Fisher 500C

[cspyon]

Hi
I'm looking to buy one one of these days.
Any advice on what I should look for in this vintage unit? Do I look for an restored one or unmolested one in good working condition?
Thanks for your feedback.

 

[hugh811]

500C is a gem. Built like a tank, very good OPT, top quality original german capacitors.

Attention must be paid to the volume pot which has a loudness tap. Quite expensive if you have to replace it. If sound is not even between the left and right speaker, the first culprit would be the volume pot. Make sure that the sound is even and the volume pot is ok.

The filter caps are the next thing you should care about. low voltage filter caps are usually way out of specs; high voltage ones should be ok. But this issue can be fixed quite easily.

Revision and checkups are needed for any vintage gear, so you should be prepared to pay some hundred bucks extra for the revision (maybe more if you cannot do it yourself). Original transformers are also a must.

 

[cspyon]

500C is a gem. Built like a tank, very good OPT, top quality original german capacitors.

Attention must be paid to the volume pot which has a loudness tap. Quite expensive if you have to replace it. If sound is not even between the left and right speaker, the first culprit would be the volume pot. Make sure that the sound is even and the volume pot is ok.

The filter caps are the next thing you should care about. low voltage filter caps are usually way out of specs; high voltage ones should be ok. But this issue can be fixed quite easily.

Revision and checkups are needed for any vintage gear. Original transformers are also a must.

Thanks for your reply.
This is the one I'm looking at now, which the seller said restored. What do you think, based on what you just pointed out?

 

[hugh811]

I can see some critical caps and the rectifier have been replaced. But nobody can tell if it is “properly” done without a throughout checkups, measurements and some listening. The volume - and on/off pot seems original but i cannot tell if there is a problem with it.

Esthetically speaking, i will not use radial lead type capacitors for that kind of project. But again it is a personal taste, because I would carefully buy replacement parts for this 500C, not what i currently have in hands.

 

[hugh811]

Make sure that all tubes are there. There are many of them in this amp, especially small ones for radio section. Even if you don’t use the radio features, the tubes must be there, because they are part of the whole schematic.

 

[hugh811]

List of tubes (what brand, condition …) should be specified because these tubes count heavily in the final price. Upgrading tubes is very expensive, especially 12ax7 and the power tube quad.

 

[cspyon]

....Esthetically speaking, i will not use radial lead type capacitors for that kind of project...

Hummm, I see only one there. Are there any more? By the way. I see several Teapo caps. Are they good?

 

[cspyon]

List of tubes (what brand, condition …) should be specified because these tubes count heavily in the final price. Upgrading tubes is very expensive, especially 12ax7 and the power tube quad.

12ax7 are Telefunken and Mullard
7591 are Sylvania. All test strong, according to the seller.

 

[larryderouin]

There's 5 or 6 Radial Electrolytics. There are also some axial's that must be replaced.

Pioneer has it's shoot on site transistors, Fisher has "SHOOT ON SITE" capacitors. The 1st two are axial 4.7uf and lower. Rubber insulators on both ends bulging and sometimes just hanging on the leads. Brand name FRAKO & DUCATI.

Bunch of Epoxy covered Film capacitors (commonly called "DOG TURDS") The hard shell breaks down and flakes off, or the leads separate from the film stack internally, causing intermittents. These caps are either BLACK or Brown.

 

[hugh811]

Hummm, I see only one there. Are there any more? By the way. I see several Teapo caps. Are they good?

Radial lead cap looks like this. Basically it is dedicated for pcb (printed circuit board).

 

[hugh811]

In a vintage tube amp like 500c, originally there is none of them (radial lead caps).

I prefer axial lead capacitors which look like this.

 

[hugh811]

12ax7 are Telefunken and Mullard
7591 are Sylvania. All test strong, according to the seller.

It makes sense.

 

[hugh811]

500c deserves better caps than Teapo.

In brief, 500c is a gem. I would grab it and pay a good price if volume pot and other pots are good, with all strong vintage tubes (not new production) and all transformers are original.

 

[cspyon]

There's 5 or 6 Radial Electrolytics. There are also some axial's that must be replaced.

Pioneer has it's shoot on site transistors, Fisher has "SHOOT ON SITE" capacitors. The 1st two are axial 4.7uf and lower. Rubber insulators on both ends bulging and sometimes just hanging on the leads. Brand name FRAKO & DUCATI.

Bunch of Epoxy covered Film capacitors (commonly called "DOG TURDS") The hard shell breaks down and flakes off, or the leads separate from the film stack internally, causing intermittents. These caps are either BLACK or Brown.

So, this ' restoration' that the seller mentioned doesn't look like a quality job. I'll think twice about this one.

 

[cspyon]

500c deserves better caps than Teapo.

In brief, 500c is a gem. I would grab it and pay a good price if volume pot and other pots are good, with all strong vintage tubes (not new production) and all transformers are original.

Thanks for your good advice.
I'll not buy this one. I would rather buy one in good original condition, fully serviced by a technician.

 

[dcgillespie]

It also looks like a number of caps were simply left in place and bypassed with a new cap, and other caps needing replacement weren't addressed at all.

Dave

 

[cspyon]

It also looks like a number of caps were simply left in place and bypassed with a new cap, and other caps needing replacement weren't addressed at all.

Dave

Thanks for confirming the ruling of other gurus ahead of you! I have decided not to buy this "restored " unit.