KX3 and Buddistick and work PSK31, Wil would bring his FT-857D and Buddipole and work voice, and I would bring my K2 and an end-fed half wave wire and telescoping pole for an antenna, and work CW.

I didn’t have a battery suitable for running my K2 for long periods of time, I thought, so I invested in two 7Ah SLA batteries. Both together would be way more power than I needed, but I got them on Amazon for $22 each and free 2 day Amazon Prime shipping. Wil only had one SLA, and since his rig can put out 100 watts, I thought having a spare he could use could come in handy. I bought spade connectors and made up some spade to PowerPole cables, and also bought a PowerPole splitter so I could power my K2 and my LDG autotuner. But I realized that if I wanted to run the two batteries in parallel, the easiest way would be to use some spade T connectors. I ordered some from Amazon Supply, but for once Prime shipping let me down and they did not arrive in time.

I built a matching transformer for an end-fed antenna recently, and tried using it at home with a ~30 foot long wire running up the back of my apartment building to the roof. But SWR with it was poor on all bands (though it is intended to be used with a tuner) and it just seemed deaf. I heard little and only received one or two spots over numerous operating sessions. I was worried that it wasn’t going to be suitable for Field Day. It was my birthday a couple of weeks ago so I took the day off work, and Rob offered to help me set up the EFHW out in the open and see if we got better results. I read on W2LJ’s blog that a 53′ radiator for it is one of the optimum lengths, so we went to the beach at Crissy Field on San Francisco bay and set up with that. My antenna analyzer showed SWR below 2:1 on most bands, except for 20m. We didn’t make any contacts on that outing, but it seemed like proof that the antenna would work. Just in case, I also brought my 20m dipole setup to Field Day.

I packed all my gear on Friday night so that on Saturday morning I could just get up and go. Into my big frame pack went the batteries, log book, K2, tuner, HT, various coax lengths (mostly RG-316, which I am now a big fan of for portable ops), power cables, antenna wires, headphones, mic, key, sunscreen, and two 750ml bottles of water. I also packed a sandwich and a bag of cherries for fuel.

I bought the Elecraft hand mic kit for my K2 a couple of years ago but never got around to using it. Doing so involves opening up the radio and soldering a bias resistor across two pins on the microphone jack. I impulsively decided to do this at 9pm Friday night, in case I wanted to operate voice during FD. I pulled the K2′s front panel off easily, but then I noticed that one of the screws that holds the control panel board onto the housing was loose. I went to tighten it, and it wouldn’t. Investigation revealed that it threads into a standoff with two lock washers on top. Visions of these falling off and shorting things when I was operating would not allow me to just leave it alone, but fixing it was going to require removing all the front panel knobs so I could put pliers to the spacer while tightening the screw. Thus a five minute soldering job ended up taking me an hour. I didn’t get to bed until midnight.

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QRP On Vacation

Recently I went to Boston to visit my parents for 10┬ádays. I like to get on the air from different locations, especially the east coast of the US because I can hear Europe much better there. On one previous trip I brought almost my entire home station with me – it was pretty ridiculous. Other times I have borrowed a friend’s Norcal 40A CW transceiver, but my CW skill was much too weak to make much use of it. But a few months ago I finished building a KD1JV ATS-4a transceiver, and I started using it at lunch time on work days, trying to practice CW regularly. I’ve gotten good enough, and come up with a portable station compact enough, that I was looking forward to getting on the air on this trip.

My portable station now consists of the ATS-4a, a no-name 3Ah LiPo battery, 10 feet of RG-316 coax, a simple plastic dipole interface thingy, and an American Morse Equipment Porta-Paddle. With a properly tuned dipole this setup works really nicely and is very light. I also had been thinking about buying an antenna analyzer, so before this trip I finally pulled the trigger and bought a YouKits FG-01A.

Last time I visited my parents I brought some wire and cut a 40 meter dipole, and since I had some left over I went ahead and made up 20m and 15m ones as well, and left them tucked away for a future trip. So this time I thought I would try an antenna design I’ve always been interested in, the fan dipole.

