Fisher 1960?

Hook them to + to 16 and - to g. You won't get the same reading at the transformer that you get from the speakers.

Larry
 
i did that.
+ to 16 and - to g and get point 7 ohms with no wires from the speakers connected.
actually i also tried it with them connected and got the same reading.

i tried at 8 and 4 i get point 5 ohms.
 
1.) Did you test the tubes?

2.) Clean all the controls? Including the "level" controls on the back.

have you powered the amp up at all? If not Use a variac or Dim Bulb tester (incandescent light bulb in series with the power cord. Search Dim Bulb tester in the DIY Forums) for the 1st power up, or you risk loosing a capacitor. If everything is fine (no smoke, arcing, fire, etc.) when you get to a 100W bulb, then hook it up to wall power. MAKE SURE speakers or a dummy load is connected to the outputs or you can lose them.

What are the "LEVEL" controls set at. Full clockwise? They are basically a second set of volume pots so that in case of a volume inbalance you can balance the volume at the back of the amp and then control the volume from the main volume control on the front. Put them at FULL CLOCKWISE or anti clockwise (which ever gives you the most volume.)

I get 1.4oHms on the 8 ohm setting on my 400, so what you're reading is the static reading of the secondary for the output transformers. I would think it's ok.

Larry
 
ok i was afraid of this.
here's what i found upon closer inspection on the bottom of the chassis.
i cannot solder to save my life and would be afraid to try on this.
what is that and would that cause me to have no output?.
 

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larry the controls on the back are set at almost full to the right.

every time i've fired it up i had speakers connected to it.
i was told when i got it they used it within the last 6 months so i did not think i needed to bring it up on a variac. maybe i was wrong. i just hope i didn't destroy anything.
 
if it's been brought up in the last 6 months you're more than likely ok. With the age of the unit (50years old) it's gonna need at least a recap.


Easy Fix. Get a Ceramic resistor that matches the oHms and Watt rating for the old one. Then Get a friend that CAN solder to solder it to the lower connection and the PIN 3 on the LEFT HAND TUBE. If he can clean up the corrosion on the Right side Tube, then it's possible to solder it to that tube. But they are connected thru pin 3 so either one is fine.

OR take it down to a AUDIO Repair shop/ TV shop and ask them to replace the resistor.

That's one problem . There may be more. TAKE A Couple of pictures of the underside of the WHOLE Chassis. Then we can spot potential problems that are glaringly obvious.


Larry
 
here's a bigger pic so you can see where that "white block" is in the chassis.
 

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Hey guys, there's a sort of schematic for SA-16 here if you've not found it yet:

www.quadesl.com/pdf/sa16.pdf

Looks like they've made some changes to the circuit but they are marked as such. The resistor off pin 3 of one of the 6CA4s in the power supply is marked 100 ohms. I noticed that the SA-16 circuit is very similar to the 30-A except for the latter only having one channel and using a single EZ81 rectifier. The 30-A uses a 100 ohm resistor off pin 3 of the EZ81 as well. It's marked as a 5W which drops the 390 V to 385 in the 30-A. The voltage on the B+ of the SA-16 is a little higher so maybe they use a slightly higher wattage rating on that resistor (7 watts?). Is it marked?
 
thered1
no there are no markings on that resister.
the brown one closest to the white is marked 3500 ohms 7 watts and the other one is 125 ohms 7 watts
 
It's either a 7W or 10W by the looks of it. Looks like the Origianl solder joint corroded off. Suggest new resistor, and connect to the other tube on pin 3. Then recap.

That's the same on that's on Yahoo/FISHER Group.
 
measure it with a VOM across the resistor. It looks like the 100oHm 7-10W resistor on the schematic.
 
Since it is no longer in the circuit you should be able to measure its resistance. Of course you'd want to unplug the unit and be aware of the very high voltages that may be stored in that particular area of the power supply. Though, if that is the 100 ohm resistor that's come loose then nothing should be charged. Then again, we don't know exactly when that connection was severed - if it came loose while you've been messing with it, it might indeed still be charged. You might want to read up on discharging capacitors just to be on the safe side.

All of this does make sense with regard to all of the filaments glowing but no output. The filaments are supplied by a separate winding on the power transformer and are not in the same circuit as the power supply resistors. If that is the first resistor in the power supply, you've got no B+.
 
Definately need a new resistor at minimum. If the resistor shorted, and before it burnt off, it could have over voltaged the can cap and or affected the down line resistors. You'll need to lift a side of the resistors around the other end of that resistor. They need to be tested OUT OF CIRCUIT. You can't get good reading on them when in circuit. Then test each one. replace any that show more than 10% over or under the resistance shown by either numerical markings or the color bands on the resistors. The can cap should be replaced also.

Larry
 
well i tested the speakers in the console and they all seem to work:banana:.

the more i look at the amp the more i think i'll let someone who knows what they are doing repair this. i'd like to get it up and running but i think i'll let it go the way she sits.
if anyone in virginia wants the whole console let me know other wise i'll put the individual pieces up on that site.
thanks for all the help and idea's but this is more than i'm ready for at the moment.
 
The OP decided to part it out.

The Amp and Tuner/pre are on the Auction site. The Cabinet/spkrs/turntable are going to a good home.

Larry
 
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