985 Workbench: 2024-08-12

My Week in Radio

  • Watching APRS
    • trying different radios/antennas w/ aprsdroid
    • slim-jim working better with any radio
    • watching logs and better-understanding the structure of the packets
  • N3TWT repeater (South Mountain) looks good for “off grid” communication when camping in Cumberland county
    • heard lots of volunteer event activity
    • also heard N3FYI & N3KZ
  • moving in September, so scheming new antennas
  • maybe noticing a bug on AUBS firmware on Quansheng. I have copy of code to read and see about a fix.
  • I tried another firmware, but missing the killer feature: scan on start

Notes from Others

  • Everyone went to Kimberton Hamfest
  • AF3Z, Jim: wait 30 years, and that shiny new radio will be affordable.

Questions

  • W3JAM, Jeff:
    • using a generator, how important is ground?
      • KC3RFG, Jim:
        • already grounded if connected to home.
        • job site may require a ground rod, but doesn’t do much.
        • for field day, generator is the only “reference”, so no need for ground
        • modern generators have GFI built-in.
      • NA3CW, Chuck:
        • don’t let generator run down and stop under load, because it’ll degauss the residual magnetism
    • Heathkit SB102 w/ 6146B tubes. It wouldn’t tune up. is there concern with using 6146W tubes?
      • NA3CW, Chuck: 6146W is the ruggedized version. it should work. neutralize, and you’re good to go.
      • AF3Z, Jim: be sure to check the tubes with a tube-tester
  • AF3Z, Jim:
    • cable management while being able to access and change. beat the rats’ nest. Are there good systems for cable management?
      • WA3VEE, Ron:
        • best if you can walk behind the desk
        • everything slides on felt feet, so must have some slack loosely coiled.
      • NA3CW, Chuck:
        • desk 90 degrees to the wall for easy access to the back.
        • garden velcro: can be snipped to any length you need.
      • KC3JAM, Jeff:
        • military systems require being able to get behind things.
  • KC3OOK, Bill:
    • Has anyone used DragonOS / Linux?
      • NA3CW, Chuck: Mint, but not Dragon OS.

985 Workbench: 2024-08-05

My Week in Radio

  • Mobile APRS is proving to be really short-range
    • Couldn’t even spot myself outside at Sam Lewis up on the hill
    • Cycled with it, but no traffic
    • Needs a real antenna
  • Some POTA
    • Sam Lewis, US-1418
      • found the leading park activator, kn3a, in my spot. :)
      • storms rolling in, so called it quits
      • watched 20m slam shut: decoding 30 signals to 4
    • Susquehanna River, US-4567
      • Columbia Riverfront Park that’s open after sunset
      • spanned into the next day…again, so had an incomplete and a complete activation.
  • Got an FT8 contact to Israel with 5W from home: first Asia for me.
  • Weekly RTTY Test and FT4 sprint
  • Ham radio software may not be the most efficient
    • fldigi left running but disconnected from radio ran CPU at 95C doing nothing.
    • GridTracker likes to burn cpu too when left running.
  • AB3AP, Mike, on EZ-Hang slingshot: I’ve given up the slingshot and just swing my throw line by hand.
  • KB3ILS, Keith: there are scripts online for 3d-modeling any size knob you need.

Questions

  • W3JAM, Jeff:
    • Does anyone have experience using Drake TR4CW on AM?
    • Can you add a noise blanker to this radio?
      • Noise blanker would alleviate pulsing noise from electric fence.
      • Jeff will be getting the entire manual library on CD, which will have information.
  • KC3OOK, Bill:
    • How do you connect a NanoVNA to an open wire feed line?
    • WA3VEE: Would you need a balun to start getting close to impedance to match the expected 50 ohm?
    • W3JAM: Doesn’t matter so much where it’s tuned, since you use it with a tuner anyway.
    • NA3CW:
      • You don’t want it to be resonant anyway, because being resonant will give you the largest extremes to tune when trying to move to other bands.
      • NanoVNA may be limited on the impedance it can read.
      • Dipole should be at least as long as half wave + a little
      • He extended a wire to get it to tune where it wouldn’t.
  • WA3VEE, Ron:
    • SOCO connectors carry 208V. When rewiring those connectors, what’s a good caulk-like sealant that could be used for “potting” the inside of the plugs?
      • Plain bathroom caulk can be conductive.
      • Silicon may breakdown at lower voltage than needed too.

