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  #16  
Old 05-05-2018, 01:27 AM
Electronic M's Avatar
Electronic M Electronic M is offline
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The vert tube is usually not able to take out the HV... granted some sets take boost voltage from the flyback to feed the vert and if the vert stage has an issue causing it to overload the boost that can also load down the HV indirectly.

The fly sounding strained sounds like a more telling lead... if the h osc is too far off the correct frequency then the HV output and sweep will collapse. The entire h output/fly/yoke is a big tuned circuit and needs the right frequency to work. Also the waveform and amplitude need to be at least close to the right for the system to work... when it it right it should be a high pitched whistle tone no screeching or crackling.

Make sure to get a schematic...TVs are complex and diverse so flying blind without a schematic is going to waste more money in burning through your valuable time than buying 10 schematics will cost.
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  #17  
Old 05-05-2018, 01:38 AM
Sealtest Sealtest is offline
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Quote:
Originally Posted by Electronic M View Post
The vert tube is usually not able to take out the HV... granted some sets take boost voltage from the flyback to feed the vert and if the vert stage has an issue causing it to overload the boost that can also load down the HV indirectly.

The fly sounding strained sounds like a more telling lead... if the h osc is too far off the correct frequency then the HV output and sweep will collapse. The entire h output/fly/yoke is a big tuned circuit and needs the right frequency to work. Also the waveform and amplitude need to be at least close to the right for the system to work... when it it right it should be a high pitched whistle tone no screeching or crackling.

Make sure to get a schematic...TVs are complex and diverse so flying blind without a schematic is going to waste more money in burning through your valuable time than buying 10 schematics will cost.

I will certainly try adjusting to see if I can get the flyback to sound somewhat correct. Would the adjustment being off cause no voltage to go through the plunger though? Like I've mentioned before I'm really new to TV's so there's quite a bit of confusion on my end. Dang audio repair is so much easier.

Just ordered the schematic, so that'll help hopefully.
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  #18  
Old 05-05-2018, 05:45 AM
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Electronic M Electronic M is offline
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The "plunger" (I presume you mean the suction cup at the end of the HV lead) that connects between the side of the CRT and HV cage is the HV lead so yes off freq can kill the HV. Hard to tune it without an oscilloscope, Best to get a scope, measure dist between h sync pulses on video sign then hook the scope to h osc and tune it to match.
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Last edited by Electronic M; 05-08-2018 at 10:46 AM.
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  #19  
Old 05-07-2018, 01:55 PM
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Notimetolooz Notimetolooz is offline
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Here is one of my favorite diagonstic tricks that newbys can try. I doesn't take any special exotic equipment. The fluorescent bulb doesn't have to be good, the glass tube has to be still sealed though.
If the bulb lights when held near the horizontal output, flyback or yoke leads then the horizontal output circuit is working. Before compact fluorescent bulbs were available neon bulbs were used. I guess now the compact fluorescent bulbs are being phased out.
The horizontal circuit has to be working before the CRT High Voltage (HV) will be produced.
The filament voltage for the HV rectifier tube comes from the flyback transformer. The filament usually can't be seen anyway on that tube.
Do get a schematic and learn how to read it.
Do be very careful around the B+ and Boost voltage. Stay at least a couple of inches away from the tube caps, the voltages there can jump when the set is working.
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  #20  
Old 05-08-2018, 10:40 AM
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Notimetolooz Notimetolooz is offline
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There are generally three sources of schematics for products of this vintage.
Sams, Riders and Beitman published schematics. Sams usually has the most info like parts lists and photos. Many times you can download Riders and Beitman for free.
Go to the link below. Click on the top check under 1955 of the TV Diagrams section. That will download that pdf file. Look on page 149 of the manual (page 145 of the pdf file). What is the model number by the way?
http://www.americanradiohistory.com/Beitman-Manual.htm
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