I didnt see a welcome forum so ill give you a quick intro . My name is David. I farm, am a EMT, and love music, radios, and old stuff. Ive spent the last several years convincing my dad to give me his fathers radios. I ended up quilting him into giving them up. I ask him what his father would have wanted - them to sit in a closet of get out and be used. As far as he remembers he made most of the radio and speaker stuff. Ive got most of the paper work but not enough of it to really help with any trouble shooting.

The radio is a Fisher. There are a couple pre amps and a few amps in the cabinet. The woofers are EV 30W ULF (which I dont yet have) The treble driver is a Model T250 EV, The speaker boxes also hold a EV T35 VHF driver and a EV SP12 Speaker. For some reason these speakers have a hum that my cheap 8ohm speakers do not have. The hum is there with the amps powered and the fisher turned off. I have no idea what the knobs on the speakers really do. I am fairly new to vintage radios but enjoy them thus far.

You are very blessed to have all this great stuff handed down to you from your grandfather, I wish I knew him since he must have loved music and its reproduction at home. All this old equipment needs to be serviced before you can use it. Mainly the capacitors have to be replaced, especially the power filters. Do not continue to play it like this. Maybe there is someone in your area who can help you, post what city you are from.

Hi David, welcome to the forum.

I agree with Lou completely. You have a formidable restoration project on your hands. If you're new to this sort of thing, then be advised, this is no job to tackle alone.

If this gear has been sitting idle for years as you say, each and every piece of it will need attention, beginning with power supply overhauls (especially recapping) and verifications for each piece, the preamps and your Fisher tuner included. This is critical, and for the sake of safety (especially your own), and as Lou says, the gear should not be operated until this is done. And that is only the beginning.

I most sincerely advise you to get hold of a qualified service tech who knows tube gear thoroughly, and get his direct, hands-on help. Your local ham radio club might be the best place to go searching for help.

Best of luck with your project.

Larry

Agree with all. You probably have introduced a ground loop which can be worked out. Of course the capacitors already mentioned need to be replaced for sure.

I dont use it for say Ive turned it on here and there for a few minutes but not for long periods of time. Does it need recapping because its old or because it hasnt been used?

Both, but primarily because it's old. All electronic components degenerate over time, some faster than others. Electrolytic caps (the kind used in power supply filters), wax paper caps and some of their equivalents such as early molded plastic caps (all primarily used for coupling and bypass throughout the circuit), are among the worst offenders. These should all be "shotgunned" as the first step in a restoration process, for it's a cinch that if they aren't already bad, they soon will be. Moisture is the key culprit in the decay of many parts, caps especially. As a rule, the more humid the environment, the shorter their life.

On the other hand, and perhaps paradoxically, long periods of idleness accelerate the decay of some parts. I call it "shelf rot." The more humid the conditions, the more impact "shelf rot" has. The older generation of electrolytic caps were perhaps the most notorious for going bad "on the shelf." As a rule, they tend to last longer with consistent use.

Again, please don't run this gear before it's overhauled, recapped and verified. With suspect and likely bad filter caps, you're risking very expensive power transformers, at the very least. Bad coupling caps in the amplifier output stages will put the output tubes and output transformer (more very expensive parts) at risk. By the same token, bad caps elsewhere in the circuit can cause the destruction of other parts. And caps aren't the only things to be verified.

Every transformer and choke should be tested and verified. Transformer and choke windings sometimes open and sometimes short out. Resistors should be checked, for they may open or, in the case of the older carbon composition resistors, they may drift off value. The older they are, the more likely this will happen.

As for caps in general, three things can go wrong. They can open, they can go "lossy" or "leaky" due to dielectric degeneration, or they can simply short out. Disc ceramic caps usually cause few problems (older tubular ceramics, which look somewhat like resistors, may be another matter).

There shouldn't be any mica caps (the older ones look like dominoes) present anywhere, except perhaps in your Fisher tuner (and based on my experience with Fisher gear, I'd expect to find ceramic caps there, instead of micas).

Time was when we used to consider mica caps "immortal," but we know better now, so any domino mica caps should also be checked (you likely won't have to worry about any dipped silver mica caps that may turn up).

And speaking of your Fisher tuner, its IF transformers may be among a large number of transformers subject to "silver mica disease."

I hope this helps. It is pointless (and unfair) to attempt to minimize the job you have in front of you. On the other hand, if you want an ideal clinic to learn tube electronics restoration from top to bottom, you certainly have it, but once again, you'll need a good and experienced hand to guide you along and explain things along the way (for you'll find PLENTY of questions).

Again good luck, and best regards--

Larry

Id really like to use this radio several times a week but after ready this post ill hold off. Looks like i need to find someone knowledgeable in KY and do some alot more research. FWIW the inside of the fisher before i cleaned it(not that it needed any cleaning).

At least it looks unmolested. It looks as if no slop-shop jackleg or twang-and-bang tube roller got in there and monkeyed around with it. You won't have to worry about locating and undoing someone else's mistakes, and that puts you one step ahead of the game.

If it's this Fisher tuner you want on duty first, it's a good place to begin. It may present you with fewer truly serious issues than the other gear, especially the power amps. The recapping shouldn't be extensive. The power supply filters and a handful of tubular caps are the only prime suspects; most of the caps are disc ceramics (I see one dipped silver mica and two that look like dipped film caps). All of these will likely pass muster.

Those two black molded plastic tubular caps at the back of the chassis, near the AC line input, are involved with the AC line. They may explode if they fail, and they MUST be replaced with true (AC-rated) safety caps.

As I suggested earlier, your best bet for qualified hands-on help might be your local ham radio club. Scout carefully, wherever you go and whoever you talk to, and be patient.

Again, best of luck, and keep us posted.

Larry

RC, wish I was around the corner from you as this would be a great project. Take Larry's excellent advise, and don't be in a hurry. You have come to the right place for honest and technically mature information (we've been around for a while).

Many recommend Terry DeWick, in Knoxville TN. But I just checked his website - his backlog is currently 45 days...