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Fisher TA 600 Restoration "under the hood" Pics

NYListens

NYListens

CBGB & OMFUG
Ok, a few nights ago I started to re-cap my Fisher TA-600, I thought I would take some photos along the way and share my work. You can see how tight some of the section are:

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In this picture you can see the orange drops that I have put it and the one lytic I changed so far on top. You can see half of the coupling caps are white:
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These are the old ones and are not original. The were put in by someone who did a somewhat sloppy job soldering them in. They just wrapped and soldered without cleaning or removing the old solder and leads. Next to the old white coupling caps, you can see the ceramic wire wound resistor I replaced. I had to put two in series, as the only one I could find was 10ohms less than spec. So I put a 10ohm one right after.

This is the unit that has its rectifier tubes arcing. So I will slowly bring it up on the variac after I have replaced all the coupling caps and see how it works. If I need to, I will replace all the lytics too.
 
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Good luck. :thmbsp: I like my Fisher 600 a lot, & would be using it now, if I didn't find that McIntosh MX110. Hmm, I wonder how it would sound, running the Mc into the Fisher's amp, pretty killer I bet. :naughty:
 
It came alive tonight. I have quite a few more caps to go. Nevertheless, I brought it up on the variac tonight and the rectifier tube is no longer arcing, the radio worked and it sounded sweet through the aux with a cd player pumping into it. I'll try to get some additional photos up over the weekend.
 
Getting close to finished. I redid one of the lytic cans as it was leaking fluid underneath. You can see I used two terminal strips with a 22uf cap for the 20 ufs and a 39uf for the 40ufs. It is hard to find exact specs as original, but you can find well within 20% in most applications without breaking the bank. You can compare the original configuration with everything running to the can in the picture of the prior post.

Only one channel is really working at the moment. After working through the re-cap, I realized that Fisher had used some 25uf lytics as coupling caps on a two of the 12AX7s and the two 7199s. I wonder why? You can see my replacements (22uf instead of 25) for them which are the tiny blue lytics next to the large orange drops in the photo. If I work on this model again, I may look to find some sort of film cap with close specs instead.

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Ok, I have not replaced almost all of the caps (around 30). I can't get one of the channels to work. I will have to do some troubleshooting later. It also seems that the middle 12AX7s aren't glowing. These are the pre-amp tubes for the phono and tape stages. Oh frustration. :gigglemad The last two Fisher receivers I worked on, worked like new once all the caps and some tubes were changed. This unit has almost all new tubes.
 
NYListens said:
Ok, I have not replaced almost all of the caps (around 30). I can't get one of the channels to work. I will have to do some troubleshooting later. It also seems that the middle 12AX7s aren't glowing. These are the pre-amp tubes for the phono and tape stages. Oh frustration. :gigglemad The last two Fisher receivers I worked on, worked like new once all the caps and some tubes were changed. This unit has almost all new tubes.
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Doesn't it just figure that there would be a simple explanation??? I spent the last hour painfully going through the signal path with my scope. Tracing the signal from the speaker output to the output tubes and back and back. I finally get to the pre-amp tube stage and I need to shift things to get the scope probe in. I go to move my CD player and I notice that the patch cable is disconnected from one channel. :bash:

Now I know I had checked that last night. So perhaps there was a bad cap I switched out today, but man it is always the simple things that you mess up. At least I had fun with the scope.

I have to now check out the phono stage and the pre-amp, for the tubes are not illuminating at all. Thank goodness it is at least working with a CD player through the Aux and of course it sounds very nice.
 
Ok, I now have to clean and polish the unit, but at least she looks great under the hood and now sounds like new. Nothing like that warm sound of a vintage Fisher tube receiver.

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You can barely see the glow of the tubes:
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Congratulations! Nothing sounds sweeter than something you've brought back to life with your own hands.

Just a small caution, though. I would be careful not to get too aggressive in polishing the chassis. Think "clean", not "polish". It's not just that you can remove the lettering, but if you remove all of the cadmium plating, the chassis will rust. Plus, cadmium is toxic if you roll around in it too much!:D
 
Fisherdude said:
Congratulations! Nothing sounds sweeter than something you've brought back to life with your own hands.

Just a small caution, though. I would be careful not to get too aggressive in polishing the chassis. Think "clean", not "polish". It's not just that you can remove the lettering, but if you remove all of the cadmium plating, the chassis will rust. Plus, cadmium is toxic if you roll around in it too much!:D
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Thanks. I appreciate the word of caution. Believe it or not, I actually washed off my other Fishers with dish washing soap and water and a garden hose (I let them dry for days [3 at minimum] before I even thought of putting any electricity back in) and then I used a little Flitz on them to polish the surface a bit. I may just use a little Windex and Flitz on this one because it isn't bad. I usually apply some high quality auto wax onto the chassis to protect it from rust and finger prints. The transformers will be treated with a naval jelly treatment, followed by a light rust oleum spray. This is what I did on both my 500B and 500S and they both look great considering what they did look like. The 500S has some pretty freckling. The 500B had a few real serious rust spots, which I treated with naval jelly and then some flitz. I am sure I stripped those spots way down, but it was either do that or let the rust spread.
 
Wow. Great work.

Nothing better than vintage Fisher tube receivers.

Congrats.

Mark (aka Snade)
 
Snade said:
Wow. Great work.

Nothing better than vintage Fisher tube receivers.

Congrats.

Mark (aka Snade)
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Hey thanks. It is always a bit thrilling and sad when you finish it though. This is my third and I have enjoyed each one. I will probably wind up selling two of them :tears: so I can afford another project. I would like to work on a 500C, 400 and either of the 800 series at some point. However, Next I will go back to my 500B and swap out the ceramic coupling caps for some orange drops and a few other tweaks I have learned in here, as the 500B I use all the time and plan on keeping as long as I can.
 
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