wolke — Alan – Page 3 – SolderSmoke Daily News

Tek Troubleshooting Triumph

Thanks to the manual provided by Jim and the HV test gear provided by Alan Wolke, I was able to finish the troubleshoot on the broken Tek 465. It is the HV multiplier, U1432. The cathode voltage is supposed to be -2450. It initially tested at -1000. The manual calls for a jumper to be removed to take the HV Multiplier out of the circuit. As soon as I did that, the cathode voltage went to -2500. Bingo.

Now I have to get a replacement for U1432. Any carcasses laying around?

Thanks guys.

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Inside a Tek 465

The TEK 465 ‘scope is as they’d say back in the Bronx “a piece of work.” It has real character. Perhaps a bit too much. If you look closely, you’ll see transistors in sockets. I had kind of gotten my head around that, when I noticed that many of the transistors were not in sockets. They looked like they had been soldered to into the holes in the PC boards. But NOOOOO! They are snugly in the holes, but they are NOT soldered in! You can pull them out, then (if you are lucky!) slide them back in. There is even quite a bit of “ugly construction.” with connections floating in the air. You can really see the influence of tube era thinking in this instrument.

I think I have narrowed the problem down to the HV supply. Alan Wolke is lending me a high voltage probe. I hope to be able to get it fixed this weekend. I need to get it working because my BITX 17 is nearing completion and I’ll need the ‘scope for the lineup and de-bugging.

The picture above is from: http://www.eevblog.com/forum/projects/tektronix-465-repair-and-restoration/ More pictures of the scope are available there. Also see http://www.spurtikus.de/basteln/repair/tek465/index.html for more scenic views of this instrument.

Fixing TEK 465 Oscilloscopes

I’m having TeKnical difficulties. My beloved Tek 465 ‘scope quit on me. I’d been running it continuously for a day or so, watching the output on my BITX VFO. Then, suddenly, it blew the 1.5 amp fuse. I replaced the fuse, but afterwards the trace was gone and the “Low Line” light was acting weird — on when it should have been off, then flickering. I consulted with Alan Wolke. He happened to be out at TEX HQ in Beaverton, Ore. He provided some good suggestions, but before I had a chance to try them, the trace came back. I attributed this good luck to the Radio Gods being pleased with Alan’s presence in Beaverton… but my reprieve was short-lived. Trace went out again today.

I found this video of the legendary Jim Williams (RIP) fixing a Tek 465. (Check out Jim’s junk box!)
I’ll start by checking the Tantalums. I may get lucky.

If anyone has any other suggestions, send them this way. The Tek scope may be old, but it is a COMPLICATED piece of gear…

Three Great Videos from Alan W2AEW

Bill:

While not really homebrew, they do deal with QRP and RF. The first two are walk-throughs of the schematics of two QRP transceivers, and the last is a discussion of how diodes can be used as RF switches. I thought you’d find them interesting.

MFJ-9340 QRP Cub CW Transceiver kit schematic review:

http://www.youtube.com/watch?v=2QSwXv2RJzw

Heathkit HW-9 schematic walk-through:

http://www.youtube.com/watch?v=rPM1vvGorTo

Using diodes as RF switches:

https://www.youtube.com/watch?v=YBNIq_d56sA

73,

Alan
Http://www.youtube.com/w2aew

Vintage Tektronix Museum

The radio gods seem to have been guiding me to this web site. Last night I was listening to 17 meter phone and I heard a station calling TEK guru Alan, W2AEW. I couldn’t hear Alan (skip zone and all that) but just hearing his call turned my thoughts to Beaverton, Oregon. This morning I found a message from Dino, KL0S, alerting me to the VintageTEK museum. FB! Analog Rocks On!

http://www.vintagetek.org/

Alan Sends Video Through HIs ‘Scope

Who needs plasma screens! Real hams get their video on the screens of Tektronix oscilloscopes!

Good one Alan! Glad to see that you made it onto Hack-a-Day with this one!