Repair of a vintage 60s Fisher 450t solid-state stereo receiver. Part 4/? FM tuner and mpx repairs

Addressing the FM problems. FM output goes to zero after a time. no stereo operation.
let's find out why...

[@steveoszman8746]

Great resurrection of a fine old receiver. You have aided in the salvage of many fine bits of gear here. Thanks for your patience in shooting these vid.

[@mjg263]

Very well done, that’s going to be a fine, reliable receiver for many years to come!

[@sirsuse]

Cool receiver. Great work on it. Thanks Jordan.

[@jtee9548]

Good Lord man. You've got enough hours into that thing to cover the cost of a nice 60's Buick 😁!!

[@michaelwitas9482]

The Fisher 395 and 505T receivers were similar. If you can find the service info for those models, its possible that they may show the board modifications that are present in your 450T.

[@3dsmaxrocks699]

Instant thumbs up

[@Scott.Newmaster]

Wear the ban as a badge. If more would quit with the P.C crap "things" wouldn't allowed to hide.

[@3dsmaxrocks699]

I'm troubleshooting a little radio shack am/fm SW radio that won't power on. When I test some of the zener diodes in diode mode the LCD screen comes alive. It's supposed to always be on even if unit is off since it's a alarm clock too. Right now nothing works. Any ideas why probing a zener diode would wake up the LCD screen? I'm a hobbyist not a pro BTW

[@ralphj4012]

Pure guesswork on my part (so may be wrong) but if 'probing' means using the ohms or diode range on a DVM, then a voltage (which can be anything between about 0.5V and, in some cases, 5V) is being introduced and that is enough to power up many things. Touching power rails can also be enough to 'power' LCD's.

[@3dsmaxrocks699]

@@ralphj4012 Turns out it was a cold solder joint. Would've never seen it without a digital microscope thingy. Thanks for your input!

[@v12alpine]

Very nice receiver.

[@williamsquires3070]

(@23:26) The problem is that violence begets violence; you might solve the “problem” in the short term, but there’s always someone with a bigger stick (or gun.)

[@JordanPier]

True, and often that violence triggers revengeful behaviors on the receiving parties. It can also be a learned experience so that the offending party doesn't repeat bait and switch - especially if enough participation from all parties occur on the punishment front

[@richardbrobeck2384]

jordan I read your post and I agree and those mallory capacitors are just plain junk !

[@chetpomeroy1399]

I see it's a post-CONELRAD receiver. After almost 60 years in operation, it would be reasonable to assume those white plastic electrolytic caps all needed to be replaced. Those PC board traces look really delicate. (22:00 -- I personally don't approve of that tactic, and I know it's hard, but a good dose of emotional regulation and impulse control are musts to avoid any prospective consequences. Let karma take care of that jerk.)

[@jamiyajoseph1961]

🙂 promosm

[@kennethiman2691]

Your FB story was hilarious. I am on pretty much lifetime probation on FB for telling the truth the basement dwelling fact checkers don't agree with.

[@Evokvn]

First

[@Poppinwheeeeellllllieeeeez]

First bell head

[@zx8401ztv]

it's a shame that there are so many selfish people around. The grabbing type of people. Another discription is arseholes (a technical term) :) I can't understand selfish people. A waste of d.n.a.

[@excentor]

second =)

[@Poppinwheeeeellllllieeeeez]

Second bell head