Studio Projects TB-1

[gary o]

I know this is old topic looking at schematic are the capacitor values correct ? .... the 022 uf caps connected to the capsule......thanks

 

[gary o]

I know its old topic BUT can anyone confirm Power supply B+ is 200V as indicated in the first post, I built this circuit assuming B= would be 120V it does work  at B=120V I get 73V on the plate & 1.428V on cathode, If I raise B+ to 200V will the plate voltage rise is 73V or higher too high already .....

thanks

 

[vieuxchien]

I know it's a real old topic...

But I'm looking for the schematics of the TB1 and the images have been deleted from the imageshack server :-(


any possibilities to have them ?

So, this is my first real attempt to contribute something back to the group.

i've got some nice mics whipped together, so i figured i might try to mod my studio projects tb1 and share it with everyone. i don't use it that much anymore, so what the hell...



the mic apparently has a 6072 tube, 797 capsule. sounds pretty good, but the highs are sometimes a bit too apparent. i figured i'll change the tube and a couple of components and go from there.

here's some pics.

to me, the construction doesn't seem that bad. the psu outputs 200v/2.5mA and 6v/100mA, didn't measure it yet though.

 

[pucho812]

I know its old topic BUT can anyone confirm Power supply B+ is 200V as indicated in the first post, I built this circuit assuming B= would be 120V it does work  at B=120V I get 73V on the plate & 1.428V on cathode, If I raise B+ to 200V will the plate voltage rise is 73V or higher too high already .....

thanks

Yes the supply puts out around 180-200VDC B+ or so would be labeled on the silk screen next to the multipin xlr