Sunday, July 12, 2009

INDY HAMFEST

I arrived about 0730, which is a wonder for me, and promptly found myself at the end of a long line of vehicles waiting to get in. We all moved along quite smartly, though, and I was being guided to a place in the squishy, unpaved field in a few minutes. Remembering the weather forecast, I had my doubts about getting back out but then again, we're talking several hundred radio amateurs: about one auto in four was some sort of a truck and the younger guys are just about always ready to lend a hand. (This proved to be half a prophecy, or perhaps two-thirds, but that's another story).

There isn't any real high ground at Camp Sertoma so you'll have to take my word that there was a good crowd and a goodly number of tables, in four rows about a city block long each, generally down both sides. I passed up a Ten-Tech OMNI-D, alleged to be in working condition and priced to move at $325. Not tube-type but a fine example of solid engineering.
"Solid engineering" is all around at these gatherings -- here's a VFO, a pair of power supplies and a slow old oscilloscope. (I'll tell you a secret about those "slow old scopes:" If the HV power supply is working, you can get right to the deflection plates in 'em, bypassing the tube amplifiers that are the slow part. A visible fraction of an inch per volt is typical sensitivity and with a proper DC-isolation condenser in series, they will let you look at very high frequencies. There are limits to this trick and it is deadly dangerous if you don't know what you're doing! Most of them will also do an "X-Y" display without any modification, quite interesting with the Left and Right channels of a stereo signal hooked to the inputs).

Speaking of audio, need a microphone? The front rank is the still-ubiquitous Astatic D-104 crystal microphone, a nice-sounding (communications-grade) device that was built from 1933 through 2001. (More D-104 info here). Closest in the front rank is (I think) a Shure "Green Bullet" mic popular with harmonica players for its overload characteristics. Or possibly a relative.

The seller also had some nice Heathkit items -- I was tempted by the "universal" tube rig power supply (HP-23) just edging into the snapshot at the right but left it for a Heathkit collector to find. Power supply parts are still pretty well available, thanks in part to the guitar amp and tube high-fidelity folks who keep demand for new parts high.

I saw something on the third table that I looked at that the seller dropped the price on as soon as I expressed interest. I paid for and left it there (hey, he looked honest!), as it was a little heavy and awkward. We'll get back to that.

This HQ-140XA called out to me. I don't own any Hammarlunds and though I'd prefer something even older, they kept the same basic layout all along. The price was right but I decided to see the rest of the flea market before deciding. Interesting National transceiver next to it -- that's an NCX-5, I believe, and he had an NCX-3 next to it. They are said to run to hangar queenliness and are not very common; by the time they were introduced, Collins had captured the high-end market and held it right up until they stopped making amateur radio equipment. As a result, Collins gear is a lot more common, commands higher prices, and enjoys a higher level of support within the hobby.

Like any other tables-for-rent venue (collector-car meet, gun show, etc.), not every seller is entirely focused; this one does have a nice assortment of threaded fasteners but also offers gum boots, some sort of instrument keyboard, mounted and unmounted animal skulls, soft-sided luggage and Star Wars memorabilia. Um, okay. Is that a Jackelope?
And there's always one or two how-did-it-get-here? items, like this device.

I know what it is and what it does; it appears to be complete and the price is way more than right. I'd kind of like to have it for work. What I don't know is where it came from, if the less-obvious parts of it are actually functioning and -- on a Saturday -- if Andrew still supports this model. (It's a compressor/dehydrator with nifty rate-of-flow controls and metering on the output, used to keep high-power RF transmission lines -- rigid coaxial line and waveguide -- dry. This is important, as they tend to arc over and burn if they get damp inside.

Could I get reimbursed if I bought it and it needed expensive repair? Could I carry it to my car unassisted? Probably not and oh, holy heck no. Kind of a nifty gadget to look at, though.

