Rotary Switch for multiple switching/High voltge also

[RockinRocket]

Looking for a robust rotary switch that would allow for multiple switching at once with 5 positions. Id like to add a year switch on my JMP build. I am looking into being able to switch cathode resistor, bypass cap, negative feedback, droping resistors and high to low voltage all on one turn with a total of 5 settings. Possible switching filtering. Is this just asking for trouble?

Something like this maybe but needs to be able to pass 440vdc safely.

http://www.mouser.com/ProductDetail/Ele ... 8d6J3pU%3d

I was also thinking of putting simple 2/3 way switches under the knobs and switch them in and out individually but that would be annoying and one main rotary switch would be ideal.

[Structo]

What is a year switch?

[Stevem]

Bringing all those sources into one area to hook up to a switch is a asking for a amp that will be a oscillating nightmare!

[Phil_S]

What is a year switch?

The one you cut off the tree last year as an implement of corporal punishment?

[RockinRocket]

What is a year switch?

Ive pretty much pinpointed the differences in the JMP 50s from 68-to the low volt mk2s. 68,70,72,Mk2, Mk2 low volts, Pretty much sums up the major differences in circuit variances.

[RockinRocket]

Bringing all those sources into one area to hook up to a switch is a asking for a amp that will be a oscillating nightmare!

That's what I was afraid of. Something robust and big like the electoswitch if it was able to handle the volts I thought would be a good option.

http://www.mouser.com/ProductDetail/Ele ... 8d6J3pU%3d

[JTU]

Could be made to work with relays, although a relay for switching HT might be expensive/big/hard to find.

[Firestorm]

There are octal relays that typically run the coil off 115VAC and have contacts rated for several amps. They must have been used in old TVs because you find them in TV/radio repairmen's stashes. Now for industrial equipment I assume. They take up a fair amount of real estate.

Personally, I would switch the HT separately with a robust toggle, and switch signal level components with small local relays to keep signals from interacting. You certainly don't want later stages wrapping back to earlier ones. If I'm counting gain stages correctly, your NFB would be in phase with the first stage cathode and grid.

[RockinRocket]

I was thinking relays as well. I was hoping that one turn or flip of a switch could switch volts and activate relays. Is that even a possibility?

[Stevem]

Have you incorporated these changes one at at time to even see that they give you what you are expecting?
Just ask how many folks here have spent many many hours on a mod or in a amp build only to find that things did not work out for there sonic needs like they where hoping for !

[RockinRocket]

I have played with 1970s and 1972s variations of my amp and played a low volt mk2. I may find one setting and leave it there but Im more interested in the idea chase than the practical use of the amp!

[R.G.]

Don't even try to use a single hard switch to do all that.

Use high voltage MOSFETs for cold-switching: put the MOSFETs out at the circuit being switched to do the actual make/break depending on how their gate is being driven, then isolate the gate drive with some LED-PVI isolators and do all the switching at a low voltage level driving the LEDs. No voltage stress or current stress on the switch, which can now be cheap without being a safety hazard.

Takes some circuit design skills to select MOSFETs and PVIs and make those work reliably, though. Probably cheaper than an equally capable hard switch.

[rp]

For power flavors Marstran makes a 290/330V w/ 5V, build the PS with a rectifier socket, a secondary switch, and a Mojo plugin ss thing and you have options of - tube, ss, ss high. You can also get Heyboer to wind you anything you want if he's out. For V1/V2 maybe this switch below can help? With push pull pots, you can also use guitar dptp switched pots, and if you can wrap your head around the permutations, you might be able to get all the marshalls from 1964-1988 in there

http://www.tube-town.net/ttstore/Switch ... :6792.html

http://www.tube-town.net/ttstore/Switch ... :6785.html

Myself, I would just build all the different Marshalls

[rp]

this might help too:

sluckey dual preamp 1987/2204 switchable amp
http://el34world.com/Forum/index.php?topic=9602.0

[RockinRocket]

rp I would be using Marstran dual tap power transformer. Sounds like 6 mini toggles under the controls would be the safest way to go and a dual volt power switch. Its interesting how just a few value changes can change the tone but still retain that vintage 4hole tone. I do find I like buckers better with a 68/70' spec and p-90s with the 72' spec.