"freehand PS" = 4558 resignation / SCReverb

[petemoore]

Wired up 1rst 1/2 of Stage Center Reverb [Buffer/driver section].
Checked for no shorts between _14v/Gnd=0.0v/14V+ and...
Hooked it up to my power supply, transformer is supplying [whatever it was...] 11.9/0/11.9 Vac, into a diode diamond [FWR] then a big cap across V+/V_.
Opamp V+ gets +14VDC, Circuit grounds get 0.0vdc, [from transformer center tap] and and -9vdC to the V_ [pin4].
http://www.generalguitargadgets.com/..._reverb_sc.gif
Opamp lets out the blue smoke...back to...I wish I had this on a drawing board...should I be taking the circuit grounds and connecting them to the center tap..or..[by circuit grounds I mean the points marked with tapering length horizontal likes.

[Enzo]

When you put the bridge across that 12VAC-0-12VAC and ground the CT, you should get about 16VDC on each polarity with resspect to ground. You should filter each supply to ground, not one large cap from pos to neg. -9v is immediately suspicious. Should be more liek 15, so either it is not filtered or it is loaded down.

When you make a power supply, always test it by itself before applying it to a circuit.

Got C9 wired backwards?

Seems to me the board grounds need to connect to chasis ground ultimately, unless someone can point out somethjing I overlooked.

[petemoore]

There are two 39uf [I used 100uf] capacitors on the board strung between V_ and V+, where they meet is ground.
So I have a 68uf across V-/V+, a 100uf from V- to Gnd., another 100uf from gnd to V+. All caps have - towards 'down'...
And I'm measuring DC of '14/0/14' = 'V_/Gnd/V+'...seems like it should work.
Edit/revised circuit:
I dummied the power leads, as 50/50 chances would have it, the electrolytics told me so by overheating, however they were easily cut out, and 'adjacently' replaced...There are two 39uf [I used 100uf] capacitors on the board strung between V_ and V+, where they meet is ground.
Test #2..

[Mark Hammer]

Hi Pete,

I think the problem is that the 4558 is not spec'd to deliver lots of current to low-impedance loads. So, from where I stand, it's not the power supply as such, but rather the absence of any limits on what the 4558 is going to draw from the power supply. More succinctly, I think you smoked it because it was trying to behave like a power amp...and couldn't.

You need some sort of current limiting to the op-amp...or else a different op-amp or pan, or both.