Nothing to do indeed but the same input stage, the same power supply, the same buffer (minus the ccs) and the same servo I see your point though. I'm gonna try.
post #1081 of 1686
10/24/09 at 3:30pm
I hate to ask, but you got the right regs in the right spots?
And tubes are out, jumpers are not inserted?
Sorry about the Digikey problem. Since I used the Mouser parts I didn't catch it.
Do you think this will fix the problem?
To drive the analogue VU meters, I used the driver circuit as depicted below. The working of this driver circuit is very simple: the amplifier around T1 and T2 amplifies the line level signal to the desired level, the signal is then passing through the rectifier diodes D1 and D2. C4 smooth out the signal a bit before the signal is feeding to the VU meter.
Before use, an adjustment needs to be made.
Connect the circuit + VU meter to a function generator which output a 1KHz signal, ~300mV.
Dial P1 to its minimum (R=0), then dial P2 until the VU meter is reaching its maximum.
Next, turn P1 up until the VU meter is at ~ 50% of its total range (12 o’clock).
Depending on the level of the input signal (SACD player, DAC…), you might have to re-adjust P1 to get a proper reading of the VU meter.
For stereo application, 2 driver circuits are needed.