My parents have a 3 story house with a small porch facing the back yard on the middle floor. They have a large yard, with a tall tree on one side and a garage on the other. I thought I would try to hang the dipole using the tree and garage as supports, with the feedpoint near the porch, so I could sit there or in the living room to operate. After measuring things out and rummaging in the garage for useful items, my dad and I took a trip to Lowes and bought 100′ of clothesline rope, a ball of twine, a package of small zip ties, some heavy steel washers, and some $5 wire strippers.

My dad helped me rig everything up, which was cool. I explained antenna resonance and why the lengths of the wires mattered. One problem we had was that there is a smaller tree in between the porch and the garage, which was going to make lowering and raising the antenna repeatedly infeasible. This also led me to give up on the 15m wire because there wasn’t enough vertical space for it. Jason, NT7S, pointed out that the 40m wire should also work on 15m because 15m is a harmonic of 40.

In the end I took all the rope up to the garage roof, heaved it over the small tree, and dad pulled it up to the porch. He attached one leg of the 40m wire to the rope with zip ties, then tied the end of one leg of the 20m wire to the rope with 12″ of twine, using washers to weight it down. Then I pulled all that back across to the garage. Then we attached the other wire legs to the remaining rope, I climbed the pine tree, dragging the rope up behind me, and tied it off. My dad lashed a pole to the porch to hold the antenna up a few feet above the railing, I hooked up the coax, and turned on the new antenna analyzer.

The analyzer showed pronounced dips in SWR at about 6.400 MHz and 13.500 MHz. Not bad, just a little too long! I climbed back up on the garage roof and up the pine tree and cut off 6″ from each end of the 40m wire. Checked it again and it was better, but still too long. 7″ more removed, and the dip was right at 7.000! Shortening the 20m wire was easier because it was only attached to the rope at the end. I just cut 12″ off at the feedpoint and it matched up nicely. The antenna did look OK on 15m too, though the SWR was a bit higher, in the 2.5:1 range instead of below 2.

Performance on the air proved that the antenna was working nicely. Over the next few days I made contacts with WA4HHC (FL), WE4G (KY), VE2ZA (Montreal), LZ2RS (Bulgaria), 9A2AJ (Croatia), SM7ZDI (Sweden), HA8WZ (Hungary), RA6AN (Russia), K1USN (Braintree, MA, the next town over!), and K3RNC (MD). Most of these were on 20m, a couple on 40m. I heard many other stations but couldn’t work them, sometimes because they couldn’t hear me, other times they were just going too fast and working a pileup. I made good use of the Reverse Beacon Network, though sometimes I think I spent too much time staring at that and jumping to a spot frequency hoping to hear someone, instead of just calling CQ or tuning listening for callers. Also I had much better luck at night than during the day for some reason, even on the weekends.

It was good to get some more CW practice, and I was really pleased with how well the antenna worked. I would definitely try that design again in the future. It was also cool to see the antenna analyzer in action. Of course there are always things you would try or do differently next time. Because of the layout of things in the yard, the legs of the dipole were not perfectly straight. I ended up with a horizontal V shape, with maybe a 120 deg. opening instead of 180 deg. If I’d had a longer feedline I could probably have made it straight, and I wonder how much difference that would have made.

Also, my parents’ house is built into the side of a small slope. The antenna was probably about 20′ off the ground directly below it, but just on the other side of the house it would only have been maybe 6′ off the ground. I don’t see many options for getting it up higher, although it did occur to me that I could try to hang it up in their attic. That would probably get it more than 30′ off the ground. Could be interesting to try.

Here are some pictures of the setup. First, the SWR plots before adjustment. The frequency shown is where the SWR is lowest.

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Then, the plots after adjustment. Center frequency is set to my desired target, I was still a little long but close enough.

IMG_20140603_135856 IMG_20140603_135911 IMG_20140603_135923

Finally, some pictures of the antenna itself. It’s always hard to photograph wire in the air, though. Note what looks like (and is) an old car rearview mirror on top of the center support pole. My parents are avid bird watchers, and use this contraption to look into bird nests to see if there are any eggs!

