Custom Power Board

[matam]

I'm gonna rebuild the power board of my RM100 and while i'm at it i think i'll do a couple of mod on it.

I'm researching a way to implement a switch that let me select between 4 power tube or one of the two pair; assuming we use mixed powertube it will have the option to chose wich pair to use (Ex: 2 6L6 or 2 EL34) like on the RT2/50 poweramplifier.

I'm also studing various powersection of famous amp to see what else can be done.
My idea was to implement some controls switch between a couple of differnt sounding powersection.

If you have some idea of what can be made for the powersection of the RM100 i'm listening to any kind of suggestion.

I'd like to take a look at the RT2/50 schematics also but i seem i cannot find them.

 

[BigBrewtus]

Thought about adding a rectifier tube option? Or a switch between tube rectification and solid state?

 

[matam]

Thought about adding a rectifier tube option? Or a switch between tube rectification and solid state?

I didn't and i think it's a nice idea, thanks.

Another thing i've had in mind is an instrument/line level switch for the loops;
i should check also the input of the amp, we've half valve that isn't used there.

 

[Tbag]

Well ahead of you

 

[kc2eeb]

Easiest way to disconnect power tubes is to un-ground the cathode. You can put a spst switch in series with the 1 ohm resistor used to measure the bias current.

 

[JeffHenneman]

How about putting a deep and modern switch like a Mesa 2:90 has.

 

[nomad100]

why do you have to rebuild the power board?

 

[matam]

Sorry no new info, i didn't have much time to work on the project.

why do you have to rebuild the power board?

Because my RM100 comes from an old batch and have the old powerboard revision, and it arched in the same place as many other forum users here the first time i pushed the master volume a little over 13:00.
I contacted randall customer service more than a month ago asking them where i could buy the new revisited powerboard.
I'm still waiting for them to tell me how much it does cost and where to get it; i'm sick of waiting and i think it'll be less expensive for me to do it myself.

In the meantime i've fixed it by going around the problem; i've made a couple of gigs with it and both went well, but i would like something better than a "going around the problem" type of fix.

 

[kc2eeb]

Just to be clear, are you rebuilding the Power Amp Board that has the
Output Tube sockets on it or the Power Supply Board that has all the filter caps and rectifiers on it?

 

[nomad100]

good questions i assumed the power supply board, but for a deep mod stuff that would probably the the power amp board. Probably mostly in the NFB loop.