Had a beautiful bright picture after replacing all the electrolytics. I moved the set 10 feet and lost brightness, The brightness control was working fine but now has no effect. Does anyone have a sams 909-2 they could email or scan? I went to my local Library for the folder but folder 2 is missing, of course. This is chassis CTC-19U
Thanks for any help or thoughts.
Jim

Check the easy, obvious stuff first. If it worked find and then you moved it, chances are a connection came off or a tube worked loose. Check the connection to the brightness knob, the wires like to break off or get weak when you take the chassis out, and that one last bump might have knocked if off totally. Wiggle all the tubes, and make sure that nothing got bumped crooked. Check that any repairs you made are good connections, and make sure that any wires that might have been stressed or flexed in the process of repairing things are connected well.

-Ian

Thanks for the tips Ian,
But I already tried all the things you mentioned. I pulled the chassis last night and spent a few hours checking for loose connections, tubes etc.. No luck at all. Can't see where anything is touching or grounding to cause a problem either. The CRT tests strong and I can get an arch at the cap of the horizontal output tube. I hope it's a simple fix, If I can get the schematic I'll trace the leads from the 3 taps on the brightness control and try to solve the problem. I've tested all the resistors in the high voltage section and didn't find any problems. All bad tubes have been replaced also.
It's a mystery but aren't these vintage electronics always a work in progress?
Jim

I would actually ohm out the brightness control, and ohm out the wires leading to the control, if you haven't already. I have seen wires break inside the insulation. If this were a modern set I'd say to check the screen voltage control on the flyback, but I know this doesn't have one. It _sounds_ like a loose something, since it appeared when you moved it, but typically with intermittant stuff if you bang on it enough you'll see it flicker in and out. Without a schematic you won't be able to see stuff as easily, but you should be able to follow the wires back from the brightness control and start checking the caps and resistors in that circuit. Maybe a resistor opened or drifted. Hard to say, but I know how frustrating it can be to have something working and then >fzt!< it has something else wrong with it.

Have you recapped the whole set or just replaced the electrolytics?

-Ian

Jim,

I don't have the Sams, but I do have the RCA factory manual on it. I put in on the Web here, see the two halves at these links:

http://home.mindspring.com/[email protected]/CTC19p1.jpg

http://home.mindspring.com/[email protected]/CTC19p2.jpg

Note that there are several notes in the schematic about low brightness problems. Here are the parts that were found to be causes, according to whatever technician owned this manual:

R233 (180k) & R234 (6.8M) on PW200 board. Note says brightness fluctuating up & down.

R750 (2.2M) on PW700 board; note says low brighness cold, then brightens up after time.

Have you resoldered all the tube socket pins, and all the PC-board-to-chassis ground connections?

Let me know if these links work, or I can send you the files by eMail if you can get 1Mb files. Please note that I will have to erase those in the next few days due to webspace limits, so I am hoping that you can download and print, if they look like they will be readable. Please eMail direct if you want me to eMail full size.... [email protected]

I'll be gone until along in the evening, but I should be able to send it later tonight.

Charles

Got the schematics Charles, Thanks!
I printed the pages and can read them well enough to start troubleshooting.
I'll check those resistors and the tube socket pins,ground connections as you suggested. I Just pulled the chassis again and will work on it some more tonight, I'll post my progress later.
Thanks again.
Jim

That's a cutie!
It always seemed funny to me to put a small TV in a console cabinet.

The problem was either an out of spec resistor (R234 6.8Meg) or one replacement electrolytic may have made contact under the chassis, I replaced both the resistor and lytic..problem solved. The brightness control works great. Looks much better now, Thanks to all for the help. I really want to have this one working when the "Color" Honeymooners DVD's are released the end of June.
Does anyone know the model number of this set or the year 1966,1967? and was this a remote set? or any info on this mini console.
Jim

That's a cutie!
It always seemed funny to me to put a small TV in a console cabinet.


Yes, I find those small-screen consoles cute too... Anyone seen one of those 13" Toshiba wood color consoles on long legs; the one with the same CRT socket as 21" roundie? Sears sold a bunch of them, and I had one that was a non-UHF model that is now with Tom Ryan. I was told it was a '59-'63 model.

Charles

The problem was either an out of spec resistor (R234 6.8Meg) or one replacement electrolytic may have made contact under the chassis, I replaced both the resistor and lytic..problem solved. The brightness control works great. Looks much better now, Thanks to all for the help. I really want to have this one working when the "Color" Honeymooners DVD's are released the end of June.
Does anyone know the model number of this set or the year 1966,1967? and was this a remote set? or any info on this mini console.
Jim

Glad to help, and happy to hear it's fixed! The AK community has helped me plenty too, so I am pleased I was able to do a little something.

Charles