Anent nifty gadgets, I went to the air-conditioned building and before I took the upgrade exam on impulse, I saw these:
The one on the left is a semiautomatic key about one-quarter the size of the typical Standard Vibroplex and possibly as much as three-quarters the size of the tiny, rare Vibroplex "Midget." It functions perfectly; shut your eyes and your fingers think it's a very good example of one of the big keys. On the right, an all-mechanical, fully automatic key, meaning it makes dits and DAHs as long as you hold the lever in the proper direction (not forever, it's mechanical and you're the sole source of power!), about two-thirds the size of any other examples of this very rare type of key. The fellow who makes them lives here in Indianapolis and every year, he has a few new ones to show. His work is simply amazing, generally eschewing springs in favor of magnetic repulsion and using innovative bearing designs.

What did I buy that was heavy and awkward? Something inherently dangerous! And esthetically pleasing, at least to me:
Yes, it's an antique fan and no, it doesn't work. You can see the cap over one of the brushes at the right and the wire leading from it back into the motor housing. The wire from the motor housing to the base is missing, as is the cord and plug. In the base, a nifty switch with open contacts; the little tab that sticks out is on the "live" switch arm. though the tab itself is Bakelite and probably perfectly okay with everyone except the good folks at Underwriter's Labs -- just don't stick your little fingers in the slot it works in, as the hot stuff is right inside! Then there's the mostly-notional protective grille... The universal-wound motor is probably rebuildable and I am tempted to see if the local motor shop will look it over and try fixing the motor. The base, grille and blades can be cleaned up and painted -- I'd like to re-Japan the base but it's tricky to get right and a good sanding followed by gloss enamel is temptingly simple. The oscillatory drive does still work as the motor shaft is turned and the bearings don't have much play. How cool is that?

The other items I bought will be covered in a later post. Stay tuned!

9 comments:

  1. Looks like we share some interests in weird old stuff... except it appears that you actually know what you're doing :)

    http://tinyurl.com/lyqwna

    http://tinyurl.com/lt2yee

    I think I'm gonna like looking around here. Found you via Brigid's page, btw.

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  2. Looks like you had a good time!

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  3. Welcome!

    ...As for "knowing what I am doing," it appears to me that your project *worked* and that's the only test that counts.

    Physicist Richard Feynman ended up as the the de facto locksmith at Los Alamos; he didn't start out knowing any more about it than anyone else but he had an engineer's eye and picked it up quickly, all the while certain that a real locksmith would have a far more sophisticated bag of tricks. After the war, he ended up elsewhere but chanced to visit Los Alamos one day not too many months later and when he heard they had a real locksmith, went to chat with him, thinking he might learn a few things. He didn't introduce himself beyond his first name. They had a nice conversation but when it turned to handling difficult locks, the locksmith sighed and told him, "I like to think I'm pretty good but you really should have stopped by when that Feynman guy was working here -- he was a real wizard!"

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  4. Cool! Brigid tipped me off to your 'new' blog.
    73, Jim KQ6EA

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  5. I love your other blogs and I love THIS blog, but does anyone else see the irony of posting a retro-technology blog on the internet?

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  6. I tried mailing it to people but that took too much time and money. Perhaps I can find a nice letterpress and try again -- but the photos wouldn't be color. :)

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  7. I had a floor fan similar to that many years ago, with the same shroud which would not be of much use to anyone.

    The sweet deal is to have the shroud galvanized and the blades cadmium plated. Not as difficult to get done as you'd imagine. And the brushes are easy to find or make. The tough bit is the commutator and the worm drive for the oscillation engine. If those are gone or beyond repair you're hosed. Make it work, No. 1!

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  8. Glad I found your new blog! I know nothing about HAM but I'd love to tag along to the next swap meet because I need more random stuff.

    Oh, if you're ever in Portland, OR, go to a store called "Really Good Stuff". It's the coolest antique and oddity store ever.

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  9. If I am, I will, Red!

    ...You're entirely welcome to come along to the next Indy Hamfest. Hamfests in general are good sources of interesting and, yes, kind of random stuff!

    (I'm glad you found my new blog, too).

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