Heathkit HD-1250 clean up

The Heathkit HD-1250 grid dip meter (SN 05706) I acquired at the hamfest a few months ago looked in decent condition aside from some pretty major foam rot.

Finally got around to getting it cleaned up, which turned out to be more of a mess than I anticipated. Unfortunately, the foam rot wasn’t as easy to clean up as I thought it might be.

The foam ended up disintegrating into an ugly sticky mess. I was able to brush most of it off, but it left a gluey residue on everything.

I was able to clean off the sticky goo on the coils, but unfortunately whatever it was that the foam disintegrated into also had the same effect as paint stripper. When I tried to wipe the residue off the case, the paint underneath was coming off as well.

Since it didn’t look like I was going to be able to get any of the goo off the case without taking the paint off as well, I decided to just scrape it all off. The case is in three pieces: face plate and two side pieces. Undo four screws at the bottom and one each in the front and back of the case and the case comes apart pretty easily.

The insides look in pretty good shape, aside from a leaky battery that also took the battery connector with it (easy enough to replace). A few more pieces of disintegrating foam that were originally to cushion the battery, but it was just dry and crumbly fortunately.

Scraping the goo off the face plate was easier once it was freed. Pretty much all of the paint on the top of the face plate ended up coming off. Some of the paint along the top of the side pieces where the foam stuck also had to be scraped off.

There was also a good bit of pitting in the lower part of the face plate from the goo.

Mostly cleaned up and back in the case

The HD-1250 is a little more bare, but mostly cleaned up. The labels on a couple of the coils have faded away, so there’s no indication of what frequency range they’re for. I’ll have to hunt down a manual and see if the coils are described in it. Aside from some surface corrosion on part of the RCA plug shell (easily sanded off), the coils still look in good shape. The electrical repairs and testing will have to wait for another day.

Charleston Hamfest 2019 acquisitions

This year’s hamfest notable acquisitions:

  • Yaesu FT-1802M/E 2m mobile
  • Yaesu FTM-3207D 70cm mobile
  • AADE LC meter IIB kit (unassembled)
  • Morse code bug
  • Heathkit HD-1250 grid dip meter
  • Kanga PSK interface (unassembled)
  • DZ 40m HT kit (unassembled)
  • Yeary Communications short wave crystal receiver kit (unassembled)
  • Several boxes of random items that were set on the “Free Stuff” table (I haven’t gone through these yet)
  • MITS Altair 680

Ended up spending more money that I usually do at hamfests, but quite a bit less than I could have.

I haven’t had a chance to test either of the radios yet, but they both looked pretty clean (the FT-1802 looked like it had never been taken out of the box).

The kits I picked up came from the W4RAK collection that was donated to the club. I had been wanting to get one of the AADE LC meters for a while, but unfortunately the owner died before I could pull the trigger on one. When I saw the unbuilt one in a box, I grabbed it right away. I saw the 40m HT kit, I was like “Huh, wut? What the heck? Holy crap! I need this.” A quick look at the documentation shows it’s a 40m (7.290 MHz) AM radio in a handheld form factor, rechargable (lithium ion) battery pack, but without the optional antenna/antenna matching unit). Realistically, it’s essentially a novelty item and I don’t expect to get a whole lot of use out of it. Maybe I can get it built in time for next year’s AM Rally though.

The Heathkit grid dip meter is a bit messy because of foam padding disintegration (foam rot), but otherwise looks pretty pristine. Should be pretty easy to clean up I think.

The gem of my acquisitions I think is the Altair 680. I haven’t plugged it in yet, but it seems to look in pretty good shape.

With PhD work, it will probably be a while before I get around to messing around with any of my new acquisitions.

Charleston Hamfest 2019

The 2019 edition of the Charleston Hamfest is over, and this one was an especially busy one for me. In addition to helping with set up and cleaning up, I ended up taking over the announcer/door prize giver-outer/question answerer role for the hamfest. I didn’t have quite as much time to browse the hamfest and shop, and I wasn’t able to help out in the license test session like I have in previous years. However, one of the perks of participating in the setup is that you get to see a lot of what’s being offered for sale, so that was when I ended up doing most of my shopping.

