I remember having to be careful when dialing in the bulb on other univibe builds...can you suggest a starting position on the trimpot (is it trimpot 3)?
Blend - Adjusts the blend of clean / vibe signal
Gain - Adjusts the intensity of the lamp
Offset - Adjusts the DC bias (mid point) of the sweep
I would start with the Gain and Offset near the middle and adjust from there. Just watch the brightness of the lamp, I've never really considered the fact that you could blow the bulb, but I suppose it's possible (12V bulb running on a potential 18V source).
Blend - Adjusts the blend of clean / vibe signal
Gain - Adjusts the intensity of the lamp
Offset - Adjusts the DC bias (mid point) of the sweep
I would start with the Gain and Offset near the middle and adjust from there. Just watch the brightness of the lamp, I've never really considered the fact that you could blow the bulb, but I suppose it's possible (12V bulb running on a potential 18V source).
Blend - Adjusts the blend of clean / vibe signal
Gain - Adjusts the intensity of the lamp
Offset - Adjusts the DC bias (mid point) of the sweep
I would start with the Gain and Offset near the middle and adjust from there. Just watch the brightness of the lamp, I've never really considered the fact that you could blow the bulb, but I suppose it's possible (12V bulb running on a potential 18V source).
You should be ok. The bulb is rated for 12V @ 40mA. The 18V isn't really 18V, probably more like 17V. With TR2 fully CCW and TR3 fully CW, the most DC voltage the bulb could see is around 12.5V. The thing that kills incandescent bulbs is the large current surge when you first turn them on. Q3 acts as a current limiter and keeps the peak current down to a very safe level.