Ok Guys I got One for You Here lets see if you can help me out

[Rainner]

I have a 1951 porthole tv everthing was working fine until tried to clean it and broke the wire that jumpers two tubes together (6bq6gt tubes for the hor. output output I think LOl).V24 and V18 On my Sceamtic, I replaced the wire that was going to them and the wire that was jumpering over top and now I have no pic and no sound Anyone know why this could be or what i might do about it.


Thanks for any help
DON

[Electronic M]

Have the paper and electrolytic capacitors been replaced? If not operating it in that state is sort of like 'Russian roulette'....It could fail at any time.

In regards to picture:
If the capacitors have been replaced: Did you run the set with the jumper disconnected(not a recommended practice)? If you replaced the lead connecting the HO tubes top caps to the flyback; are you sure you connected the new lead to the same terminal as the old lead?...If not that is likely your problem with picture barring the possibility that you disturbed something else.

Regarding sound:
I don't think there is anything common to the horizontal and sound sections other than the main power supply. Meaning you either also harmfully disturbed something in the audio section or the main B+ power supply has failed.

Things to check: Do the tubes light? If not check for a blown line fuse and or filament fuse.
Is there B+ voltage within + or -20% of that listed on the schematic? If previous is yes and you have NO B+ then check for blown B+ fuse and B+ rectifier tube. If the voltage is way off start checking components in the power supply circuit.
Do you have HV at the CRT? To check this either use a 20KV rated HV probe, or holding a plastic handle insulated screwdriver by the handle, connect the blade to the chassis ground with a clip lead, and then bring the blade near the HV connection to the tube with the set running....You should draw an arc within 1/2"-2" of an exposed metal HV contact.
Do you hear any hum from the speaker?
Do you hear any noise from the speaker when turning the volume control of changing channels on the sets tuner?

[Rainner]

I will Look in to those things and let you know. The caps have been replace and there is no hum. The crt lights up there just is no picture form my dvd player to the tv and there was before I broke the lead.

[Rainner]

not sure if I conected the lead to the right terminal on the fly back how do i know for sure im new to all this lol

[Electronic M]

Originally Posted by Rainner

not sure if I conected the lead to the right terminal on the fly back how do i know for sure im new to all this lol

If you have the schematic you can use it to trace the connections on the flyback, and if it is a Sam's schematic then you can use the listed resistance measurements on the flyback to aid in doing so.

If the screen lights then the fly is working fine, and you have a signal problem.

[Sandy G]

In any case, you have a VERY pretty blonde Porthole.. Not many of them around, I would think..

[Rainner]

ok guys I got everything going on this tv now but what causes sound to bleed into the picture.

[Electronic M]

Miss adjusted fine tuning, missing shields, bad filter/paper type caps in the sound section(replacements can fail too), filament-cathode shorts within a tube, wiring shorts, and video alignment can all be causes. My advice get a scope preferably dual channel (so the sound can be monitored and compared to the video) and follow the video signal from the CRT back to the video detector to see if it is associated with any particular video stage.

[zenith2134]

The advice to monitor sound and video simultaneously with a dual-trace scope is certainly a step in the right direction re:fixing your Porthole.

A quick 'n dry test for if your I.F. stages are lined up is to inject video of a Center Cross pattern right after the detector and note the response while fine tuning the station.

Once I had a b/w set with broken fine tuner mechanism and it made things seem like a full alignment would be required .