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  #1  
Old 11-11-2019, 09:58 PM
vortalexfan vortalexfan is offline
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Quote:
Originally Posted by Kevin Kuehn View Post
I meant they show a 6AK5. For starters just measure the plate pins, that's where we're looking for B+.
I just checked through my tube stash and I did end up finding a 6AG5 tube that tested good yet on my tube tester.

Also checked the voltages from the top without the tubes in and they were spot on to where they should be, on pins 1 and 2 of the 6J6 socket I was getting around 193 volts DC, and pins 5 and 6 of the 6AG5 socket I was getting around 193 Volts DC as well, which I think will drop down to the readings on the voltage chart when the tube is in the socket.

Also I think I might of figured out what's going on, a couple of the center pins on a couple of the 6AU6 sockets broke off on the bottom of the Chassis, one of them is in Video the IF Circuit the other one is the Sound IF 6AU6 socket.
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Old 11-11-2019, 10:44 PM
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Kevin Kuehn Kevin Kuehn is offline
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Quote:
Originally Posted by vortalexfan View Post
Also checked the voltages from the top without the tubes in and they were spot on to where they should be, on pins 1 and 2 of the 6J6 socket I was getting around 193 volts DC, and pins 5 and 6 of the 6AG5 socket I was getting around 193 Volts DC as well, which I think will drop down to the readings on the voltage chart when the tube is in the socket.
I have no idea how you're measuring 193 volts dc now if the those tubes are being fed b+ though R13, which a while ago you said you measured 158.4vdc on the input side and 154.4 on the output.
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Old 11-11-2019, 10:51 PM
vortalexfan vortalexfan is offline
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Originally Posted by Kevin Kuehn View Post
I have no idea how you're measuring 193 volts dc now if the those tubes are being fed b+ though R13, which a while ago you said you measured 158.4vdc on the input side and 154.4 on the output.
Why, am I not supposed to be getting 193 Volts there?

Also I'm finally getting some response out of the tuner, it seems that two of my 6AU6 sockets will need replacing unfortunately, but the good news is that the voltages on the 6AU6 Video IF tubes are spot on to what they are supposed to be, I'm just not getting a good connection between the tube and the socket because of the sockets being faulty, (the center grounding lug is busted off on both of them and the sound IF socket some how popped one of its retaining rivets loose) and so there's no reference to ground with them anymore.

So anyways I'm going to have to see if I can find a couple of phenolic wafer style 7 pin tube sockets to match up with the original sockets and install them in place of the broken/intermittent sockets.
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Old 11-11-2019, 11:06 PM
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Kevin Kuehn Kevin Kuehn is offline
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Originally Posted by vortalexfan View Post
Why, am I not supposed to be getting 193 Volts there?
The sams schematic and voltage chart don't show anywhere near that voltage on those pins. Also as I mentioned before, the schematic shows the tuner b+ being fed by R13. If you had 158v on the input side of R13, and 154 on the output. There is no way for that voltage to increase on the load side, because the more current you pull thought that resistor, the lower the voltage will go on the output side.

Last edited by Kevin Kuehn; 11-11-2019 at 11:11 PM.
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  #5  
Old 11-11-2019, 11:19 PM
vortalexfan vortalexfan is offline
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Originally Posted by Kevin Kuehn View Post
The sams schematic and voltage chart don't show anywhere near that voltage on those pins. Also as I mentioned before, the schematic shows the tuner b+ being fed by R13. If you had 158v on the input side of R13, and 154 on the output. There is no way for that voltage to increase on the load side, because the more current you pull thought that resistor, the lower the voltage will go on the output side.
Maybe I mismeasured something, all i know is that I have a picture from my converter box on the TV now, and the picture is rock solid except for the picture not being centered horizontally and vertically, and no audio still.
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Old 11-11-2019, 11:33 PM
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Yeah.
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  #7  
Old 11-12-2019, 12:24 AM
vortalexfan vortalexfan is offline
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Originally Posted by Kevin Kuehn View Post
Yeah.
Another update, I now have rock solid audio, the Audio IF was out of alignment so I fixed that, and now I have perfect audio to go with the rock solid picture.

Now I unfortunately am having issues with my high voltage again where my picture is intermittently going bright and dim, and I have a feeling it has to do with that 1 Meg 1 Watt resistor in line with the High Voltage cap for the Picture tube.
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