|
|
|
#46
04-16-2015, 04:55 PM
|
||||
|
||||
|
Quote:
__________________
Tom C. Zenith: The quality stays in EVEN after the name falls off! What I want. --> http://www.videokarma.org/showpost.p...62&postcount=4 
|
|
#47
04-16-2015, 05:27 PM
|
||||
|
||||
|
Im getting -45.. Sounds about right.. Suppose to be -55 according to the Sams.. Realized i had to put the HV tube back in to get a correct reading.. Didn't let sit running for long seeing how I don't have pic tube connected..
__________________
Looking for an all tube or hybrid color TV set from the late 1960s, early 1970s that's in a steal cabinet.. Last edited by tvcollector; 04-16-2015 at 05:50 PM.
|
|
#48
04-16-2015, 06:04 PM
|
||||
|
||||
|
That is almost 20% high which I'd consider a bad thing. Definitely work on that H osc.
__________________
Tom C. Zenith: The quality stays in EVEN after the name falls off! What I want. --> http://www.videokarma.org/showpost.p...62&postcount=4
|
|
#49
04-17-2015, 03:17 PM
|
||||
|
||||
|
Received the fine tuning gears.. Thanks a bunch Paul.. What type of grease would you all recommend to buy?
Also received some of the tubes including the 6CG7 [6FQ7] So I'll do some voltage checks probably tonight and see if there is any difference with a good tube..
__________________
Looking for an all tube or hybrid color TV set from the late 1960s, early 1970s that's in a steal cabinet..
|
|
#50
04-17-2015, 07:32 PM
|
||||
|
||||
|
I fixed the tuner, put the gears back in, had a hell of a time getting the tension spring in place seeing how I never saw what it looked like in place, so now its in perfect to where you push in to fine tune..
Now with the Horz osc issue.. I put in the new tube, and the voltage is now +2.6 at the grid of the osc tube.. Checked voltages at the HV output tube and meter just jumps around.. Doesn't make since, notice the HV output tube was glowing bright.. unplugged the unit, luckily I didn't kill the tube... Third time powering up the damper tube next to the HV tube started the glow bright...
__________________
Looking for an all tube or hybrid color TV set from the late 1960s, early 1970s that's in a steal cabinet.. Last edited by tvcollector; 04-17-2015 at 07:42 PM.
|
| Audiokarma |
|
#52
04-17-2015, 08:27 PM
|
||||
|
||||
|
194K cold.. After power up it starts falling from being open and takes about 10min until it falls to 194k..
__________________
Looking for an all tube or hybrid color TV set from the late 1960s, early 1970s that's in a steal cabinet..
|
|
#53
04-17-2015, 08:49 PM
|
|||
|
|||
|
Quote:
is it 194k to ground with the set turned off? what is the resistance from pin 6 of the horz osc to the output from the doubler diode (the one that supply the B+).
|
|
#54
04-17-2015, 09:01 PM
|
||||
|
||||
|
meaning I hooked up my ohm meter after power off, and the meter drops as for resistance for a while until it stay steady at around 194k, and it's to ground from pin 7 on the horz osc tube..
Not sure where the doubler diode is..
__________________
Looking for an all tube or hybrid color TV set from the late 1960s, early 1970s that's in a steal cabinet..
|
|
#55
04-17-2015, 09:05 PM
|
|||
|
|||
|
ok well that does not mean anything other than caps discharging. You always measure resistance on a chassis after B+ has been off long enough to discharge, same as you always read resistance after having hooked up to let is stablize just in case there is a cap in there. you should also reverse polarity when reading resistance if it reads an odd amount when comparing to the resistance chart.
what was the pin 6 to B+ double reading?
|
| Audiokarma |
|
#56
04-17-2015, 09:11 PM
|
||||
|
||||
|
Ok, well I get 194k between pin 7 of horz osc tube to ground..
I'm not sure where to hook to B+ to measure..
__________________
Looking for an all tube or hybrid color TV set from the late 1960s, early 1970s that's in a steal cabinet..
|
|
#57
04-17-2015, 09:16 PM
|
|||
|
|||
|
there are two diodes in the power supply one has a connection to the ground, that is X1, it connect to X2, find the other side of X2 that is where you read to instead of the ground, see the Sams resistance pin reading charge, see the table explaining the symbols. some readings will be noted with symbols that tell you to read not to ground but some other place like the output of X2.
pin 6 of V11 read to the output of X2, should be 60k sometime polarity or adj pots will effect these, sometimes sams is just wrong, sometime there are big variance and it does not matter, but its a starting point, after you narrow down the offending stage. A scope is a better tool for diagnosis, but you can do a lot just checking parts if you know where to look. most of the time its going to be an open plate load resistor, a bad solder joint, a broken wire, this is why I discourage excessive cleaning and handling (wire and solder joint issues). the number one thing to do is to wiggle the tubes in the circuit. poor contacts due to heat cycling is a big problem. cleaning the pins is a solution but I prefer to not mess with it until I have a base line run. Last edited by DaveWM; 04-17-2015 at 09:23 PM.
|
|
#58
04-17-2015, 09:19 PM
|
||||
|
||||
|
Ok I think I see what you are talking about on the sams.. Give me a few to figure out to list reading..
__________________
Looking for an all tube or hybrid color TV set from the late 1960s, early 1970s that's in a steal cabinet..
|
|
#59
04-17-2015, 09:25 PM
|
||||
|
||||
|
62.5k on the side of diode X2 assuming im measuring on the right side of that diode which is coming off one of the filter caps, to pin 6 on horz osc tube..
__________________
Looking for an all tube or hybrid color TV set from the late 1960s, early 1970s that's in a steal cabinet..
|
|
#60
04-17-2015, 09:29 PM
|
|||
|
|||
|
that sounds good, try wiggling the tube, try another tube, grid emissions can be an issue, best practice is to use a known good tube.
you can often just look closely and see the problem.
|
| Audiokarma |
 |
|
|
Linear Mode
