I need help with finding out what resistors i need to put on the circuit board. had a few fuses blow and i replaced them and it didn't solve the problem. after further inspection i noticed two resistors were blown. JP 1 and JP 2 were blown. i get a little sound coming out of the sub but no where near what it used to. My question is does anyone know what resistors go in those locations? i can see half of JP 2 resistor, so i know what to get for that one. However JP 1 resistor is burnt up pretty good and don't know what kind of resistor it is unless its the same as JP 2. does anyone know and if so where i could get them? Also can i by pass them by maybe using the speaker terminals? thanks
Have you tried contacting Sunfire and parts express? Sunfire should be able to tell you the values of both and if they can't send you new ones, parts express or parts dealer ought to be able to help you. If these are 1/2 watt or 1/4 watt resistors, Radio Shack might carry them.
F1 and F2 are basically a 0 Ohm link in the guise of a resistor.
I have a Mk II that is dead in the water with most of the hexfets (IRF640) blown and 1 of each pair of the output drivers...but while the guy I got this off sauys its never been in for service (im in SIngapore) it looks like it has non original parts in it.
could someone perhaps confirm the output drivers as they seem to have been replaced at one stage due to the parts being different form what I found online. The originals I think should be 2SA1302 / 2SC3281 but the ones installed are 2SA1934 / 2SC5200. The rest of the parts seem to be original. but if you can also confirm R8 and R72 values as they are different and I think should be the same. respectively they are 27 and 52 ohms.
Im also trying to convert this input power to 230VAC fromm the original 120VAC .. any ideas... Im thinking the bridge rectifier needs some reconfiguring ... maybe to get full instead of what looks like 1/2 wave?
IF you are still having difficulty with IR parts, call or email them with the stamp on the device. They should be able to tell you just what it is. I built HexFets for quite a number of years and am glad I don't knowingly own any!
You can look up a cross reference for the IRF640.....I think they may actually be original. Carver used IR parts in some of his SunFire pieces.
As for repowering? I'd offhand recommend a transformer. The 1/2 wave to full wave idea doesnt cut it.