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Fisher 500b help, please.

NYListens

NYListens

CBGB & OMFUG
Well I finally won a tub receiver on e-bay. It is in the mail and should be here in a day or two. I am eager to start re-capping it and the rest of the restoration process. However, I have read on here that there are restoration packs available from several sources. These packs seem very expensive for what you get. I assume all the caps and everything else would run $30 at most. Is there a list anywhere available of what you need to replace? Does it make sense for me to order one of these with full instructions, as I have never done this before? I have had some experience soldering, but only have basic electronic knowledge, such as what most of the components do and what their symbols on a schematic are.

I don’t know what other modifications need to be made, other than reading that the rectifier bridge needed to be replaced (I don’t know what that is.)
 
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I bought one of those kits that includes a circuit board that mounts under the power transformer. While the kit was high quality, I wouldn't do it again. The board is a VERY tight fit, and I had to make modifications and add extra insulation before I felt it was safe. Individual caps would have been easier to install.
 
IMNSHO.... The VTV kit isn't cost effective, nor do the "instructions", which are quite generic, make up for it. I only know this 'cause I rehab'bed a 400 for a fellow here in MA who'd bought the kit. I cannot vouch for anyone else's, though.

There are a couple of threads here that may be instruction enough, depending on your confidence and how careful you may be.
 
I think the Fisher has a selenium bias supply. That should be replaced and of course, the coupling capacitors to the outputs and probably the ones to the tubes before the 7591 outputs (12AX7?). I have one of those resto-kits and after reading and "sitting on it" I have no intention to put it into my 800B.

I will however tell you that I lifted the cathode connection in my Sansui 1000A and placed a 10 ohm resistor in series with each cathode. Makes an easy way to figure out the idle current for each 7591.
 
 
The restoration kits sold by ebay seller "l_metalbone" look like a good deal to me.... Yes, you can save a lot of money by sourcing the individual components from a supplier like Mouser or Digikey, but it takes a bit of knowledge to figure out what you need. Looks like he has actually put some effort into the instruction book that comes with this kit, which is really what you are paying for. I did a thorough rebuild of my 800C a couple of years ago... and would've welcomed a kit like this.
 
mhardy6647 said:
Well, I am hopeful that you'll try the search function yourself... :-) but in the meantime...

http://www.audiokarma.org/forums/showthread.php?t=140313&highlight=Fisher
http://www.audiokarma.org/forums/showthread.php?t=158807&highlight=Fisher
http://www.audiokarma.org/forums/showthread.php?t=140768&highlight=Fisher
http://www.audiokarma.org/forums/showthread.php?t=78700&highlight=Fisher
http://www.audiokarma.org/forums/showthread.php?t=106131&highlight=Fisher
http://www.audiokarma.org/forums/showthread.php?t=94896&highlight=Fisher
http://www.audiokarma.org/forums/showthread.php?t=89453&highlight=Fisher
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Thanks, I think I have read through each and everyone of those threads. There is a tremendous amount of really good info on them too. Unfortunately, I didn't find a list of components that was needed and the really good threads focused on other Fisher models.
 
I started pricing out the replacement capacitors on mouser and parts express, I can't believe how expensive some of them are. I think the kits may actually be a good deal.
 
how much is this resto-pack?

if you calculate each component to be replaced, it might be cheaper, but sometimes you can't buy just one of each, and power filter caps will be expensive.

while restoring it completely might be your long term goal, doing it one step at a time can be really fun and practical, too.

i would suggest that you replace:

- the selenium rectifier
- electrolytic caps including bias cap
- install cathode resistors
- signal caps

if the output tubes are newer production, it is very important that you lower the bias current. you do this by replacing bias resistor next to the bias cap (i would start at 2.7k and then go up while checking the current at the cathode resistor). also make sure that the tubes are matched pairs.

everything else is not as critical as the above, and you can do it later.
 
gogofast said:
how much is this resto-pack?

if you calculate each component to be replaced, it might be cheaper, but sometimes you can't buy just one of each, and power filter caps will be expensive.

while restoring it completely might be your long term goal, doing it one step at a time can be really fun and practical, too.

i would suggest that you replace:

- the selenium rectifier
- electrolytic caps including bias cap
- install cathode resistors
- signal caps

if the output tubes are newer production, it is very important that you lower the bias current. you do this by replacing bias resistor next to the bias cap (i would start at 2.7k and then go up while checking the current at the cathode resistor). also make sure that the tubes are matched pairs.

everything else is not as critical as the above, and you can do it later.
Click to expand...

I ordered the metalbone kit with photo instructions. I hope they are good. This is my first restoration and if it goes well, I will have a much better sense as to what needs to be done and perhaps can do it at a lower cost. However, when researching the caps I discovered that it can be very expensive to order one off parts. I thoroughly washed the chassis today and stripped, primed and put a coat of paint on the transformer bells and the larger transformer that can't be removed without taking off the wires. I am working on photos and will post a thread of steps as I go.
 
NYListens said:
This is my first restoration and if it goes well, I will have a much better sense as to what needs to be done
Click to expand...

500b was my very first restoration of any tube gear, too. one thing i'd advice, if you haven't done any soldering works before, is to make sure the soldering iron is hot enough and the contacts are solid. finishing the restoration and finding out later of cold soldering joints is pain in the ass:no:. good luck!:thmbsp:
 
gogofast said:
500b was my very first restoration of any tube gear, too. one thing i'd advice, if you haven't done any soldering works before, is to make sure the soldering iron is hot enough and the contacts are solid. finishing the restoration and finding out later of cold soldering joints is pain in the ass:no:. good luck!:thmbsp:
Click to expand...

Thanks for the advice. Luckily, I have soldered a fair amount of connectors. I am more worried about navigating through the jungle of resistors, capacitors and other various components. I also worry about over-heating the components I am installing.
 
NYListens said:
Good to know.
Click to expand...

I refurbed a Fisher 500B, with a lot of help from others on this site. The one piece of advice that I can offer is 'take your time' - No rush to finish as your 500b will probably outlive you.

Also, Replace 1 component at a time and then fire up the receiver and make sure it plays OK. this way if something is wrong you'll know exactly which component is faulty. If you replace 20 components at once and then fire up the receiver and it doesn't work - Good luck in finding the problem.

The journey is the fun part! - enjoy!:yes:

Front-Top.jpg
 
Cut-Throat said:
I refurbed a Fisher 500B, with a lot of help from others on this site. The one piece of advice that I can offer is 'take your time' - No rush to finish as your 500b will probably outlive you.

Also, Replace 1 component at a time and then fire up the receiver and make sure it plays OK. this way if something is wrong you'll know exactly which component is faulty. If you replace 20 components at once and then fire up the receiver and it doesn't work - Good luck in finding the problem.

The journey is the fun part! - enjoy!:yes:

Front-Top.jpg
Click to expand...

cut-throat, everytime you post your gorgeous 500b, mine gets so jealous and might even blow a few 7591's. :D
 
gogofast said:
cut-throat, everytime you post your gorgeous 500b, mine gets so jealous and might even blow a few 7591's. :D
Click to expand...


Yes, that is one of the finest looking Fishers I have seen on the web. I fear the chasis on mine is too badly soiled to ever make it look as nice as cut-throat's. It even has a nice sploch of rust on it, something I reduced with some naval jelly.
 
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