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  #1  
Old 11-30-2013, 10:06 AM
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N2IXK N2IXK is offline
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Oscilloscope score at local Ham Radio auction--Tektronix 7904 w/ 4 plugins--$15!

Sold a bunch of junk at my local radio club auction last night, and ALMOST made it out the door without buying anything. But then this guy went on the block, described as "not working" with no takers at a starting bid of $20. I really didn't NEED a 4th oscilloscope in my already cramped home lab, but when the price got dropped down to $15, I figured it would be good for parts and scrap aluminum if nothing else, so it ended up following me home.

Turns out, all the thing needed was to pull and reseat the plugins, and it came to life. Even the calibration seems pretty good. This is a 500 MHz mainframe, which came with 2 7A26 dual trace vertical amps, and 7B85 and 7B80 timebases. As configured, it is a 4 channel, 200 MHz scope, with the capability to display 2 different timebases at the same time. With a spectrum analyzer plugin, you could have both a time domain and frequency domain display on the screen at the same time. Property tags indicate that it was surplussed out of CBS-TV central engineering lab.

Pretty dirty inside, but a brush and shop-vac should take care of that. One busted knob, that I should have a replacement for somewhere. A shot of deoxit on a few dirty pots and switches, and I think I have a keeper. Certainly the most capable scope I have ever owned, and wretched overkill for most of the work I do at home.
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  #2  
Old 11-30-2013, 10:15 AM
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You Lucky Dawg... That Bad Boi was Tek's TOTL scope back in the day, I think...
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  #3  
Old 11-30-2013, 10:59 AM
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That is very cool ! ! I would have a hard time walking away from it for $15. or even $20.

Now that you have it I'm sure you will Find something to use it on....

Hint Hint I'm still looking for a working time machine....

I bet you could use that to start building me one....
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Old 11-30-2013, 11:06 AM
snelson903 snelson903 is offline
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man thats a great score , wish we had ham fest or radio shows around here ,all they care about is strip malls , nort-dame football ,or some kind sport ,and bars.
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Old 11-30-2013, 02:16 PM
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I went to a "Ham-Fest" in Knoxville about 15-20 yrs ago. It was in June in a STIFLING high-school gym, & about all that was there were computer geeks, & 440 MhZ stuff- Those little things you can put in a shirt pocket. Precious little "Real" radio stuff, but one guy had a rather forlorn lookin' Hallicrafters of some type that he was touting as being "Bill Halligan's PERSONAL set..." Oh, & some guy had raided a "Hidey-Hole" at UT or Oak Ridge, & loaded up all the junky 5 MhZ toob-type scopes he could put in his pickem-up..You MIGHT have managed to make a couple of half-way decent scopes out of the whole mess, if you were lucky..
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Old 11-30-2013, 02:48 PM
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Hamfests have certainly declined in the ~30 years that I have been going to them.

The computer junk, car audio, and plain old consumer electronics garbage far outnumbers (and outsells!) the ham radio and test equipment that was once the mainstay of these events. Vintage ham gear went from being "boatanchors" that were priced by the pound to "rare" collectibles going for top dollar on eBay. The decline in US manufacturing and research caused the surplus test equipment pipeline to dry up or become so special-purpose and exotic that the average hobbyist has no need for it. And the audiophools sucked up all the good NOS tubes, and raped the remaining vintage test gear for the transformers and tubes.
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Old 11-30-2013, 02:53 PM
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Nice to see a good deal is still to be had out there!

Just about all my test equipment I accumulated 10-20 years ago at ham fests and sidewalk sales. Used to go to one almost every weekend often before the crack of dawn to find those golden nuggets out there.
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