[TV MAN]

I have been waiting to tackle this project. Now that you are done with your Fisher project Ron, I am going to start mine. The story of this is basically it is an Ebay find that I purchased to replace another 500c that I had since my college days at ITT in Indy. My original basically worked fine - until it got attacked by mice right under my nose! It was during a lenthley remodel of the house. It got moved out, and the mice moved in. My original intention was to take the 2 and make one. Well, I couldn't bring myself to knock my original in the head, so I am going to restore the one I purchased, then later I am going to attempt to restore my original. The 2 major problems are 1. The burned up power transformer, and 2. the shipping damage. I purchased it knowing the power trans was bad and almost all the tubes and knobs pilfered. Aside from that, she looked clean in in very good condition. 

I purchased a service manual and have been scrounging tubes. I do have a replacement power transformer (thanks for the lead Ron!) which ohms out good. I did an initial check on the output transformers, which both test ok. I am planning to order electrolytics  through Hayseed. I want to order high quality paper cap replacements. Any suggestions? Orange drops? I am assuming to replace all the small e-caps and those clear looking paper caps? How about the caps that look like an Orange drop except they are brown? Any others or anything else I should be aware from before ordering any parts?
   
   
   
   

[Ron Ramirez]

Tim - this should be a great thread!

The guys over at AK have stated that (what they call) the brown "dog turd" caps should always be replaced. Apparently they aren't as good as Orange Drops. Now, I have used yellow film as well as the hard case burgundy film caps from Mouser, which look like Chiclets (does anyone remember those?) to replace dog turd, clear, and EROFOL caps. I think I used all yellow film in my TA-600 and I'm quite pleased with its sound, even though the FM is Living Mono (no FM multiplex standard in 1959-60).

By "yellow film" caps, I mean the very same yellow film caps that many of us use in our vintage Philcos. I did not try to listen to my TA-600 prior to recapping it, but I have tried out a couple of my Fisher tuners prior to recapping and honestly, I can't tell the difference between old EROFOL and new yellow film or Chiclet caps. That tube Fisher sound comes shining through every time...

Ordinarily we try not to send anyone to other forums, simply because folks come here for the answers and we try to provide them when we can. In this case, however, I strongly suggest that you spend some time over at AudioKarma in the Fisher section, studying the IBAM and IBBA modifications. You should choose one or the other, and incorporate it into your 500C restore. Either circuit will allow you to properly setup the bias of the 7591A output tubes, prolonging their life. Your Fisher will thank you.

Then, of course, come back here and incorporate your added knowledge into this thread.

There are a few "dog turds" in the multiplex decoder that will require replacement. The MPX decoder also has a 1 uF electrolytic which should be replaced with a 1 uF, 350 or 400V film cap. The film cap is much larger, yes, but will last much longer.

[Arran]

I'm not sure about the clear capacitors, they used a lot of those in German radios for the 1950s and 60s but I think that they were plastic film and intended to be a substitute for some mica caps, polystyrene film possibly. The voltage ratings are not as high as either mica or most paper caps so they only used them in some specific locations, the rest they would use those black Ero caps with the brown paper labels which definitely need to be replaced. The mustard coloured caps with the ceramic coating were a Phillips product, those are usually still good, they are not paper inside, I would leave those unless the unit still has a fault. Sprague came out with the "Orange Drops" back in the 1960s, and whilst they were some of the best capacitors available in their day, and still are good, they continue to have a cult following and are priced well above where their equally good competition is priced because of it. In spite of what the myth followers believe they are not infallible, no capacitor brand is, if they were in situ in a piece of equipment I would not replace them without a reason, but there isn't much reason to choose them over something like Panasonic brand caps for replacing Aerovox wax caps for example. One cap that I would keep tabs on are the ones in the AM and FM IF cans and discriminator transformers, those appear to be of the Miller/Automatic K-tran style cans with the cheap mica sandwiches in the bases, if the set seems deaf on either AM or FM, or less selective, those are worth investigating unless Fisher cans are different then the typical ones.
Regards
Arran

[Ron Ramirez]

The IF cans in Fisher receivers and tuners were made by Automatic, so yes, there is always a possibility of a bad mica sandwich in an IF can. But let's not cross that bridge unless we have to. Go ahead, recap, install either the IBAM or IBBA mod and see what you have from there.

I've only had one problem with a K-Tran in a Fisher so far (knocking wood), and that was a broken wire in an FM limiter coil in my 100-T Coronet tuner-preamp. But these things are 50+ years old now so they are bound to have some trouble sooner or later.

