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My 800c restoration

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Excellent job and even more excellent presentation. I usually get so excited on my projects that I forget to take pictures like this.

Cheers,

David
 
What are your opinions on the SDS board mod? I bought one but decided to leave it out and let Mark Wilson do his magic and keep my 500c basically stock.

I have another 500c that I would like to restore and will most likely install it into that receiver. I have a few ideas about pimping this one out to look better also.

It looks like yours turned out to be pretty nice. Especially since you polished a lot of the parts.
 
Nice job.....I like to see this as the Fisher 4,5, and 8 series are true classics. My dad gave me a 500c when I was a kid...boy I wish I still had it. Your's is wonderful.
 
Yup, very nice photos of the incremental steps. I finished my 500B refurb last winter and only took pictures after I was done.

I should have done this on every step as you did : - ( -- The after photos of my 500B is below.

When you finish yours get a cabinet from Dan Crosby of Michigan. They really look nice on these Fishers!

Front-Top.jpg
 
Great restoration. The number of hours in a proper restoration is amazing, isn't it? Just out of curiosity what camera are you using?

You show a picture with the 24pf ceramic cap but do not show it replaced. This cap is often overlooked. I replace it with a 22pf 630v polystyrene cap I get from Justradios. He seems to be one of the few that has the higher voltage polystyrene's. I replace the 1000pf with a polystyrene or 0.001uf IC cap also.

Also note that the low filter is a coupling cap. This one is overlooked by almost everyone. I usually replace all four with IC polyprop or Orange drop 716 caps. This still does not address the ceramic pack in the tone controls. I still have not done it but replacing the pack (and a few others) with modern components would remove all ceramics in the signal path.

I am a getting to be a real nut about ceramics, sort of like tantalums in solid state equipment. There is a very revealing experiment with Audiodiffmaker software. If you download and install the software (http://www.libinst.com/Audio_DiffMaker_Minimal_Install.exe) and then run the file (http://www.libinst.com/SeriesCapTest.dyf) you can hear the grunge the ceramic is creating.

The one flaw in the SDS cap board is putting the load resistors with the power supply caps. This needlessly heats the caps up. I now keep the load resistors in their original locations or move them where they can dissipate their heat in the open.

As I am sure you have already noticed the SDS caps along with the EH tubes really gives the 500c a lot of punch. I have khorn speakers and the before and after was nothing short of amazing.
 
drew,

Did you still use the SDS board? How did you wire it if you left the load resistors off the board?

I have another quad of Eico Westinghouse single getter tubes I am going to use with this 500c. My first 500c uses a set of the same but double getters and sounds very nice.

Denny
 
The camera is a Nikon coolpix 950. Nice guess Falcon Eddy! It is only 2mp, but has great macro that lets it get very close, if you know what to do.
There are still a few more caps I may replace, I just first wanted to replace all the power supply caps, and electrolytic ones. I have replaced a few others that took longer to find.
As for taking pictures during restore, I always try to shoot stuff before I remove parts. That way I can go back and see what was where. Nothing worse than pulling a part, getting called for dinner and then forgetting where it came from etc. Learned from previous mistakes :-).

I wish I had one of those awesome wood cases, but don't have the cash for that right now. I may try to build one myself if I can find the time.
Not many options for the SDS board. I bought it as a kit with all the parts and assembled it myself. I have to say they give no details on actually wiring it up. That took lots of schematic reading to figure out where all the wires needed to go. And beware that bias resistor! It will likely not be a 5.6k (mine was 8.2k) Can't tell you how long I was searching for it by the colors for a 5.6k. I also saw no way to mount it using the tranny mounting bolts as it is so tight. Luckily there are vent holes right next to them, which moved the board away from the antenna connections. No holes drilled!
All in all I think it was a good choice to use the sds board as it killed many birds with one stone.

John
 
DENNYDOG said:
drew,

Did you still use the SDS board? How did you wire it if you left the load resistors off the board?

Denny
Click to expand...

I kind of cheated and used a board of my own design inspired by the SDS labs board.

The 15ohm is easy. Just leave it and run a jumper wire over to the SDS board (the other end is grounded to the chassis. The 470ohm resistors can be "long legged" and bent over to the chassis side (away from the caps), about 3/4" should be enough. Add heat shrink to the legs if you are paranoid enough. The 82kohm can be left and jump wired over to it. There are various solutions for the 2.7k and 22k 3w resistors, depending on the original wiring. I would not bother with the 1watt resistors. Hope that helps.
 
Very nice, I restored one of my Fisher 400's though it wasn't dead. Cosmetically I cleaned everything without much more than water. Small wet cotton rags flux brushes, soap and water on the face plate and lense paper on the glass. I used mostly OD 716P's for the caps. I've also been thinking about replacing the tone pecs with desrete components. I restored my Scott 340B in a similar maner, no fancy cleaners just meticulouse disassembly and damp rags.
 
Destructor said:
Very nice, I restored one of my Fisher 400's though it wasn't dead. Cosmetically I cleaned everything without much more than water. Small wet cotton rags flux brushes, soap and water on the face plate and lense paper on the glass. I used mostly OD 716P's for the caps. I've also been thinking about replacing the tone pecs with desrete components. I restored my Scott 340B in a similar maner, no fancy cleaners just meticulouse disassembly and damp rags.
Click to expand...


The above just about sums it up. That is the most efficient way to do this kind of thing. Orange Drops work very well unless you have space limitations. As for the dial glass, that is when you enter scary territory. I have been guilty of wiping clean, the dial glass of an HH Scott tuner many years ago. I am more careful now. Don't know about Fisher. But I am very cautious and do not use harsh chemicals and especially don't rub the lettering...
 
kvflyer said:
As for the dial glass, that is when you enter scary territory.
Click to expand...

Yes, I agree. I considered this the most risky part of my Fisher 500B restoration. Taking the glass off was very hairy. I tested cleaning on a serial number on the edge and then used 'SCreen Kleen' to clean the rest of the glass. The lettering was stronger on my unit than I thought it would be. Every unit is probably different.
 
Cut-Throat said:
Yes, I agree. I considered this the most risky part of my Fisher 500B restoration. Taking the glass off was very hairy. I tested cleaning on a serial number on the edge and then used 'SCreen Kleen' to clean the rest of the glass. The lettering was stronger on my unit than I thought it would be. Every unit is probably different.
Click to expand...

Certainly glad you had good results. I think that taking your time is the most important thing when doing restoration. Items from the late 70s, early 80s usually hold up great to cleaning. I use Fantastik or Formula 409 often with good results. Knobs clean up especially well with a tooth brush and the cleaner. I usually remove the set screw (and try not to loose it) when cleaning. That keeps them from getting rusty because moisture will remain around the threads for days. The air blast cans for cleaning computers work well to blast away the water if you don't have an air compressor or don't feel like digging it out.

For Scott chassis or bottom covers etc., I use Nu Finish car wax because it is not very abrasive. It will make aluminum that is just slightly dull and dirty look like new. Most aluminum has sort of a grain when you look at it from the press or whatever. If you follow that grain, the results are stunning. It will not however, remove pitting or corrosion...
 
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