IMG_20140603_150703 IMG_20140603_150729

IMG_20140603_150755 IMG_20140603_154731

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Field day retrospective

My first Field Day has come and gone, and with the benefit of a day's reflection I can offer this account of the fun. But first, take a look at my pictures here.

After finalizing our preparations, Rob (AK6L) and I agreed that we would aim to arrive at the rowing club at 10am and plan to be there potentially until 8pm. Field Day started at 11am, but we weren't expecting to break any records or haul in a huge number of points (though I didn't know what to expect really). Rob took Friday off to finish the bandpass filters and also to build an interface that would let him use his aircraft intercom headset with his FT-950. Unfortunately the filters took longer than expected, and the headset interface needed some further tweaking, and Rob was also bringing 3/4 of the gear. As a result he ended up running late, and we didn't get to start setting up until a bit after 12pm.

I made a valiant attempt to string up the shade tarp on my own, but we had winds gusting up to 26mph, and on the third floor of a building on the waterfront it just wasn't going to happen. It wasn't until Nick arrived that we got that under control – it took the loan of 100 lbs of barbell weights to hold the windward corner down.

Once Rob got there we unloaded all the gear from his car, he went and parked, and then came back and started setting up the Buddipole. Nick and I finally got the tarp sorted out, and then I helped Rob roll out the wire for our second dipole antenna (around 100' perpendicular to the Buddipole) and secure the guy lines. We used water-filled patio umbrella bases for weight, a clever idea credited to Rob's girlfriend Denise, who originally suggested it when I was looking for a way to support a free-standing dipole on my old apartment's roof.

Once we got the antennas up we were pretty hungry, so Nick went and picked up some food for us. Rob and I worked on getting all the radios, tuners, power supplies, and amplifiers going. Rob had to make a couple of PowerPole pigtails, and I had to get familiar with his FT-817. We didn't make our first contacts until around 4pm.

Rob used his FT-950 and focused on making phone contacts, mostly on 40m. Just as we got started he encountered heavy QRM across the band. I set up his FT-817 with his Tokyo Hy-Power HL-45b amplifier and focused on making PSK31 contacts. I started out on 15m, but there wasn't too much action there, so I switched to 20m and found a lot more. I made a few contacts, but I was only able to get about 10 watts out of the amp, which made it hard to get through when people were calling CQ, and made it pointless to call CQ myself. Eventually there was someone calling CQ with quite a bit of power, right in the middle of the PSK31 window. Even with AGC turned off, which is how I always operate PSK31, the strength of the other signal attenuated the rest of the band and made decoding difficult. I made a comment about it, and Nick said, "That's what inferior dynamic range looks like."

I had brought my Elecraft K2 with the thought that we would set it up as a GOTA station, to earn a few extra points. In the end, since we were so behind schedule and we weren't sure what antenna we should set up with it, we punted on that idea. Fortunately, I decided to grab the external amp keying circuit that I built for it when I was packing, so we decided to try using it with the HL-45b amp. It turned out that this setup worked much better – I was able to get 40 watts out of the amp, and the dynamic range of the K2 handled the strong signals much better. That was an interesting experience, because I've never had a chance to compare the K2 with any other rig side by side like that. 

At one point in the afternoon, we watched a destroyer sail into the bay. When it got close enough that we could read the number on her bow, we looked it up: the USS Dewey, DDG-105, and Arleigh Burke-class guided missile destroyer. Pretty neat!

KPH, the historic RCA coast station that Nick and I volunteer at, is also the west coast outlet for the Field Day bulletin. Copying it earns you 100 extra points, so I made sure to do that at 6:30pm. I found them broadcasting RTTY on 20m and managed to capture the whole message. At 7:30pm the sun was starting to set, the wind was picking up again, and I remembered that I had told Catherine I would be home around 8. After polling the guys, we decided to knock off. It took a solid hour to break everything down, and that was it for this Field Day.

