Vintage tube audio? Old Heathkits were everywhere, mostly low powered mono units. Quite a few Fishers and Scotts. And another table that ran the whole spectrum from tiny old amps to to big stuff and little speakers to those thunder cabinets back by the fence.
Attachments
Tubes? I bought over a hundred tubes today. Most were $1, about 3 were $2 and some were 50 cents each.
The plastic tubs full of NOS tubes were 50 cents each. I got a bunch.
These tubes were a dollar, I bought several. There were plenty of tubes for $1 vendors.
This tube was cool, but I didn't get ther price.
The plastic tubs full of NOS tubes were 50 cents each. I got a bunch.
These tubes were a dollar, I bought several. There were plenty of tubes for $1 vendors.
This tube was cool, but I didn't get ther price.
Attachments
Ditto on the $1/lb photo. There's a Tek 453 parts unit there in the foreground I'd a bought in a heart beat just to keep mine going for the rest of my life. Also an HP signal generator on the right side sitting there. Easy circuit to fix, fine unit. Don't know if that's the RF or the AF unit.
No TV7's in the buck a pound stack. Shoot!
No TV7's in the buck a pound stack. Shoot!
I've never seen a deal quite like that one but one very close.
At the DeAnza College summer flea market I found a box of about 30ea 7.5kV 35uf modern caps for $3 apiece. About 10" high by 2.5" x 1.25" oval. Like a fool I bought 3. I later sold two at $120 ea on Eflea. I bought them for an 813/813 AM transmitter project that I abandoned when I found a Gates Broadcast transmitter for $250. I wish I had them now. They were for military radar installations.
There have been discussions of building a big P-P amp going on since before I joined this forum. I got interested when I got the 400 watt OPT's cheap. But what to use for the output tubes. I was leaning toward the 6LW6 since they are the bigest and baddest sweep tube made, but other sweep tubes were considered.
Today I came across a guy who had a lot of NIB Sylvania 35LR6's. He wanted $10 each, and I offered $1. After a while I got all 45 tubes for $3 each. I would call that a deal!
I spent the day collecting RF parts, tubes, and even a SDR receiver to play with. About 3PM I decided to start the long drive home. I made it to north Georgia. 700 more miles tomorrow. Then maybe a few more pictures.
Neither one of those tubes is listed in Franks. Kinda surprising actually. I forget what's in my Drake TR-3s. It's got a j in it somewhere. Anyway I laid in a supply when I got the radios and they weren't 3 bucks apiece nor were they $10 bucks. And that was back in the 90's.
Sounds like a good deal.
But
What in the heck can anyone do with an amp that big?? I suppose a Sound Contractor could use the 70 volt line (what do you think, 1/0 big enough for the voltage drop) and then string together a bunch of boxes built with Pyle drivers? Still, your signature does say a lot. No problem blowing up any currently available speaker. Great big electrostatics, like 200 feet high and run them without output transformers.
Sounds like a good deal.
But
What in the heck can anyone do with an amp that big?? I suppose a Sound Contractor could use the 70 volt line (what do you think, 1/0 big enough for the voltage drop) and then string together a bunch of boxes built with Pyle drivers? Still, your signature does say a lot. No problem blowing up any currently available speaker. Great big electrostatics, like 200 feet high and run them without output transformers.
12JB6A.
17JB6A also works fine, and are what I have in my TR-3.
12GJ5A and 17GJ5A also work fine.
Win W5JAG
There are 3 HP audio generators sitting on the ground on the right side. I parted out about 20 of these a few years ago. I didn't look to see if they were 200AB's or 200CD's. The 200AB uses a 5AR4 rectifier and the OE tube was a Bugle Boy. The output tubes are 6K6's. The power transformer had enough juice to run a 35 watt guitar amp or a Simple SE with a B+ of 400 volts. The 200CD uses SS rectification and 6CW5's for output tubes. That's why I have dozens of 6CW5's. I took the picture from a distance. I stayed out of the booth so that I was able to "just say no."
I never noticed that the 6LR6 wasn't there. It is in the RCA RC-30 tube manual. Paper copies are for sale at AES, PDF can be found on the web, and I think at Petes site.
I find any big sweep tube worthy of respect. The 6LW6 is the biggest around, and I bought them by the dozen for $5 to $8 on Ebay until the 180 watt amp article appeared in Glass Audio, then the prices took off. I got a few well used 6LR6's from Ebay for cheap about a year ago. I managed to extract serious power from them in Petes magical red board. When I found 45 of the same sweep tube for the right price, you know I had to have them. Many glowing experiments will follow. First off, back to the red board. If I wire both channels in parallel through a common OPT, how much power can I get?
I was at the hamfest for a total of 17 hours. I spent about 14 of those hours in the flea market, where I spent far too much money. I met a couple who come here from Japan for the hamfest circuit every year. They bring tons of prime quality Japanese capacitors to sell, and buy vintage US tubes to take home. I bought over 500 NIB capacitors. They were the missing link in the Simple P-P parts kits.
This brings me to another subject. Some of my board builders have reported difficulty obtaining parts. I know that I can't get get some IC's at work even with Motorola's buying power. I know people who have had the Flex 1500 on order for over a year, Why haven't they been delivered. The DZ kit HF transceiver is in short supply too. Why? Same answer. If you aren't buying millions, you can't get parts. With the economic downturn a while back, many component manufacturers cut back or halted production. Some wafer fabs were shut down. There were plenty of parts in the distribution pipeline. Now that the big guys are building products again, the parts pipeline has been sucked dry. Simple op-amps are now on allocation. 26 week lead times are quoted for some items. Look out for the Chinese counterfitters to crank up the bogus parts supplies.
That was the biggest dissapointment of the whole hamfest. Only two projects. I took pictures, but Nikon seems to have eaten them. There 6 photos missing from the SD card. I took 6 pictures inside the main show area. Two from the homebrew corner. The camera shut off as I took the last one. Bye Bye pictures.
It has been said that you can see everything at a hamfest. Here are three pictures showing things that are not expected. Not everyone is here to talk about radio equipment. I must say that despite the weather people promissing rain, this was my first trip to Dayton where I didn't get wet, unless you count sweat. Yes it was hot, in the 80's, yet this guy was walking around in a NASA suit without benefit of active cooling. Note all the Zeniths in the background. Some people make music instead of talk. The guy facing the other way is playing a mandolin. Some people buy a swap space to show off their homebrew projects. In this case a solar powered Prius.
Attachments
Thanks Win. I copied that to my documents just in case. Lot's of folks don't know that a TR-3 will put 240 watts up the pipe with a fresh set of tubes and carefull tuning. I used to run double sideband once in awhile too.
Dan
