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Old 03-15-2018, 07:40 PM
dieseljeep dieseljeep is offline
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Join Date: Jul 2010
Posts: 7,562
Quote:
Originally Posted by Electronic M View Post
It does make one worry about VK when a resto topic for an early color set that only 9 examples of are known to remain goes straight into a discussion of stupor glue... I've never had good luck gluing my wounds, so I save the stuff for certain resto tasks such as fixing the occasional terminal strip wafer snapping in two.

I was able to make all the vertical stage resistors match the schematic from the ETF. http://www.earlytelevision.org/pdf/m...905_manual.pdf
Several were marked different values from the schematic, and some of the different ones were clearly replacements that were tacked in ages ago. Changing the resistors did not solve or change the problem...Scoping revealed it is closer to running at 3X correct frequency than the 2X I assumed earlier.
I could not find my RC decade box, but jumping capacitors and resistors in did not help/change much.
Voltage checks indicate there are major issues in the output...The grid of V15 should be -14V to -2.8 it seems to only be adjustable from -3V to 0V...The plate voltage is low and the cathode is high indicating excessive current flow in the output tube (big shocker given the grid voltage lol). The linearity control seems to be ineffective.
I really wish I had sam's 371 right now...I've got every sam's folder from 101-580 EXCEPT for 371 (which contains the folder for this set)...Just my luck. I'd really like to cross reference the sam's lit.

Presently I'm stalled on this project...Not by the set but by the flu. I've been running 102 fevers on and off all week and have been feeling generally miserable. No basement bench time for me for now.
That was the wrong poster to pay attention to.
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