Standby Switch - How does it work?

[Musical123]

I just got an SOB and am not sure if the standby switch works properly.

Can someone please explain how this works and the right way to use it? This is my 1st tube amp.


Thanks

 

[Boogiebabies]

Sounds like a safe practice George.

The standby is essetially an on/off switch for the high voltage needed for the preamp tubes and power tube plates and screens etc. When you turn the amp on with the main power switch it turns on only the low voltage taps, like the bias and the the 6.3V taps for the tube heaters, thus, when you turn the amp on, the tubes light up. It also basically opens the wall voltage to your power transformers primary and fan. The standby is shorted with the switch to prevent shocking a cold tube with 460+ volts. When on, it connects the filtered and rectified main filter supply and the preamp filter supply and the choke. Once the preamp and power amp tubes get the high voltage, they can work properly and you get amplification via the use of Thermionic Valves. :wink:

 

[igfraso]

On the starting procedure, everyone agrees.

On the shutdown, I heard something different. I was told to turn off the power while ligthly strumming the strings of the guitar.
This unloads the capacitors and, when you don't here any more sound coming out from the speaker, you switch the Standby off.

Is this correct or advisable Boogiebabies?

I know that, anyway, if I am going to remove the chassis I need to follow this procedure to unload the capacitors.

Thanks in advance.
Daniel

 

[Boogiebabies]

On the starting procedure, everyone agrees.

On the shutdown, I heard something different. I was told to turn off the power while ligthly strumming the strings of the guitar.
This unloads the capacitors and, when you don't here any more sound coming out from the speaker, you switch the Standby off.

Is this correct or advisable Boogiebabies?

I know that, anyway, if I am going to remove the chassis I need to follow this procedure to unload the capacitors.

Thanks in advance.
Daniel

Before I turn off the standby, I switch to clean, put the master on 3, then turn off the standby while strumming. You can hear the last few blurbs come out and then I just shut it off. Most of the time if you are playing at low master volumes, like 1, it will fart or sqeal on shut off because the caps are discharging through the speaker. I hate that, so I use the strumming method and she never groans or has any flatulence. As far as fully discharging the caps, I always check them with a meter regarless. Sometimes they can still hold 63V or more. I use a 10 Ohm/5W resistor to ground and they will usually drain to below 9V pretty fast. I don't like the screwdriver method. It's a big pop and it usually has a small hot sliver of metal coming off the chassis.

 

[Buddy]

THERMIONIC VALVES

 

[Boogiebabies]

THERMIONIC VALVES

I was baiting with the retort, " What's a Thermionic Valve". 8)

 

[Buddy]

THERMIONIC VALVES

I was baiting with the retort, " What's a Thermionic Valve". 8)

Adulthood ..... Who would of thought .... exit ..stage right ...(edit)
....any way , where was I ? Ah! ; "No one ever complained about their tone being obscured by electron clouds ." you can use that .

 

[Buddy]

Huh , wait a second . Who was it that said " We can't use that track , the guitar is distorted ! "
**** .

Now THAT'S a great quote .
I think a Boog was involved , but it may be wishful thinking .

 

[igfraso]

Before I turn off the standby, I switch to clean, put the master on 3, then turn off the standby while strumming. You can hear the last few blurbs come out and then I just shut it off. Most of the time if you are playing at low master volumes, like 1, it will fart or sqeal on shut off because the caps are discharging through the speaker. I hate that, so I use the strumming method and she never groans or has any flatulence. As far as fully discharging the caps, I always check them with a meter regarless. Sometimes they can still hold 63V or more. I use a 10 Ohm/5W resistor to ground and they will usually drain to below 9V pretty fast. I don't like the screwdriver method. It's a big pop and it usually has a small hot sliver of metal coming off the chassis.

Thank you, man!!
Very graphic and very accurate!!! Hahahaha!!
Your knowledge is amazing. Chapeau!
Daniel