Time on site: 8.5 hours
Time on the air: 3.5 hours
Transceivers used: 3 (2 simultaneous)
Antennas: Buddipole and 100' wire dipole
Maximum power: 100 watts
Contacts logged: 18
Points scored: 202

In spite of our meager haul of points, I had a lot of fun, and I think Nick and Rob did too. We had glorious weather, other than the high winds, and you really can't ask for a more beautiful spot than the San Francisco waterfront, with the Golden Gate bridge and Alcatraz right in front of you. Still, there are definitely some things that we would do differently next year. For one thing, get there earlier! Of course, next time Rob won't have to custom-build a bunch of filters and and a headset interface ahead of time, and now we know how to set up the antennas. Still, setup definitely took a lot longer than we expected. We also could drop some gear off the day before, to save ourselves some unloading time.

I also think next time we won't set up the tarp. There's a small, empty storage room off the roof deck, where we got power for our setup. We could have just set up in there, except when we first scoped out the building I didn't have access to it, and even when we did, we didn't have enough coax to reach. Operating from there would have saved us a lot of time.

Now I know that my K2 can outperform Rob's FT-817, at least in contest conditions; that's really what the K2 was made for, whereas the 817 is made to be a great portable all-mode rig. Next time I'll probably just use the K2 from the get-go. The other upshot of this is that I know its controls instinctively now. Not only is the 817 new to me, but because of its small size the control interface is very, very menu-driven which just makes it harder.

As Rob said, this Field Day was in large part just a proof of concept for operating from the rowing club. It's obviously an excellent location, weather-permitting, so we're definitely going to try and operate more contests from there. I may even look into operating there just in general, on weekend days, because I'll be able to set up a much better antenna than I have at home. I'm already thinking about what simple antenna system I could keep in my locker for easy setup!

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Field day preparations

Rob (AK6L) and I decided to go for it and work at least some of Field Day this year from my rowing club on San Francisco bay. We met down there last Sunday so that we could scout possible locations to set up. There are several good spots, but in the end we decided to use the top floor roof deck. Although the second floor lounge room with balcony might be somewhat more comfortable, we would probably only be able to set up one antenna, and it would have to run over the patio and down the dock, potentially attracting more attention than I would like. Also taking over a chunk of the lounge room for a day of "CQ FIELD DAY, CQ FIELD DAY" seemed like it would not likely be appreciated by everyone.

Although the roof deck is out in the open rather than indoors, it gives us access to the very large, flat roof, perfect for antennas. After measuring things out, it looks like we can easily set up two wire dipoles at 90 degrees to each other and tune them with our respective LDG autotuners. We're also going to set up a "Get On The Air" station, since we'll be in a visible spot. Rowing club members are likely to drop by and see what we're up to, and having a GOTA table earns us some extra points. If people make enough contacts with it, the bonus is bigger.

I'm going to bring my K2, and Rob is going to bring his FT-950 and FT-817. He just fixed the external amp he has which goes with the 817 (which I fried…), so we'll have a maximum of 15 watts with the K2, 100 watts with the 950, and 45 watts with the 817. Rob is also going to bring his Buddipole portable antenna.

The plan is for me to operate mostly digital, with Rob mostly on phone. Nick says he's up for hanging out and possibly operating a bit as well – at least he'll probably be handy for helping Rob log phone contacts and overseeing the GOTA station if anyone actually wants to use it. I'm not sure if I'll use the FT-817 for digital, in order to get some more power out, or the K2. I'm more familiar with the K2, but it is limited to 5w for full duty cycle modes like PSK31.

I'm going to bring all my portable antenna gear, and Rob is currently working on building a set of five bandpass filters (necessary for operating two or more stations in close proximity). We'll have mains power on hand, and I'm bringing a big tarp to give us some shade. Basically, although I'm sure we're going to forget some things, we should be able to run a pretty nice setup there. I'll be curious to see how well our signals get out from there, given our proximity to San Francisco bay, and also if we experience any QRM. We should have an excellent takeoff angle to the east, but there's a hill just west of us that might cut down our trans-Pacific DX. We'll see.

