Valve amp enthusiasts?

[volospian]

Just checked, I have 4 marshal style silver and black knobs that may look nice on your amp, if you want them! Drop me a pm if you want them.

[Jonny69]

Originally Posted by volospian

Just checked, I have 4 marshal style silver and black knobs that may look nice on your amp, if you want them! Drop me a pm if you want them.

Ooo, might well be interested in these ones. What diameter are they?

I've done a test layout with some miniaturisation to squeeze the components up. Firstly I've used a smaller timing capacitor value so the capacitor itself is physically a lot smaller, secondly I've used a ceramic stabilisation cap instead of the polystyrene one (or polyester - can't remember), which is a lot smaller. Finally, I've put the link between pins 2 and 6 (green wires below) underneath the chip holder instead of either side, which saves me 5mm width and one horizontal track.

Before (the diagonal resistor on the left is in fact a mistake but the circuit still works):



After:



Note the second resistor is now in the correct place. There's no choke or output load yet and the two transistors I'm using for current are small three-pin devices which take up nowhere near as much space as the big silver NE 3055 on the right. I should be able to fit this part of the circuit up above, leaving plenty of space for the transformer, diodes and smoothing cap.

[volospian]

Originally Posted by Jonny69

Ooo, might well be interested in these ones. What diameter are they?

Can't remember off hand, but they're the usual size found on Marshall guitar amps.

Probably the same as these...

[volospian]

Jonny,

Sorry, I forgot all about this. They're ~20mm (give or take 1mm, I could only fiind the wifes dressmaking tape measure in the house and it's raining, so I can't be ar5ed to go to the garage). Ihave 4. If you want them, pm me your address and I'll send them.

[Jonny69]

No worries. I found another identical volume knob on eBay. Amazing that they still make them the same