Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: TubeGeek on October 17, 2015, 01:26:04 pm

Title: Looking for a diagram of an off/standby/on switch
Post by: TubeGeek on October 17, 2015, 01:26:04 pm

I recall seeing at some point a nice diagram of how to wire up a switch to act as a 3 in 1 switch for an amp.  Can anyone help me out?  I have spent an hour searching with no luck.


I have an 18 watt build that I want to remove the standby switch and use that hole for a VVR control pot.  I would like to use the one power switch hole for an off/standby/on switch.

Title: Re: Looking for a diagram of an off/standby/on switch
Post by: shooter on October 17, 2015, 01:54:50 pm

couldn't find it either, did find this;

http://www.netads.com/~meo/Guitar/Amps/Kalamazoo/Mods/standby.html (http://www.netads.com/~meo/Guitar/Amps/Kalamazoo/Mods/standby.html)

Title: Re: Looking for a diagram of an off/standby/on switch
Post by: HotBluePlates on October 17, 2015, 02:13:42 pm

You need a "Progressive Switch" which is a DPST, but has 3 positions not 2 (as you'd normally expect in a single-throw).

Hoffman sells the switch (http://el34world.com/charts/SwitchDPST.htm).

At one outer toggle position, both switch sections are open. In the middle setting, one (not both) switch sections closes. At the other outer toggle position, the remaining switch section closes.

Title: Re: Looking for a diagram of an off/standby/on switch
Post by: Willabe on October 17, 2015, 02:25:16 pm

Click on the link HBP posted, there's pictures there on how to wire it.  :icon_biggrin:

Title: Re: Looking for a diagram of an off/standby/on switch
Post by: TubeGeek on October 17, 2015, 03:35:40 pm

Yes! That's the one I remembered seeing before. Thanks!

Title: Re: Looking for a diagram of an off/standby/on switch
Post by: hesamadman on October 17, 2015, 06:03:10 pm

That's a very interesting concept. I myself would like to try it. However I could see that confusing some.

Title: Re: Looking for a diagram of an off/standby/on switch
Post by: sluckey on October 17, 2015, 06:49:30 pm

Here's another application for that switch that may interest some. Look at the Standby Plus mod...

     http://home.comcast.net/~seluckey/amps/VAC15/Vox_AC15_mods.pdf (http://home.comcast.net/~seluckey/amps/VAC15/Vox_AC15_mods.pdf)

Title: Re: Looking for a diagram of an off/standby/on switch
Post by: Fresh_Start on October 18, 2015, 12:52:24 am

Quote from: sluckey on October 17, 2015, 06:49:30 pm

Here's another application for that switch that may interest some. Look at the Standby Plus mod...

     http://home.comcast.net/~seluckey/amps/VAC15/Vox_AC15_mods.pdf (http://home.comcast.net/~seluckey/amps/VAC15/Vox_AC15_mods.pdf)

That's a really neat idea!  I love simple-clever.

You could apply the exact same idea to switching between tube and solid state rectification:

(http://www.triodeamplification.com/images/rect_ss-tube.gif)

Chip

Title: Re: Looking for a diagram of an off/standby/on switch
Post by: sluckey on October 18, 2015, 06:53:26 am

That's a good idea too!

Title: Re: Looking for a diagram of an off/standby/on switch
Post by: EL34 on October 18, 2015, 08:18:48 am

I have that info as a link right next to the switch on this page
http://hoffmanamps.com/MyStore/catalog/Switches.htm (http://hoffmanamps.com/MyStore/catalog/Switches.htm)

Title: Re: Looking for a diagram of an off/standby/on switch
Post by: MFowler on October 18, 2015, 09:26:15 am

Great photo of that progressive standby switch wish I would of had that when I was struggling to understand my instructions from another supplier:)

Title: Re: Looking for a diagram of an off/standby/on switch
Post by: EL34 on October 19, 2015, 06:23:30 pm

Thanks>
I try and make it as easy as possible for guys using that switch
http://el34world.com/charts/SwitchDPST.htm (http://el34world.com/charts/SwitchDPST.htm)