F1 Amplifier circuit clarification..

[suds]

Hi,

1. I need some clarification, for LED wiring

LED is in parallel with P2, and P2 is in series with (R20) 10K resistor connected to output.

when P2 is adjusted, will it not make difference in output ??
to adjust LED, I suppose P2 Pot need to be in series with LED and ground. !!!

[ECM]

If you raise the wiper arm of P2, you effectively form a straight wire in parallel with the LED. Path of least resistance will be thru "0 ohm" P2 and LED will not illuminate.

At least that's the way I see it.

[suds]

Yes, when P2 is at 0 resistance, and since P2 is connected to Out, so it will make 10k connected to ground, will this not change the Output ??
I suppose when we vary P2, the resistance between Out and ground will vary, (minimum being 10k.. ) this should make a difference!

if you observe the PCB track print, LED is in series with P2...

how come there is difference in Schematic and PCB ??

[suds]

One more observation,

In PCB (As per F1 Manual )

Resistor R1, R13 is connected to one end of Cap C1,
Other end has, Z1, R3, R5, R7 And gate of Q1

similarly,

Resistor R2, R14 is connected to one end of Cap C2,
Other end has, Z2, R4, R6, R8 And gate of Q1

But in PCB, Cap C1, seem to be connected to R3,R5,R7,ZX1

(C2 connected to R4,R6,R8,Z1)

where R3,R5,R7,ZX1 (and also R4,R6,R8,Z1 )are interconnected with single track (wire)

compare f1 Manual, schematic and PCB Layout..

-Suds

[ECM]

The schematic shows the LED connected to the output which in the manual states is at 13.8 volts. When music is played, that will change and I would assume the brightness of the LED would change as well. I'm not sure why Mr. Pass just didn't wire it to the power supply. I have not built this circuit so I cannot be 100% sure on this.