ampage Tube Amps / Music Electronics	For current discussions, please visit Music Electronics Forum.

ampage archive

Vintage threads from the first ten years

Switch question

:

5/4/2005 9:44 AM

Switch question

I have a '64 Gibson GA-17 RVT that I'm currently rebuilding. It really hasn't been that difficult especially considering that this is absolutely the first electronics experience I've ever had. So, on to my question and I sure hope someone here can help me. The GA-17 has a rotary on/off switch. I like that it's rotary and I would like to keep it that way but I'd also like to add a standby switch. I know where in the circuit to add the standby but I'd really rather not have to drill another hole in the chassis for the switch. I'd like to have it as a part of the on/off rotary switch, like a on/standby/off switch. So what I need to know is if anyone knows if there is a 3 position rotary switch available anywhere and if so if you think that this should work. I really can't imagine why it shouldn't but again, I'm a novice so any help would be greatly appreciated. If this is the wrong place to be asking this question, please accept my apologies. Thanks in advance.

5/4/2005 10:54 PM
Tony	I would simply replace the volume control with one that has an off switch incorporated in the back of the pot that would disconnect the high voltage to the plate of the power output tubes.

5/4/2005 11:00 PM
Jamie Madden	That's a good idea. I didn't even think of that.

5/5/2005 5:30 PM
Dave	I'm not sure they make a volume switch/pot that would be rated for the current with the ohms value you might need. I don't know what your amp is rated at but if its fused at 3 amps then you need a switch that is rated at 5 amps to be safe. Same would apply to a rotary switch where you want to switch main power... be careful. An amp tech can add a standby switch for you if you want....

5/6/2005 10:56 AM

I think in the long run you might have trouble with any new rotary switch; the only ones with high enough AC/DC ratings are very expensive. You could get a cheaper one and parallel multiple sections to achieve the current/voltage ratings required, but if you aren't adamant about a rotary, here's a link for a single toggle switch that will do both on/off and standby.

http://www.westlabs.com/Frames.HTML

5/6/2005 11:08 AM
Jamie Madden	Thanks for all the help guys but I think I've decided to just install a SPST toggle switch for the standby since there is already a free hole in the chassis. The former owner drilled it for an external speaker out. I was gonna fill in order to put the amp back in stock condition but now I think I'll just put my standby switch in there.

Page 1 of 1