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Old 03-24-2020, 01:53 PM
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Yamamaya42 Yamamaya42 is offline
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Join Date: Nov 2018
Location: Round Rock TX
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Quote:
Originally Posted by Electronic M View Post
I'm not surprised it passes color video passband of monochrome sets was originally 4.5MHz in late 53 they mixed color into monochrome video 3.58MHz and up. And 55 and later models started being designed to limit response over 3.5MHz. Some pre-54 sets actually had color wheel NTSC adapters connected to them with no RF/IF alignment change.

The soild state 5V4 damper may fail in your application... that part was designed for 60Hz guitar amp power supplies its diodes may not switch fast enough for horizontal rate and damper service is at the edge of voltage ratings of the tube...the solid state part may or may not be rated to handle a voltage spike that would harmlessly arc the tube.... I'd stick with a tube unless you are fine blowing the SS part to learn if it works.... Alternatively you could take the base off a dud octal tube, and spec out a diode that will handle what the circuit can supply and make your own.
The current tube in it is likely just fine. Blue glow is usually fine (stray electron bombardment of the glass), but purple/Violet is usually indicative of gas leakage.
Well something is not right, cause as of now, I have very low HV, with the new rect tube, I can hardly get 4-5 kv, where it should be 9-10kv.
Be it caused by weak tubes, or really out of tol resistors , not sure, still looking through it for crappy resistors, and IMOH, I can't really see how it can work correctly with ones as bad as I mentioned off the video output plate that's 28.18% off 3.3k :O (not replaced yet, don't have bulk 1w ), but I'm sure I will find others like it
But I can tell that both the HOT & damper have been replaced before, as they are not RCA tubes, where as most every other one in there is, this tends to tell me that of all the tubes that were going to fail in this, they were most likely the first to go, so I tend to suspect them being a problem, but I have no way to try a substitute. So I will try to find new (well, new as I can find,) and see what happens.
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