Less what I bought today and more what I bought approx 10 years ago and let gather dust ever since
. A basket case of a Tek 536 scope that I paid AU$70 (USD$50) for with CA, T, G and B plugins. Today that would be a good deal just for the tubes alone.
Looked like it had sat for decades in someones moist garage gathering rust and dust, then someone tried to turn it on resulting in a carbon tracking extravaganza in most of the powersupply circuits
. It's also very high hours, or someone robbed it for tubes at some point and someone else restuffed it as the tubes are of all sorts - Aussie, American, British, European.
After cleaning, grinding away all carbon tracking on the ceramic strips, cleaning relay contacts, rebuilding the fan, replacement of all electrolytics (all leaking >1mA after 30 mins on my cap tester so out they go), replacement of a couple of cooked 6080 tubes and some burnt resistors I got to the point of plugging it in to my dim bulb tester (with 700W of bulbs including the heat lamps out of my bathroom
) and pleasingly it didn't turn into a giant carbon arc. Running it straight off mains the 'low voltage' supplies (-150, +100, +225, +350V) are solid. The type CA plugin just rails the vertical amplifier for some reason (maybe just needs a cal?) and the CRT powersupply is weak and gets continually weaker as it runs until the trace disappears completely (-800V rail starts strong and quickly droops to -400V, then I cut the power as I don't want to fry anything unnecessarily). Maybe high voltage caps, maybe rectifier tubes, or maybe the CRT tube is being driven such that the cathode current runs away, we'll find out soon enough.
At least the unobtainium parts (power trafo and CRT) appear to be ok.
Home
Help
Search
Login
Register