[TV MAN]

I found a lot of information at Audio Karma. Almost overwhelming. It looks there are a lot of different rebuild "kits", capacitor boards, and advices. Gonna pause on this project and do some serious reading before I proceed. I want to keep it simple and only do the upgrades that will make the most difference. I do want to save unnecessary wear on the output tubes and make them last as long as possible. Any known source for knobs? Thanks for the information so far.

[Ron Ramirez]

Any known source for knobs?

Not really. They are highly sought after, and the prices range from very high to ridiculous. I've never asked Mike Koste if he has any Fisher knobs; I need to. I have a circa 1961 500-S that is missing some knobs; they are different than your 500-C knobs and appear to be much harder to find.

This is probably why your 500-C that you bought from the auction site was missing all of its knobs. There's gold in them thar knobs! And the missing tubes - 12AX7 prices are crazy, just crazy. 12AT7 prices aren't far behind. And these are not rare tubes! Not to mention the 7591A outputs...

Just recently I purchased a Fisher Ambassador tuner, a pull from a console. The seller included a bag with all of the knobs! That wasn't even mentioned in the auction ad. Great bonus! I hope to eventually own an 800-B and *maybe* a 500-C or 800-C; if I end up with one which has missing knobs, I'm pretty well set now. Or I could use them as (incorrect) replacements on my 500-S...

[TV MAN]

I'm not surprised to hear that about the knobs. I see plenty of the gold "ends", but rarely any knobs. I do have a full set from my original I can use while I search for a source. For this project, I have a good set of (mostly) original 12AX7 tubes, and some others that are made by Mullard and Amperex. I also happen to have a couple decent sets of output tubes, plus an original set of Fishers. I bought a bunch of tubes back in the early 1990's when I could buy directly from Westinghouse for pennies on the dollar.  I did stumble across these: https://www.ebay.com/itm/NEW-ORIGINAL-Fi...1438.l2649

   

[Ron Ramirez]

Tim

Those knobs are for early Fisher solid state gear. They are different from the 500B/800B/400/500C/800C knobs.

And at an asking price of only $15.95 for just one knob, this will give you an idea of what the 1962-69 Fisher tube gear knobs are going for. (In other words - higher than that.)

[TV MAN]

Found this. Any thoughts?

https://www.ebay.com/itm/Fisher-500-C-Va...0011.m1850

https://www.ebay.com/itm/Fisher-400-500C...0009.m1982

[Ron Ramirez]

You might be more satisfied with this instead.

http://metalbone.net/fisher.html

* DISCLAIMER: I HAVE NO AFFILIATION OR EXPERIENCE WITH THE METALBONE KITS *

The Metalbone kits get a lot of respect at AK. (I keep mentioning AK because there are some solid Fisher gurus over there, from whose writings I am still learning.)

Your first eBay link appears to be from a guy who calls himself the "Fisher Doctor" or "Fisherdoc". From what I read, some people like his kits, others do not. Again, NO AFFILIATION OR PERSONAL EXPERIENCE with his kits.

Your second eBay link - I personally think that $185 for about $20-30 worth of parts is ridiculous. But then again, I prefer to do my research, see just what I need for replacement parts as well as parts for sensible modifications such as IBAM or IBBA, and then buy the parts from Mouser or Digi-Key. Sure, it takes longer to do the research, but I feel the end result justifies the time spent.

* Please note: I am not being critical in any way, so please do not read anything into the above. I'm just trying to help.

IBBA mod discussion:

http://audiokarma.org/forums/index.php?t...on.601583/

EFB mod:

http://audiokarma.org/forums/index.php?t...rs.539265/

another 500C discussion:

http://audiokarma.org/forums/index.php?t...er.803665/

[Arran]

Fisher branded 12AX7s are probably near the moon, but Fisher didn't make tubes they just rebranded ones made by someone else. Mullard, Phillips, Amperex, and Valvo 12AX7s are all the same, but for whatever reason, much like with the Sprague orange drop caps people seem zoomed in on the Amperex and Mullard ones just because of the water based ink labels. You can use Russian/Soviet 12AX7s, the Fisher won't know the difference, or good testing used ones of any brand.
  If you want to save some work, and some money, leave the mustard coloured Phillips caps alone, those rarely go bad, but stick with replacing the dog turds and the electrolytics. I'm not sure about the transparent ones, I believe that those are plastic film caps, possibly polystyrene or polypropylene, so they might be all right. Some guys on various forums shotgun everything when there is no need to, guitar players have a similar mindset when it comes to tubes thinking that it makes their amp sound better. Those parts kits look like a ripoff to me, just generic yellow film caps that you can get anywhere, and I don't know about the electrolytics but if they are off branded stay away.
   I'm actually surprised that nobody is making repro Fisher knobs of at least some types, I'm also surprised that they were mad specially for Fisher and were not simply sourced off the shelf from a plastics molding firm like Kurz Kash or Amphenol. What makes them so special, the colour or the trim?
Regards
Arran

