Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: dinkyguitar on April 08, 2020, 08:43:39 pm

Title: Initial tube amp power on after build & standby switch questions
Post by: dinkyguitar on April 08, 2020, 08:43:39 pm

Hi All,

I'll be building an amp in the upcoming weeks and I've been reading a lot about tube amps.

I've read how to power on amps for the first time after a build and they mention powering it on with the standby switch on.

And by this they mean when I use my regular tube amp and the standby switch is on, the amp is on, but there's no guitar signal. To me, the standby switch has always been mislabeled, but that's a different discussion.

Once standby is on, checked heater voltage, transformer voltage etc. without tubes.

So my question is, with standby on.....what components have power to them?

Is power in the caps? resistors? circuit board?

What's the purpose of having the standby switch on or off during this initial testing without power tubes?

dinky

Title: Re: Initial tube amp power on after build & standby switch questions
Post by: sluckey on April 08, 2020, 09:53:01 pm

There are several different ways to implement a standby switch in an amp. You need to specify an amp and provide a schematic to give any specific answers.

But usually a standby switch interrupts the B+ voltage in some manner.

Title: Re: Initial tube amp power on after build & standby switch questions
Post by: Latole on April 09, 2020, 06:07:10 am

Quote from: dinkyguitar on April 08, 2020, 08:43:39 pm

Hi All,

 So my question is, with standby on.....what components have power to them?
- Short answer ; All Tubes, output transformer high voltage ( B+ )

Is power in the caps? resistors? circuit board?
- Yes

What's the purpose of having the standby switch on or off during this initial testing without power tubes?
IMO no purpose
 

dinky