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#31
02-22-2023, 01:29 PM
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I'm sure that if you follow his examples in the video, it should be OK, he may even see this thread sooner or later and offer some sagely advice, having done this so many times before.
__________________
=^-^= Yasashii yoru ni hitori utau uta. Asu wa kimi to utaou. Yume no tsubasa ni notte. いとおしい人のために 
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#33
02-22-2023, 01:51 PM
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BTW, I didn't check video signal with the scope but I had continuity between the 6AU6 plate and the CRT so there's no mechanical issue. The coils are good and I changed the capacitor just for good measure. Still no image getting through...just sound and the bright and full screen raster.
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#34
02-22-2023, 02:10 PM
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What checking with the scope would tell is if the video is getting to the cathode of the CRT at the needed amplitude for a picture, w/o any distortion, if it is, the sync may be SO FAR out of wack that it MIGHT obscure video display ( unlikely, but who knows.) , or the voltages at the CRT are so far off, it just can't let it show video, assuming that it's good enough to in the first place.
__________________
=^-^= Yasashii yoru ni hitori utau uta. Asu wa kimi to utaou. Yume no tsubasa ni notte. いとおしい人のために
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#35
02-22-2023, 02:18 PM
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#36
02-22-2023, 02:20 PM
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Last edited by timmy; 02-22-2023 at 02:40 PM.
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#37
02-22-2023, 02:50 PM
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A few things. You had a very rare after market glass Amperite ballast
 That's only the second 303 glass ballast I've seen in many years of looking.They do not have a shield around them. They are prized because they actually regulate the current to the tubes. They're filled with hydrogen gas and have finely twisted iron wires. The hydrogen seeps into the iron and affects it's resistance. When the wire get's hot, some of the hydrogen is forced out and the resistance drops. That causes the wire to cool and it absorbs more gas. That perforated metal tube is the stock ballast. It's just some resistance wire on a mica wafer like a toaster. That metal shield is to keep fingers away. Here are four types. Left to right. Clarostat aftermarket replacement. Stock Motorola ballast. Amperite glass ballast (this is a more common '459 type) Homebrew using Capacitors, resistors and thermistor. 
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#38
02-22-2023, 02:52 PM
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This is my current design using diodes. Compact enough to fit in the original metal tube.
 Andersen[/url], on Flickr
Last edited by bandersen; 02-22-2023 at 03:55 PM. Reason: OOps! Wrong image
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#39
02-22-2023, 02:56 PM
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Note this is for the 17A435459 ballast. The '303 is very similar but you will need to move one wire. I believe it's moving the connection from pin 6 to pin 5.
Last edited by bandersen; 02-22-2023 at 02:59 PM.
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#40
02-22-2023, 05:01 PM
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http://suzaku.live-evil.org/0222231655.jpg
I knew i had one! SYLVANIA 40a1 ballast tube. Not sure what it can be used in. :O
__________________
=^-^= Yasashii yoru ni hitori utau uta. Asu wa kimi to utaou. Yume no tsubasa ni notte. いとおしい人のために
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#41
02-22-2023, 05:32 PM
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#42
02-23-2023, 09:50 AM
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OK, so THIS is what it's used for,  no idea where I found it!
__________________
=^-^= Yasashii yoru ni hitori utau uta. Asu wa kimi to utaou. Yume no tsubasa ni notte. いとおしい人のために
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#43
02-23-2023, 10:30 AM
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__________________
Goodness comes from getting the basics right, glory is to be found in tending to the details.
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#44
02-23-2023, 04:37 PM
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Thanks everyone for their input and especially to Bob and others who took the time to post design drawings and their advice. I think I will give Bob's diode and thermistor design a try first as I have several of the CL-90s and a pack of 1N5408 diodes. I actually lost sleep last night over my clumsiness in losing the very rare 303 glass ballast in my mini-Hindenburg event. Oh the Humanity! Klutz!
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