Solid State Guitar Amp Forum | DIY Guitar Amplifiers

Solid State Amplifiers => The Newcomer's Forum => Topic started by: cormacbrosnan on July 31, 2014, 05:44:42 PM

Title: Fender Champion 300 Amp Has No Sound
Post by: cormacbrosnan on July 31, 2014, 05:44:42 PM
Hi all!

I just joined today and was hoping someone could help me out.
About two years ago, my electric guitar was plugged into my Fender Champion 300 amplifier.
When I turned on the amp, the light was on but no sound came out when I strummed the guitar.
I went back to the switch and tried to turn off the amp. It was REALLY hard for me to push it in.
I forced it, however, and now the switch feels "loose" - perhaps broken.

What do you think the original problem was? What should I do about that and now my seemingly broken switch?

Thanks!
Title: Re: Fender Champion 300 Amp Has No Sound
Post by: DrGonz78 on August 01, 2014, 05:28:24 AM
There are many things the 1st problem could be, that include too many to list on a whim. Perhaps we address the 2nd problem first. When you turn on the power switch does the pilot light come on? The switch is either on or off. So it is either working or not and that will be the easy question to address first.
Title: Re: Fender Champion 300 Amp Has No Sound
Post by: J M Fahey on August 01, 2014, 08:00:31 AM
Agree and add: a switch is basically 2 metal contacts which either touch each other or not , and what keeps them together is the pressure of a small, relatively weak spring.
Usually you do not directly move the contacts but the spring.
Usually there's no problem with that, surfaces are clean metal and make good contact with each other even under feeble pressure.
BUT, sometimes metal contact surface gets dirty, rusts, etc. and contact becomes poor,which means it now has some higher resistance, instead of tenths of an ohm.
Now current passing through it creates heat, sometimes enough to melt plastic.
I guess that's what happened: plastic softened , switch  button "froze" (literally, as soon as softened plastic cooled off) and you had to push it hard to turn it off, probably tearing away that little plastic which got in the way.
And noiw the switch is loose or has some "play" .
Yes, first task is to get a similar one and replace it.

If this is the one:
(http://93.img.avito.st/640x480/838135393.jpg)

measure its size , basically the hole size and search an online catalog such as Mouser or Digikey for another one which fits in that cutout.

Should be relatively easy to find and definitely inexpensive.