[Joeztech]

Ed;

On restuffing electrolytic can capacitors, I did some of these for years but my hands have been affected by arthritis and so I quit doing those and have since gone solely with Hayseed replacements. My hands thank me!

I agree that the value of these vintage tube stereo units far outweighs the few dollars saved by restuffing or trying to reform questionable OEM capacitors. I also replace all the smaller axial lead electrolytics with new ones as you have done. It can solve tricky problems before you power up a unit the first time.

One of the things that can plague any of us is solder splashes, drips or small wire clippings getting into hard to see spots that later result in more problems. I generally turn a chassis over after installing new parts and give it a couple of raps against the table to dislodge loose items and let them drop out for going into the trash. I find that I have to go over a chassis multiple times before proceeding to apply power just to make sure I haven't done something really stupid!

Getting those soldered-in can electrolytic twist-tabs loose can be difficult. I have two soldering guns, both are Weller units, an 8200 N 100-140Watt and a D-550 240-325Watt unit. In some cases I have to use both guns at the same time in order to liquify the solder enough to remove excess or wick the excess away to facilitate removal or installation of new parts.

Good going!

Joe

[EdHolland]

Thanks Joe,

Good tips on the alignment - I may compare the methods you mentioned.

The Hayseed caps were definiteky worth it. Given the effort to remove and replace four cans in the 500C, I appreciated not having to cut open and restuff them.

IBAM is simple enough, and works nicely. The mod is completely reversible - I even left the old bias network components in place (disconnected) so that originality could be restored.

I had very littke idea about these specific units or anything about the HiFi products of the era. Restoring this unit has let me learn a lot, and appreciate the excellent quality of design and build.

Ed

[Phlogiston]

Some of the reproduction can caps were only rated at 65 deg C. Yeah, not even 85deg let alone 105. So in most cases I have avoided them BUT(!), I see that the sections in his are rated at 105deg C. Very good. The price isn't too bad. I could see that restuffing could save you about half, but cost you several hrs.

[EdHolland]

I took careful note of the cap ratings Russ. They meet or exceed the originals in temperature and in some cases, working voltage.

This one has been quite a spendy project - spread over several months. The further I progressed, spent time appreciating the design and constructuon, and read about it, the more it seemed worth doing properly.

Ed

[EdHolland]

Fun stuff today. I played with the new 7591A valves. While they were purchsed as a matched quad, the bias required for equal current varies between 19 to 21 V, (for 32 mA standing current) which is close enough to the maximum of 24 V available, and quite a bit higher than the original bottles.

They sound just fine and in appearance are very close to the old bulbs. Enjoyed a blast of different music whilst working on other things. I need to add the new dial glass and take a picture or twp to complete this thread.

Cheers,

Ed

[doc_zap]

Hi:
New member here with a question about the Fisher 500c. I just bought one and it arrived with a broken cable pulley on the variable tuning capacitor. I glued the hub back in, but slipped on installation and the string came unwrapped. Does anyone have an illustration showing how to re-wrap the control string onto the pulley?

[EdHolland]

The best I can do is take a picture for you.

P.S. if you haven't found it already, the service info and schematic is readily available on line:

http://www.fisherconsoles.com/non%20console%20manuals/fisher%20500c%2030001%2049999%20sm.pdf