POTA US-4567

Ben and I grabbed dinner and headed to the Columbia Riverfront Park to activate US-4567, Capt John Smith Trail.

Since there were more people around, I setup the simple GRA-1900T next to our picnic table instead of throwing wires. 20m was very busy, so I was getting a bit lost in all the traffic. I moved to 40m and re-tuned to rack up my more local contacts. As the sun set, our reach got better on 40m. Of course, I accidentally crossed 0000UTC again into the next day, so it was 2 activations: one (incomplete) with 5 QSOs, and the other with 14 QSOs. I operated all digital, since it got dark, and we were looking to pack up soon.

pota  us-4567  hf 

POTA US-1418

I headed back to US-1418, Sam Lewis to tried a quick activation on my way to my parents’ house, but I got sidetracked. KN3A, Scott, was already there, so I chatted with him for a few minutes, and then setup my station on the other side of the park. I used my GRA-1900T for a quick setup on 20m. I saw Scott hunting up the band with his big, very local, signal, and then set out to do some FT8. The band was busy, but then just shut off nearing 1900UTC.

I heard about a storm coming from the local repeaters. I tried a bit on 15m, but decided to pack up as I heard more thunder. I only got a few contacts, since I didn’t give myself near enough time.

pota  hf  us-1418 

985 Workbench: 2024-07-29

My Week in Radio

  • During last workbench, I used the TYT HT in crossband for the whole net. It gets hot but works.
  • I found a bug in the Aubs firmware on my Quansheng radios. It skipped lots of my repeaters for a day.
  • Trying the TIDRadio TD-H8 tonight on M/5W power with the good old tape measure Yagi. It’s sounding really nice here.
  • On linux, I found cwcp for CW training. I run it at 20wpm with a very slow 20-dot gap.
  • I’ve been trying APRS with QRZ-1, an 8-year-old Nexus phone, and a btech APRS cable.
  • POTA in York:
    • I had a terrible time throwing into trees that were too high.
    • Resorted to an inverted-V EFHW, 2ft-10ft off the ground with telescoping fishing pole.

Questions

  • KB3ILS, Keith
    • How does a hack learn to read basic schematics: conventional or electron current flow?
    • Tips for reading schematics?
    • Chuck, NA3CW
      • Except when dealing with tubes, work in conventional current.
      • Diode and transistor arrows show positive to negative (conventional) flow.
      • Inside tubes the electron flow is shown negative to positive.
      • Reading schematics:
        • Look up different circuit functions
          • Amplifier
          • Audio oscillator
          • etc
        • recognize those groupings as a “block diagram”.
        • learn to read like a block of functions
        • trace with your finger
    • WA3VEE, Ron
      • Think of circuit groups as mechanical operations.
  • KC3YIG, Dave
    • Recommendations for distributing power to multiple radios?
    • Astron powering 2 kenwoods: 25w and 65w, 2m and HF base stations.
    • W3QP, Tim
      • Ham Radio Workbench has a nice power distribution block as a kit:
        • 1 anderson power polse for input
        • 5 anderson power poles for output
    • WA3VEE, Ron
      • PowerWorx gear for power poles
    • KC3NZT, Harvey:
      • Anderson power pole has become standard in ham radio.
  • KC3NZT, Harvey
    • Operating internationally, in Canada, do we just add “/ve3” to call?
    • W3QP, Tim
      • That’s right for Canada, as long as you’re there temporarily, up to 180 days or so.

Upcoming Hamfest

Reading Radio Club will host their hamfest in Sinking Springs.

985  workbench  net 

US-1418

At Sam Lewis, US-1418 I tried setting up down near the low playground on the corner near the road. There were no trees with good spots. All the viable branches were very high, and I couldn’t quite get a line over them.

I resorted to an inverted-v supported by fishing pole in the middle at 9ft or so. I operated mostly FT8 on 15m, 20m, and 40m, and I did a little SSB on 40m. I got Canada, Florida, Illinois, Missouri, Kansas, etc.

pota  hf  us-1418 

Bug Scanning on Aubs 00.07

I have my UV-K5 and UV-K6 running aubs 00.07 firmware. I added a simplex frequency (446.100MHz) to use as with my local cross-band repeater in position 110. I added the new channel to scan list 1.

Upon powering on the radio, I could scan lists 1 (local repeaters) and 4 (satellites) together. When I press the up arrow to advance off an active channel, the scan would now skip list 1, and go right to 4, and continue to skip list 1. Before I realized it was happening, I thought the day was super quiet.

