fisher1
New Member
Hi, This is my first post here. I just bought a fisher kx200 and km60 from a friend for the price he paid at a garage sale....$10.00. I have been involved with tube guitar amps and thought this would make a great project. There is no sound like tube sound. I have read through many threads and have learned alot. I would like to thank Adpopulum for his indepth documented rebuild of the kx200.
The km60 seems to work well...fired it up with a variac and pluged it into my Eico amp. It seemed to pull in stations quite well. It has all the fisher tubes..all original. I will be replacing the rectifier and all electrolytic caps soon. I read about the RS rectifier part# 276-1181. So I will use that.
Now the kx200 is another story. It has black tar that has leaked out of the power transformer and also has an "added on" 100r 25watt resistor inbetween the power transformer and the first sd1 and sd2 diodes? (see picture) All the voltages from the transformer seem to be low due to the resistor.I fired this amp up using a variac and found that the voltage at the first cap is 367v. The schematic reads 405v. Probably due to the resistor. Does anyone know if that was to save the output tubes from the higher voltage and prolong tube life?
One of the output tubes is bad and the other is marginal should I go with JJ's so they fit in the cabinet? Any tips on cleaning the chassis? and faceplate? Also correct me if I am wrong, the C1 cap is not grounded, the one with the paper on it?
Do most of you replace all the can caps? or let them ride if they test good? Are their any other resistors I should change? Or any other parts that need replacement(will replace the diodes,all electorlytics under chassis and clean all pots). Any other suggestions are welcome.
Thanks for your time.
The km60 seems to work well...fired it up with a variac and pluged it into my Eico amp. It seemed to pull in stations quite well. It has all the fisher tubes..all original. I will be replacing the rectifier and all electrolytic caps soon. I read about the RS rectifier part# 276-1181. So I will use that.
Now the kx200 is another story. It has black tar that has leaked out of the power transformer and also has an "added on" 100r 25watt resistor inbetween the power transformer and the first sd1 and sd2 diodes? (see picture) All the voltages from the transformer seem to be low due to the resistor.I fired this amp up using a variac and found that the voltage at the first cap is 367v. The schematic reads 405v. Probably due to the resistor. Does anyone know if that was to save the output tubes from the higher voltage and prolong tube life?
One of the output tubes is bad and the other is marginal should I go with JJ's so they fit in the cabinet? Any tips on cleaning the chassis? and faceplate? Also correct me if I am wrong, the C1 cap is not grounded, the one with the paper on it?
Do most of you replace all the can caps? or let them ride if they test good? Are their any other resistors I should change? Or any other parts that need replacement(will replace the diodes,all electorlytics under chassis and clean all pots). Any other suggestions are welcome.
Thanks for your time.