[Ron Ramirez]

Ditto the Russian/Soviet 12AX7 tubes, I haven't tried any yet but I'm quite satisfied with the 6P14P-EV output tubes in my TA-600 which replaced the original, worn out 7189s.

Regarding Fisher knobs. As with vintage/antique radio, every hi-fi/stereo manufacturer used their own knobs. Vintage Fisher units are popular, and in high demand, so the parts such as knobs sell for crazy money. The brass knob caps are being reproduced by at least two outfits who sell on the auction site, but no one is reproducing the actual knobs. Hmmm...our friend Ed at Renovated Radios could probably make some $$$$ reproducing these?

Why are the knobs so expensive? Supply and demand. Fisher didn't make as many units as Philco. Fisher was expensive when new, thus sales were limited. Until Fisher began the conversion to solid state, they were a competitor with McIntosh. Can you smell the money yet? From perusing old Allied catalogs, it appears that Fisher was always priced a bit under McIntosh. And then there were other players such as Harman Kardon, H.H. Scott, Marantz, Bell, Bogen, and even our old friend from antique radio days, Pilot. Eventually, Bell and Pilot went out of business; Bogen quit the hi-fi/stereo game to concentrate on professional audio, Fisher products became cheaper (and cheapened) after the sale to Emerson and really went downhill after they were sold to Sanyo. By then Japanese manufacturers such as Pioneer and Sansui had filled the void left by Fisher and Scott. Through it all, McIntosh remained (and has remained) the product for the well-heeled. But I digress.

[TV MAN]

I have to agree on the 2nd kit I posted. I thought it was high priced also, but did include the e-caps. The 1st kit sounds a little better, but I am going to do a little more reading and studying before I hit the trigger. Concerning the tubes, back in the early 90's, with absolutely no advice available, I would often re-tube something like a radio or TV. Most of the time it would improve the performance considerably, and at that time, tubes were fairly cheap. My 1st Fisher was no exception and it got re-tubed with the Westinghouse tubes, made in the USA. Aside from the lousy stereo reception, it worked flawlessly. I tried a set of 7025 tubes in a Dynaco preamp that I re-tubed and they (made in Yugoslavia) were terrible. Noisy. So I put 12AX7s back in. I have found most of the tubes I pulled (I seldom throw anything like that away) from the Fisher and Dynaco. Most test strong and balanced, a few not so. I tried a Russian 12AX7 JJ, and it tests on the low end of the spectrum. Probably OK in something that a lot of gain isn't needed. Anyway, thanks for the advices and help so far! Keep it coming!

[Ron Ramirez]

From what I have read, JJ tubes aren't the greatest. On the other hand, Electro-Harmonix and the new Tung-Sol (Russian made) tubes seem to receive positive reviews from folks.

You probably can't beat NOS USA tubes in any event, but NOS USA audiophool tubes such as 12AX7, 12AT7, and just about any hi-fi/stereo audio output tubes made in the USA command premium prices these days.

I would expect Yugoslav tubes to be lacking in quality. Remember the Yugo?

Nothing wrong with Westinghouse. If anything, you're ahead of the game there.

My 500-B has a mix of two JJ 7591 and two Electro-Harmonix 7591 tubes. Oned I get around to restoring that receiver, I'll probably bite the bullet and replace all four 7591s with a matched quad of EH tubes. They're a bit cheaper than the Tung-Sol reissues, but have a better reputation than JJ.

[Ron Ramirez]

Trivia:

Tim, did you know the company behind Electro-Harmonix, the Tung-Sol and Mullard reissues and a few other tube brands, is an American company even though the tubes are made in Russia?

Mike (morzh) mentioned a very interesting link in my Fisher TA-600 thread about New Sensor and the man behind the company, Mike Matthews who seems like quite a character.

https://www.stereophile.com/news/052206t...rHc5SHc.97