6.3 switching supply question

[Lindz]

Hello

My new build utilizes a switching supply for channel switching ldr's

Schematic calls for 6.3v ac and utilizes a DB101 rectifier etc for the supply. See layout + schem below

However my PT does not have an extra 6.3v tap and I understand using the filament supply can be noisy for switching, so I bought a small 6.3v (3.2v x2 plus center tap) ac transformer to power it.

Since this small transformer has a center tap I assumed it should be grounded and hooked it up that way

But when testing the switching supply the voltages are incorrect and it does not seem to function - going over my work I think I may have hooked it up incorrectly..

Since a DB101 is a bridge type rectifier (I believe), should I have instead floated the center tap on the 6.3v PT, or grounded it or the DB101 in some other manner than shown?

I essentially hooked up everything as shown but my separate 6.3v transformer has a center tap to ground whereas the schem shows 6.3v from the main PT w/no center tap, and that seems to be the only variation in terms of what I have done vs the schem.

thanks!

[JazzGuitarGimp]

Float the ct.

[Lindz]

tried floating the CT and still no go..

perhaps I cooked the rectifier by firing up the amp with the ct of the 6.3v PT grounded?

Any idea if I would have zapped the LDR's or perhaps even the PT as well by doing this? There was certainly no fireworks or smoke although the 6.3v PT got quite hot when the center tap was grounded. Had the amp on and running for a few minutes while taking voltage readings throughout the amp to test everything.

I'm just concerned that I will have a perpetual problem of zapping components if I do not replace all that possibly blew out, but obviously only want to replace bad components vs everything in the switching supply

Any suggestions?

[Structo]

I think I would try the least expensive option.

I had a quick lesson with a bridge rectifier myself, I grounded the CT and it didn't work.

First you can test the bridge rectifier with an ohmmeter but perhaps the simplest way would be to try another one, if you have one.

[John_P_WI]

Yeah all of us have toasted a bridge rectifier before, guessing that is your problem here.

Remove the bridge and use 4) 1N400X whatever you have laying around diodes in a "X" fashion to make your own bridge.

I'd remove the jumpers down line until you know you have it wired correctly.

As others have said, leave the CT disconnected.