Hoffman Amplifiers Tube Amplifier Forum

Other Stuff => Solid State => Topic started by: SILVERGUN on April 29, 2014, 11:30:30 am

Title: Need help wiring a relay
Post by: SILVERGUN on April 29, 2014, 11:30:30 am

I currently have a front panel SPDT toggle switch to switch between OD and Clean channels.
How do I wire a relay so that I can use a footswitch to over-ride the setting of the panel switch?

I'm just having a cloudy brain day, and limited time, and just can't find the info quickly, in Doug's library or on a schematic..
Even if you just know of an old thread or just a schematic that uses this hookup,,,,I just need to see it, and I'll be good.
Forum search comes up with waaay too many options.

I labeled the switch contacts in red as 1 , 2 , and 3, in case it's easier for you to just tell me to connect numbers..

Thanks!....I must be making this harder than it has to be...  :dontknow:

Title: Re: Need help wiring a relay
Post by: sluckey on April 29, 2014, 12:19:49 pm

This is what I'd do...

Wire the relay contacts to actually switch the OD and clean signals. Now use this circuit to energize the relay coil. Works just like a 3-way light switch in your house. You will be able to energize or de-energize the relay coil from either footswitch or front panel switch. See pic...

Title: Re: Need help wiring a relay
Post by: SILVERGUN on April 29, 2014, 12:44:59 pm

Nice...
Very well illustrated and easy to see.
THANK YOU!

I'll use a shorting jack for the footswitch, and wire it so that when it isn't plugged in there will still be a path to the power supply.

Title: Re: Need help wiring a relay
Post by: tubenit on April 30, 2014, 05:34:37 am

Sluckey gave you an answer.  IF you need more information, please remember in ARCHIVES there is a lengthy thread with lots of illustrations and photos.

http://el34world.com/Forum/index.php?topic=14348.0 (http://el34world.com/Forum/index.php?topic=14348.0)

With respect, Tubenit

Title: Re: Need help wiring a relay
Post by: SILVERGUN on April 30, 2014, 07:27:08 am

Thanks T,
That's a great thread!

For any of you kids out there at home who are following along, the most important thing that I can point out is to:
MAKE SURE YOU ISOLATE THE FOOTSWITCH JACK IF YOU'RE USING A STANDARD SWITCRAFT 12A SO YOU KEEP THE RELAY POWER SUPPLY FLOATING FROM THE CHASSIS.

I tried using the isolation washers that Doug sells, BUT my chassis material is not thick enough to fill the gap between the 2 washers, so I'll be waiting for a Cliff type jack to come in.....unless there is another idea..?

Title: Re: Need help wiring a relay
Post by: Willabe on April 30, 2014, 08:55:17 am

Quote from: SILVERGUN on April 30, 2014, 07:27:08 am

unless there is another idea..?

Yes, you can use 1 shoulder washer and 1 flat washer. (You might be able to cut or file off the shoulder?)

That's what I use but I use the nylon type.

             Brad    :icon_biggrin:

Title: Re: Need help wiring a relay
Post by: SILVERGUN on April 30, 2014, 04:08:53 pm

Quote from: Willabe on April 30, 2014, 08:55:17 am

Yes, you can use 1 shoulder washer and 1 flat washer. (You might be able to cut or file off the shoulder?)

I used both shoulder style and filed one flat,,very easily...THANKS!

Title: Re: Need help wiring a relay
Post by: Willabe on April 30, 2014, 07:37:46 pm

Good deal! Glade it worked.


       Brad     :icon_biggrin:

Title: Re: Need help wiring a relay
Post by: SILVERGUN on May 14, 2014, 11:57:34 am

I drew up a little wiring diagram to complete this thread......(and for sluckey to check my work)  :icon_biggrin:

This amp will be used on the OD channel much more than the Clean channel, so I made the clean channel the one that will apply +5vdc to the relay,,, so that the relay coil will be de-energized with the amp switched to the OD channel.