I dropping the repeater frequency from scan list 1, and the scanning behaved correctly. I tried removing another channel from scan list 1, and reintroducing channel 110 to the list, but that didn’t fix it, so it’s not an issue with the count.

Much of scan list 1 is lower in the channels, so I moved my new repeater frequency from channel 110 to position 30, right after all my other simplex channels. That seems to work fine, so that’s how I’m leaving it.

I may need to try some more things and figure out a reproduction to file a bug on the project:

  • Is it something about the frequency of 460.100?
  • Or is channel 110 the problem?
  • Would another frequency in that spot be a problem?
  • Are there other channels that would trigger the issue?

SPARC Meeting: 2024-07-23

At the previous week’s meeting, many people built EFHW kits and untangled some wire to use with them. No one finished the build and brought them back, so I offered a quick demo of tuning such an antenna.

I connected my 49:1 unun that I’ve been using to a new wire we had hanging. We connected a handful of different analyzers to see how they operated.

sparc  club  efhw 

985 Workbench: 2024-07-22

My Week in Radio

  • Great to see everyone at the breakfast, especially Luke’s loose couplers.
  • POTA after the breakfast at Marsh Creek with Vic, KC3TYX
    • 20m was the place to be, but 2 of us operating, so we had to take shifts with our own radios.
  • Prime Day Shopping
    • microcord
    • TYT HT for 10w crossband repeater
      • I’m using it now as the repeater
      • Less tethered to the outside antenna
      • Top of the radio/sma is 50C after repeating for an hour on power
    • TinySA
    • Raspberry Pi Zero W kits
  • APRSDroid: phone & radio
    • email gateway
    • POTA spotting

Notes from Others

  • solarham.com
  • Reading Ham Fest coming up
  • VE session at Stateline Radio Club

Questions

  • KC3WWC: What’s cool about APRS?
    • APRS weather station
    • PWS monitor app to find weather stations near me
    • Other gateway frequencies?
    • Check with CCAR/ARES/RACES nets for their uses.
  • KC3WWC: In Galenium detector, how does one know when the cat whisker is right?
    • Joe, W3GMS
      • put on headphones
      • move spring arm with stiff wire (cat whisker)
      • touch it to the galenium
      • move around to find the hot spot where it’s louder
      • germanium diode conducts at very low voltages, so easy
      • loose couplers don’t work so well in a crystal set, since it’s lossy
      • spark era - 1913
      • before galenium, there was a tube with metal filings, a “coherer”.
        • activate a buzzer
        • tap that would fall and reset the coherer
      • after galenium, then audion tube
      • imperative to have a very big antenna to capture as much signal as possible.
      • drive diode into forward current
      • Heathkit made a collectible kit
        • tightly coupled
        • voltage increase in the second coil
        • higher Q, so could be made more selective
      • Luke, KC3SCY, counted 20 different stations one night
    • Chuck, NA3CW
      • fox-hole radio: rusty razor blade, lead pencil, coil, safety pin, oatmeal box, wire
      • galena: ore of lead sulfide
      • immerse the galena in base of lead solder
      • grope around quietly to find magic spot where it works best
      • same thing with foxhole radio
      • uses oxide for detecting, not stainless
      • galena has 0.4V drop, like germanium diode
    • Ron, WA3VEE
      • has a marconi cat whiskey receiver
      • 0.4V can be converted to dBm, and it’s a pretty large signal required
      • predates any amplification
  • WA3VEE: What is the most important measure of solar activity we need to consider?
    • most profound affect on propagation?
    • KC3RFP: a-index (9 or lower) k-index (5 or lower)
    • Tamitha Skov website and youtube

985 Breakfast and POTA

985 Breakfast

It was good to chat radio with everyone, and Luke talked about restoring his antique loose coupler radio.

US-1380 Marsh Creek

After breakfast, Vic KC3TYX, and I made our way to US-1380 Marsh Creek for a park activation and to compare notes on how we operate.

The weather was pleasant, and Vic started on 20m with a vertical ham stick and faraday cloth for a ground plane.

I tossed a EFHW to slope from the picnic table up into a tree. I got it in a good spot with the first try. I was on 40m to give him some room, but the band was pretty dead in the middle of the day. I still had a little interference, since Vic was running 100W. I eventually switched to 20m when Vic had enough contacts, so I could finish my activation. Only 15m and 20m really worked for much. I did all digital + 1 phone to another park in Tennessee.