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Restoring a Predicta Tandem
#5

First I want to say that I am new to fixing an old tv, for the most part I can read a schematic, I know hot to solder, and Im generally good at trouble shooting. I'm an electrician by trade so I have a general knowledge of electricity and what caps and resistors do and are used for. But by no means am I a tv repair man. So please be patient with me.

Last night when I tried the set all the tubes and the dial light lit right up. Tonight I went to try and test for power by the tuner, and when I plugged it in nothing lit. Not the tuner dial or the filaments. I grabbed my meter and saw I have power going though the switch. Then I metered from one leg of the 120v feed to the fusistor R78 and got 80v on one side and 118 on the other. Then I tested the resistor R80 and with one lead of the tester on the power feed and the other on each of the terminals I got 118v so it doesn't seem to be creating resistance. Then I unplugged the set from the wall and hooked up one lead of my meter to where the hot wire attaches to r80 then metered each terminal and still got no reading on the second one, which looks like the 8 ohm terminal. I also did the same test with what I think is R79 and it read 118v on both sides also. Its hard to tell from the picture because its kind of light, but the part I tested is a thick round disc it almost looks like a black mentos with a lead coming out of each side.

The other thing is what is the best way to clean the main board. I tried to follow the diagram and just check each resistor on the main board one at a time, and a few of them were open. Im wondering if its just crud on the board. The whole thing is dusty and sticky so Im wondering if its keeping me from making a good connection?

Also does your average DVOM have enough power to get a cap to charge? I set the meter to Diode test and I tried to see if C1 would charge and it read open.

I don't want to just go nuts and replace every single part of this set to make it work, Im trying to see what is actually going on. Or am I looking at this the wrong way and I should just replace everything? When you read about these Tv's on the internet it makes them sound like theyre very unreliable. But things usually get blown out of proportion on the internet, if they were all lemons I think theyd all be in a landfill by now and we would have nothing to restore....

Also is it worth leaving the wire wrapped connections intact, but cutting the wires in the middle and putting a male and female spade connector on them so you can service the board easier down the road? Or will they pick up interference and just cause trouble?


Messages In This Thread
Restoring a Predicta Tandem - by apERNA1985 - 02-27-2018, 02:39 PM
RE: Restoring a Predicta Tandem - by Radioroslyn - 02-27-2018, 05:01 PM
RE: Restoring a Predicta Tandem - by Radioroslyn - 02-27-2018, 06:40 PM
RE: Restoring a Predicta Tandem - by apERNA1985 - 02-27-2018, 11:08 PM
RE: Restoring a Predicta Tandem - by Radioroslyn - 02-28-2018, 03:46 PM
RE: Restoring a Predicta Tandem - by Bob Andersen - 03-01-2018, 12:27 PM
RE: Restoring a Predicta Tandem - by Bob Andersen - 03-01-2018, 01:03 PM
RE: Restoring a Predicta Tandem - by apERNA1985 - 03-01-2018, 01:13 PM
RE: Restoring a Predicta Tandem - by apERNA1985 - 03-01-2018, 01:18 PM
RE: Restoring a Predicta Tandem - by Bob Andersen - 03-01-2018, 02:55 PM
RE: Restoring a Predicta Tandem - by apERNA1985 - 03-06-2018, 11:56 AM
RE: Restoring a Predicta Tandem - by Radioroslyn - 03-06-2018, 06:07 PM
RE: Restoring a Predicta Tandem - by apERNA1985 - 03-06-2018, 08:01 PM
RE: Restoring a Predicta Tandem - by apERNA1985 - 03-07-2018, 08:54 AM
RE: Restoring a Predicta Tandem - by gregb - 03-07-2018, 10:06 AM
RE: Restoring a Predicta Tandem - by apERNA1985 - 03-07-2018, 11:39 AM
RE: Restoring a Predicta Tandem - by Bob Andersen - 03-07-2018, 12:24 PM
RE: Restoring a Predicta Tandem - by Radioroslyn - 03-07-2018, 01:06 PM
RE: Restoring a Predicta Tandem - by Bob Andersen - 03-07-2018, 01:29 PM
RE: Restoring a Predicta Tandem - by TV MAN - 03-11-2018, 06:39 PM
RE: Restoring a Predicta Tandem - by Arran - 03-13-2018, 04:00 AM
RE: Restoring a Predicta Tandem - by TV MAN - 03-13-2018, 09:03 AM
RE: Restoring a Predicta Tandem - by apERNA1985 - 03-17-2018, 09:19 AM
RE: Restoring a Predicta Tandem - by Bob Andersen - 03-19-2018, 11:47 AM
RE: Restoring a Predicta Tandem - by apERNA1985 - 03-19-2018, 12:03 PM
RE: Restoring a Predicta Tandem - by Radioroslyn - 03-19-2018, 12:57 PM
RE: Restoring a Predicta Tandem - by Bob Andersen - 03-19-2018, 03:25 PM
RE: Restoring a Predicta Tandem - by Arran - 03-22-2018, 04:55 AM
RE: Restoring a Predicta Tandem - by Bob Andersen - 03-22-2018, 08:31 PM
RE: Restoring a Predicta Tandem - by apERNA1985 - 03-23-2018, 08:17 AM
RE: Restoring a Predicta Tandem - by Arran - 03-24-2018, 01:27 AM
RE: Restoring a Predicta Tandem - by TV MAN - 03-29-2018, 11:12 AM
RE: Restoring a Predicta Tandem - by apERNA1985 - 03-29-2018, 12:19 PM
RE: Restoring a Predicta Tandem - by apERNA1985 - 04-06-2018, 10:57 AM
RE: Restoring a Predicta Tandem - by gregb - 04-06-2018, 12:13 PM
RE: Restoring a Predicta Tandem - by apERNA1985 - 04-06-2018, 03:52 PM
RE: Restoring a Predicta Tandem - by gregb - 04-06-2018, 04:06 PM
RE: Restoring a Predicta Tandem - by gregb - 04-06-2018, 06:36 PM
RE: Restoring a Predicta Tandem - by Arran - 04-07-2018, 04:26 AM
RE: Restoring a Predicta Tandem - by apERNA1985 - 04-26-2018, 05:40 AM
RE: Restoring a Predicta Tandem - by gregb - 04-26-2018, 09:01 AM



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