I'm excited!

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Finished tapping the heatsink

Here are a couple of shots of the amp mounted on the heatsink. I was right that the PA transistors are sitting too high at the moment, so I'll need to remount them so they sit flush with the heatsink.



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Amplifier and other news

I finally realized a few weeks ago that I have way too many ongoing projects in my life. I've taken on various volunteer responsibilities at the rowing club (ironic since I almost never get down there to row), I have 3-4 repair projects to finish on the scooter, not to mention washing it, and I now have two ham radio projects on my plate. In addition to the amplifier, I have the ATS-4a kit which I bought in January, still sitting unbuilt. If you're reading closely, you may recall that I had posted that I bought an ATS-4b. Upon closer inspection of the kit recently, it turns out that what I have is a 4a. The seller was mistaken about it, but it's OK. The differences are very minor – the 4b seems to have a slightly better screen and an updated AGC circuit, neither of which is critical to me.

I've resolved to focus on one project at a time and try to clear this backlog of stuff, because in 4 months I'm going to become a dad, and then I suspect I will have almost NO free time! So 2 weeks ago Nick and I went to the rowing club to use the drill press there and try to do some of the metalwork needed to make progress on the amp. First I spent probably over an hour laboriously cutting a hole in the top of my steel enclosure for the amp PCB to attach through. By the time I was done I was firmly reminded of why an all-aluminum box would have been a lot better. I also managed to cut the hole slightly too wide on the ends, so the heatsink can't cover it completely. $#%#$%! It's not too big of a deal, I'll just have to cover it with some tape.

Next we marked and drilled all the holes in the heatsink, using a center punch to get us started. It would have been better to do this before assembling the amp for two reasons. First, I could have marked the holes more accurately with the PCB sitting flat on the board. Second, when finished I could have physically mounted the transistors and THEN soldered them to the board, thus ensuring that they sat flush on the heatsink. Now I'm probably going to have to rework or even remove them when I mount the board to make sure everything mates up properly.

With the holes drilled we started the process of tapping them for the 4-40 screws. I've never tapped holes before, so Nick showed me how and we did two of them, and then called it a day. I planned to do the rest on my own. There are a total of 12 holes to tap in the aluminum heatsink. I worked on the rest over a couple of evenings this past week, did two more this morning, and I have four to go. It has taken me a bit to get the hang of tapping, but I think I've got it down now. I just work the tap forward and backward a bit at a time, stop and go in reverse a few turns every now and then, and after 4-5 full turns I remove it and clean out the chips. I'm able to do a hole in about 20 minutes now I think, where it was taking me 45 when I started.

Once this is done I should be able to mount the amp to the heatsink, and then Nick and I can test it more and try to get it tuned and dialed in. After that, we'll need to integrate the LPF board and band select knob, and then whip up a keying relay.

Rob (AK6L) and I are talking about working field day together this year, possibly from the rowing club since it's right on San Francisco bay. Nick might join us as well. It would be great to have the amp in usable condition by then, but I'm not sure it's feasible given how much more work we have to do.

I've continued to try and practice morse code, focusing mostly on numbers since that's the main group of characters that I don't know well. It feels like it has gotten harder though, working with close to 40 chars. It's a real struggle to keep up and have any kind of accuracy, even at an effective speed of only 4wpm (20wpm character speed). I just need to keep practicing. Part of me feels like maybe I should just get on the air and start making CW QSOs, but I'd really have to rely on the computer to copy for me, so I'm not sure it would help me get better. Once the amp is done though, I'll want to get my ATS-4a built, and that rig can only do CW. If I can learn it, I'll be able to operate remotely from almost anywhere, with minimal accessories, and that really does appeal to me.

Once I make more physical progress on the amp I'll post some pictures!

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Pictures of the amplifier parts

Here are a few pictures of the amplifier parts I have so far.

First, the enclosure with heatsink resting on top.




The amplifier resting on the heatsink.




Amplifier by itself.




The low pass filter board.




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