Vintage Ampeg B-100 Bassamp fuse, where is it?

[WillyWP]

Hello.

I havre a solid state vintage Ampeg B-100 Bassamp which stopped working. I want to check the fuse but it looks like I have to open the enclosure to do so. Does anybody have experience doing this with this kind of amp? I want to avoid pulling off the metal corners fi possible. Thanks.

[52 Bill]

Welcome to the place.

I will assume that this is one of the '70s versions with black tolex and a silver front panel with 3 knobs?

There is a service memo dated October 1976 that states:

B100/G100 - Fuse Failure
Early models were shipped with a 3/4 Amp Fuse. It was later found under certain conditions this fuse would open prematurely. This fuse should be replaced by a Bussman or Littlefuse 3/4 Amp Dual Element (Slow Blo) Fuse. The fuse can be replaced by removing the four screws holding the chassis and sliding it forward until the fuse is exposed. Total disassembly from the cabinet is not required.

If the fuse has already been replaced with a slow blo or if it blows again, then you have a circuit problem with the amp and it will need to be serviced.

[WillyWP]

Thanks 52 Bill!

It is a '70s one with black tolex and a silver face.

I got it opened, and strangely there are two slots for fuses, but only one is in it. The filament looks intact, but I'm hoping if I go buy 2 new fuses and put them in maybe the amp will work again. I don;t want to spend the money to have it serviced if its possibe. Pictures below.

[52 Bill]

I got it opened, and strangely there are two slots for fuses, but only one is in it. The filament looks intact, but I'm hoping if I go buy 2 new fuses and put them in maybe the amp will work again. I don;t want to spend the money to have it serviced if its possibe.

That fuse holder doesn't look original to me, and the two sections look to be wired in parallel, so you only need one fuse in there.

Even though the fuse looks good, it may be open. The only way to know for sure is to test it with a meter. If you take it in to the shop where you can get a new one, they may be able to test it for you if you don't have a meter of your own.

[WillyWP]

Thanks again 52 Bill! I'll take it down to the hardware store to see what they say. Your help is much appreciated. -Willy

[WillyWP]

One more thank you for 52 Bill. I bought a new fuse, put it in, and the amp works great. Thanks so much. -Willy