Best standby switch wiring in 2204

[Steveo]

Hello, in my amp i have

bridge rectifier - filter cap - standby switch - ht fuse - choke and ot center tap.

But i also see in other layouts

Bridge rectifier - standby switch - filter cap - ht fuse - choke and ot center tap.

The filter cap is after the switch not before like mine.

What do you prefer?

My amp when playing at high volume and high gain will squeal for two seconds when i put it into standby. I was wondering if it was because of my standby switch configuration. It wont do this at moderate volumes.

Thanks

[xtian]

The best plan is not to use a standby switch at all.

[frankdrebin]

you can wire the standby to the screen grid line only,that is much less stressful on the contacts,Peavey used to do that

[sluckey]

I would use a DPST switch between the PT and diodes just like Marshall did.

https://el34world.com/charts/Schematics ... w_2204.pdf

[R.G.]

It's a question of objectives - what do you want a standby for? Here are some possible reasons.
1) just because this amp (or other amps historically) have one
2) to mute the amp but be able to have it fire right up instead of waiting for the tubes to warm up for short quiet periods
3) to save wear and tear on the tubes from multiple heat/cool cycles
4) some other reason of your own? Stopping the squealing is a good one.

For reasons one through three, you get just as good a result from rewiring the standby switch so it mutes the input to the power amp. It's safe and effective.

[Guy77]

I have been using this setup a lot and have not experienced any issues.

bridge rectifier - filter cap - standby switch - choke and ot center tap.

2R also does similar setup.

Cheers

Guy

[Steveo]

I have been using this setup a lot and have not experienced any issues.

bridge rectifier - filter cap - standby switch - choke and ot center tap.

2R also does similar setup.

Cheers

Guy

Do you hit the ht fuse at any point from your standby switch?

[pdf64]

Just to note that the 2204 has a 2 phase rectification.

[Guy77]

I have been using this setup a lot and have not experienced any issues.

bridge rectifier - filter cap - standby switch - choke and ot center tap.

2R also does similar setup.

Cheers

Guy

Do you hit the ht fuse at any point from your standby switch?

No I do not. I just noticed you are referring to a 2204 amp which I have not built many of. Maybe someone that has more experience with that will chime in.

[sluckey]

I don't think I've ever seen a 2204 with a bridge rectifier.

[Steveo]

No sorry, i messed that up. Its just the normal 2204 2 phase in this amp.

I think will try the normal marshall style of standby as sluckey suggested, just got to order a switch.

Thanks all!

[Steveo]

I installed the new switch but im getting a short loud electrical type hum when i take the amp off of standby. Only lasts about a second or so. Maybe its the in rush to the first filter cap? Its louder at 120vac than at 90vac. The filter caps are only a year old.

The standby switch is now wired like a normal marshall 2204. The DPST is between the PT and the diodes.

[pdf64]

Is the bias circuit energised whilst the amp is in standby mode?

[sluckey]

It is if he wired it IAW the original schematic.

[pdf64]

It is if he wired it IAW the original schematic.

I dunno, Marshall were wiring their 50 watters like that for maybe a decade, including the first 2 iterations of the 2204 (JMP era) https://el34world.com/charts/Schematics ... l_2204.pdf