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-   -   Crosley 9-413B Horizontal Issue (http://www.videokarma.org/showthread.php?t=276259)

Chris K 11-08-2023 09:04 PM

Quote:

Originally Posted by bandersen (Post 3254260)
15,750 Hz. Couldn't say how much range with your design.The trimmer is likely in parallel with a fixed cap. That cap might be too far off for the trimmer to compensate.

Does the trace look OK (like I know what I'm doing!:scratch2::scratch2:)

https://imagizer.imageshack.com/img924/7404/BlRxqM.jpg

https://imagizer.imageshack.com/img924/1413/MqqlpA.jpg

It looks like the picture is getting somewhat better

bandersen 11-08-2023 09:56 PM

Looking better. Where do you have your scope connected? Service info doesn't show waveforms so I couldn't say if it is correct.

Sams here for free: https://www.earlytelevision.org/pdf/..._sams_79-4.pdf

and Riders: https://www.earlytelevision.org/pdf/...03_rider_3.pdf

B2 sets the frequency and is not in parallel with a fixed cap. I'd definitely check all the associated resistors and caps in that circuit if you're still not able to get a lock. Don't trust those 220pF mica caps.

Chris K 11-08-2023 10:08 PM

They’ve been replaced with new 1% mica caps of the same value.

Chris K 11-08-2023 10:13 PM

Quote:

Originally Posted by bandersen (Post 3254278)
Looking better. Where do you have your scope connected? Service info doesn't show waveforms so I couldn't say if it is correct.

Sams here for free: https://www.earlytelevision.org/pdf/..._sams_79-4.pdf

and Riders: https://www.earlytelevision.org/pdf/...03_rider_3.pdf

B2 sets the frequency and is not in parallel with a fixed cap. I'd definitely check all the associated resistors and caps in that circuit if you're still not able to get a lock. Don't trust those 220pF mica caps.

Thanks so much for the links. I’ll go through the resistors comprehensively with the schematic from beginning to end but I have checked most of them and replaced anything that was out of spec. Every cap in the tv has been replaced and all of the micas in the deflection circuits with exact value replacements.

Chris K 11-09-2023 07:31 AM

The Riders has some great information on the specifics of the horizontal and vertical circuits including the components responsible for the sequential processing of the oscillator voltage in both. I just wish I could read the schematic! It's very blurry and the part designations are different from the readable Sams. It is, however, a great description of what happens in these circuits for a newbie like me.

timmy 11-09-2023 09:31 AM

I would double check solder connections in and around anything horizontal if there is a joint that didn’t take it could be very annoying to back track to find but worth it if you find one.

Chris K 11-09-2023 10:31 AM

Quote:

Originally Posted by timmy (Post 3254287)
I would double check solder connections in and around anything horizontal if there is a joint that didn’t take it could be very annoying to back track to find but worth it if you find one.

Ahhhh...you know the quality of my soldering well!!!:yes::yes::yes::yes::yes:

timmy 11-09-2023 10:43 AM

Quote:

Originally Posted by Chris K (Post 3254288)
Ahhhh...you know the quality of my soldering well!!!:yes::yes::yes::yes::yes:

No it’s not that I have made many mistakes and then having to go back and look over what I did and yes found many dumb mistakes I have made.

Yamamaya42 11-09-2023 10:53 AM

Quote:

Originally Posted by timmy (Post 3254289)
No it’s not that I have made many mistakes and then having to go back and look over what I did and yes found many dumb mistakes I have made.

can't be THAT bad, I mean, you are not like this person, are you?:D
https://i0.wp.com/makezine.com/wp-co...ng?w=848&ssl=1

timmy 11-09-2023 10:59 AM

Quote:

Originally Posted by Yamamaya42 (Post 3254290)
can't be THAT bad, I mean, you are not like this person, are you?:D
https://i0.wp.com/makezine.com/wp-co...ng?w=848&ssl=1

Lol well he is probing for a problem

kvflyer 11-09-2023 11:38 AM

Quote:

Originally Posted by Chris K (Post 3254280)
Thanks so much for the links. I’ll go through the resistors comprehensively with the schematic from beginning to end but I have checked most of them and replaced anything that was out of spec. Every cap in the tv has been replaced and all of the micas in the deflection circuits with exact value replacements.

When you replaced every resistor and capacitor with the exact value, maybe the set was adjusted in the past for a failing component and is therefore way out of adjustment.

I hate to beat a dead horse but I was lucky to find a simple problem in my RCA 630TS where the horizontal was way off frequency. I found the Horiz Freq transformer cranked all the way to one end, probably to compensate for failing components. When I put new, on value parts in, the adjustments were rock solid and in the middle of the range.

Just a thought.

bandersen 11-09-2023 01:47 PM

Absolutely! It's unusual to NOT need to make adjustments after recapping.

bandersen 11-09-2023 01:49 PM

The original Riders hardcopy is hard to read as well. Best we have unless someone has an original Crosley service manual.

Chris K 11-11-2023 10:24 AM

I had my scope connected right after the horizontal frequency trimmer. Probably the wrong spot but I do have a sawtooth at 15.75 kHz

Penthode 11-22-2023 01:29 PM

Quote:

Originally Posted by Chris K (Post 3254320)
I had my scope connected right after the horizontal frequency trimmer. Probably the wrong spot but I do have a sawtooth at 15.75 kHz

The horizontal frequency is actually 15,734.26573426573 Hz. Or rounded off 15.73 kHz


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