In 2018, the club received a substantial donation of equipment from a club member (W4RAK) who was downsizing due to health reasons. It took several months and many truckloads to move the equipment he donated. Sadly, W4RAK became a Silent Key around October 2018.

I don’t think I got to meet W4RAK, but I’m told he was a long time club member and that he was part of the Air Force MARS program. Based on the equipment he donated to the club I can guess that he had been a ham for a long time, was a big collector of radio gear, and liked to build things. Among the equipment donated to the club was a huge collection of Heathkit, Hallicrafters, Kenwood, Yaesu, Flex, and Elecraft radios, an abundance of power supplies, kit items (built and unbuilt), and other vintage equipment.

A fair bit of the donated equipment is going to be set up in the CARS club room for operating and display. A much larger chunk of the equipment was put up for sale at the hamfest and priced to sell (both to get the gear back into the hands of hams who would/could use it, and so that club didn’t have to store it).

A "small" selection of the W4RAK collection sold at the 2019 Charleston Hamfest
A “small” selection of the W4RAK collection sold at the 2019 Charleston Hamfest

For anyone into vintage rigs, it was like being in a candy store. I was able to acquire a few pieces that I’m looking forward to playing with.

KM4HXA showing off his home brew antenna collection
KM4HXA showing off his home brew antenna collection

New at this year’s hamfest was a Go Box exhibit/competition, a suggestion by KN4EXJ. People were invited to bring their Go boxes to the hamfest to show off to others. For an inaugural event, there were a few Go Boxes on display. KN4EXJ had a few of his that were pretty impressive.

Looking forward to having the Go Box exhibition again next year. Maybe I’ll have one of my own to enter into the exhibition.

Winter Field Day 2019

Participated in my first Winter Field Day this weekend with WA4USN (also the first one for the club), 1O SC. The event made for a good excuse to check out the HF capabilities of the CARS communications trailer (which I suppose is the whole point of Field Day). It’s a much more casual and far less involved day than Summer Field Day (no food, fewer operators, no overnight shift).

Started off Saturday (January 26) getting the trailer set up. By the time I got to the site, the trailer had already been pulled out of the building and the radios were getting set up. Apparently there was supposed to be an HF dipole in the trailer, but it couldn’t be found so we went with the Tarheel antenna that had been mounted to the roof of the trailer.

The Tarheel is an OK mobile antenna but for long distance HF, we found our signal just wasn’t getting out very well. We managed about a dozen contacts over the three hours or so that we were out.

The next day (January 27), I brought out my ZS6BKW antenna. By the time I got there, the others had already set up the trailer with a 20 m dipole hanging on the trailer’s pneumatic mast. We switched out the 20m dipole for my antenna and got back on the air.

The dipoles worked much better than the Tarheel, and with the ZS6BKW, we were able to operate on 40 m and 20 m.

Weather was fairly decent (especially compared to other sites further north). Sunday was a good bit colder than Saturday was though, and I was starting to get a bit on the stiff side by the time we wrapped things up.

Ended up the event with 69 contacts on 40 m and 20 m, mostly phone but a few digital (PSK) in there as well. It was a good exercise for myself and everybody else who came out on getting the trailer set up and operating from it.

I also think I want a pneumatic mast for the house like the one on the trailer.

Antenna and filter books

Two new additions to the library arrived in the mail this week thanks to the 2018 ARRL auction.

In this year’s auction, I managed to score a copy of Antenna Theory: Analysis and Design 2nd ed by Constantine Balanis, and Rapid Practical Designs of Active Filters by DE Johnson and JL Hilburn.

Both books are in pretty good condition, especially the Filter book considering that it was published in 1975.  The Antenna Theory textbook still has the 3.5″ disk in the back unopened.

I was hoping to get at least one of the Vibroplex bugs that were also in the auction, but a flurry of last minute bidding drove the price higher than I wanted to pay for them.  Oh well.

Happy with the books I managed to get though.  They’ll be good additions to the library.