Heat sink on filter vregs

Ok, so i overestimated my electronic knowhow and bridged the two vregs 7805 and 7905 with a aluminum plate(bolt&screw) since i foolishly thought i’ll keep them cool both thermally and aesthetically without measuring any resistance before which now i learn is +/- 45k.
Since on 7805 gnd is on 2nd pin also connected to the thermal pad and on 7905 gnd is on 1st yet not connected to the pad results that i shorted gnd and the input of the 7905(2nd pin=pad) respectively 5th pin on the LT1054 . No sound came after this, removed the heat sink sound came back but i feel like there is a quite noise, hard to remember if there was any before. Did i just altered smth around, or i’m just paranoid?

The lt1054 is pretty fragile to shorts, it’s damaged easily. When its not working you would typically get no sound. It is possible that a partially damaged lt1054 creates a wobbly/unstable negative power rail, but without a sound example its hard to judge if everything is fine or not.

Thank you for the quick reply


hmm, smartphone browser is jumpy… I’ll swap it with an unused one and compare them by ear. Should I see something on my cheap dso138 scope?

VOUT (Pin 5): In addition to being the output pin, this pin is also tied to the substrate of the device. Special care must be taken in LT1054 circuits to avoid pulling this pin positive with respect to any of the other pins. Pulling Pin 5 positive with respect to GND will forward bias the substrate diode which will prevent the device from starting. This condition can occur when the output load driven by the LT1054 is referred to its positive supply (or to some other positive voltage).