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B&K 1077B no video - problem solved
#6

I found a schematic and think I have the problem traced down to the minus power supply. I have very low voltages that go to zero when powered up, and the higher voltages are cut in half. I opened the resistors coming from each source and noted any voltage changes in checking for something loading down the circuit. I ended up disconnecting everything - no load and have only around -100v. Should be -220 or around. Checked the power trans and it is putting out the correct voltages. So ... getting interesting. The B+ is fine, its the B-. And, yeah, it powers the ICs, vert transistors, and a bunch of other stuff. Interestingly, the B- supply stays powered up even when the switch is in 'standby'. It just cuts the B+.

Rich,
That 1077b is hard to beat! I have a couple more modern ones, but for simplicity and brute force, that 1077 rules! It is my 'go to' tester for TVs, kinda like my Precise 111 is my go to tube tester. I DO really like the Sencore stuff. They seem to be really well built and straightforward and accurate.

If I could find the place called "Somewhere", I could find "Anything" Icon_confused

Tim

Jesus cried out and said, "Whoever believes in me , believes not in me but in him who sent me" John 12:44


Messages In This Thread
B&K 1077B no video - problem solved - by TV MAN - 02-11-2025, 01:26 PM
RE: B&K 1077B no video - by TV MAN - 02-11-2025, 02:03 PM
RE: B&K 1077B no video - by radiorich - 02-11-2025, 09:01 PM
RE: B&K 1077B no video - by TV MAN - 02-11-2025, 09:11 PM
RE: B&K 1077B no video - by radiorich - 02-11-2025, 11:07 PM
RE: B&K 1077B no video - by TV MAN - 02-12-2025, 12:41 AM
RE: B&K 1077B no video - by radiorich - 02-12-2025, 01:55 AM
RE: B&K 1077B no video - by TV MAN - 02-13-2025, 04:04 PM
RE: B&K 1077B no video - by radiorich - 02-13-2025, 10:59 PM
RE: B&K 1077B no video - by TV MAN - 02-15-2025, 12:40 AM



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