From what I have, pins 2:3-6 are the two inputs and the two outputs of the preamp section on the smaller vertical board.
I think you'd have to pull the short board. The other could likely remain. The diagram isn't complete. A LONG time ago, Zapco provided this diagram. Contact them to see if they will provide the vertical boards. If they will not, pull the short board and see if it works as desired.
Ok, i will try..
I have asked to Zapco for schematics, but no reply yet.
With this configuration (without dsp), i don't have gain regulation, is complicated to add this feature?
I have asked to Zapco for schematics, but no reply yet.
With this configuration (without dsp), i don't have gain regulation, is complicated to add this feature?
I have tryed. With this configuration (pin19 to 21 and pin20 to 22), have a clipping with 6.5Vpp sine wave input. Other thing, i have one channel 180° phase reversed. I think, the gain is on the middle, i need some adjust + and -
Having one channel inverted makes it bridgeable.
Are you saying that it takes 6.5v to make it reach clipping?
If you insert a 1k resistor (1k-10k should tell me what I need to know) does the gain of the channel change?
If so, how much vs with no resistor?
Are you saying that it takes 6.5v to make it reach clipping?
If you insert a 1k resistor (1k-10k should tell me what I need to know) does the gain of the channel change?
If so, how much vs with no resistor?
In place of the direct jumper between the two points (for one channel) on the preamp board connector.
Drive a signal into the amp, measure the output of the channel. Insert the resistor and do the same with the same input signal.
Drive a signal into the amp, measure the output of the channel. Insert the resistor and do the same with the same input signal.
With 1kohm resistor on this point, i have input clipping with 20vpp sine wave, no output clipping, or with the same signal, i have 10vpp (output connector) without resistor, and 2.5vpp (output connector) with resistor
Go back to a jumper.
Increase the value of R150. 30k, if you have it.
How much input does it take to get to clipping?
Increase the value of R150. 30k, if you have it.
How much input does it take to get to clipping?
Replace R105 and R106 with a 10k resistor.
What does that give you for the output clipping vs input?
What are you using for a signal source now?
What will be the signal source in the vehicle?
What does that give you for the output clipping vs input?
What are you using for a signal source now?
What will be the signal source in the vehicle?