Biasing question

[Cody_S]

Ok I recently bought my rm100. Well I installed the tubes and started biasing them. I put my multimeter in tube 1 and I set it to the mv I wanted. Well I moved the red test point to tube 2 and it read.1. Well I then moved it to tube 3 and it read about 35.x. Finally I moved it to tube 4 and it read the same as tube 2. Are the tubes or fuses bad? This is my first time biasing an amp so any help will be greatly appreciated.

 

[KillTone]

Hey Cody:

Welcome to MTS!

Sounds like you are not adjusting the bias at each point. There should be 4 bias pots on the RM100 - one for each power tube. You need to adjust each one to the same level.

 

[Cody_S]

No I had it in the test point for each tube. But when I turned the thing to adjust the bias it didn't read any different.

 

[BigBrewtus]

Tried swapping fuses yet? Or swapping tubes in different positions?

 

[Cody_S]

No not yet. I was really busy yesterday. But i'll look at the fuses later today and if they're not blown ill try swapping the tubes to see if it changes. And i'll report back if I notice anything.

 

[Cody_S]

Someone said to set the half power switch to full?? How do I do that?

 

[KillTone]

There is no half power switch on a RM100.

 

[Cody_S]

Can you change the power thing on the left? It's currently at 120. What should it be at?

 

[KillTone]

Hey Cody:

That is a voltage selector for using the amp in other countries where their power systems are different from here in the US. 120 is the correct setting here. NEVER power the amp on unless it is set properly.

 

[Cody_S]

Ok thanks. I wasn't too sure on what it was supposed to be at. Now i'm going to check the fuses. Do they just screw out with a screwdriver or what? Thanks for the help so far guys.

 

[Cody_S]

Scratch the wuestion on how to take the fuses out. I figured it out lol. I think it's the tubes though. I looked at the fuses and they looked fine, no burn marks or anything like that. Then I switched tube 2 and 3 and now tube 3 isnt reading. When originally 2 and 4 werent reading.

Edit: I bought this used from guitar center, should it have some sort of warranty on it?

 

[KillTone]

Randall may help you out by my recent experiences with their repair shop have not been great. I would probably talk to GC and at least try to get a huge discount on some new tubes. They probably sold it to you "as is". Check your receipts.