Mr. Babin and Mr. Bezjak......

[shagone]

Originally posted by junglejuice



Boy that must be an old amp if it is pre HD as the HD's were very early 90's as I had a Punch45 HD and that was around 1993-4.....

yep it looks pretty old! i tested it and found that one channel works fine but the other channel has a bad fet (buz102) and a blown internal fuse. then i think i broke a .2 ohm large resitor from the board when i tried to pry the fuse out. oops! the fuze is a 6 amp 32v short fuse. anyone know where i can find those relatively easy? i think it was made by Little Fuse?

[Perry Babin]

It's an AGA 6 most likely. Try Autozone. If you are going to have to order the resistor and FET, order the fuses from the same distributor. Mouser is a good choice if you don't have much to order.

[shagone]

Originally posted by Perry Babin
It's an AGA 6 most likely. Try Autozone. If you are going to have to order the resistor and FET, order the fuses from the same distributor. Mouser is a good choice if you don't have much to order.

i already ordered the fets and i'll try autozone for the fuze. as far as the resistor goes, i have some 3 watt .15 ohm available. the one i broke off measured .2 ohms. will the .15ohm be ok or will i need to change all of them to .15 in that case? most amps i've seen have large .1-.15 ohm resistors anyways. maybe my reading was off on the existing resistors??

[Perry Babin]

What was the color code on the one you broke?

I seem to remember at least one series of punch 75 that had 22 ohms near the outputs but I think those used BJT outputs. I don't remember any punch amps with 0.2 ohm resistors. It's likely they are 0.1 ohm. If so, the 0.15 would be OK temporarily but you need to replace both of them if they are used with transistors that are operating as a parallel pair. If the amp works, you should replace the 0.15 ohm resistor with the correct resistor before you put it back into daily use.

[shagone]

Originally posted by Perry Babin
What was the color code on the one you broke?

I seem to remember at least one series of punch 75 that had 22 ohms near the outputs but I think those used BJT outputs. I don't remember any punch amps with 0.2 ohm resistors. It's likely they are 0.1 ohm. If so, the 0.15 would be OK temporarily but you need to replace both of them if they are used with transistors that are operating as a parallel pair. If the amp works, you should replace the 0.15 ohm resistor with the correct resistor before you put it back into daily use.

Thanks! That all makes sense. i'll check the color code in the next couple of days and i'll look it up and post my results.