Pre amp isn't working - but has good voltages
Posted: Sat Jun 11, 2016 12:16 pmI just finished building my N72 and checked all of the voltages.
From pin 1 to pin 2 had infinite resistance and from pin 2 to pin 3 I have just under 1k ohm.
I easily set the voltage from pin 2 to Q6 to 22.2
I then powered up the N72 and had no apparent problems but had no signal output.
I went ahead and checked all the readings following the instructions and got these values:
Collector Base Emitter
Q1 4.04 2.54 1.96
Q2 13.1 4.04 3.41
Q3 21.9 13.10 12.47
Q4 6.46 .87 .30
Q5 22.2 6.46 5.89
Q6 22.2 5.96 5.35
I noticed some of my levels were off. I'm currently double checking all of my resistors to the schematic. I'm puzzled why I would be so close but still have no signal.
If you guys have any suggestions I would greatly appreciate it.
Thanks
From pin 1 to pin 2 had infinite resistance and from pin 2 to pin 3 I have just under 1k ohm.
I easily set the voltage from pin 2 to Q6 to 22.2
I then powered up the N72 and had no apparent problems but had no signal output.
I went ahead and checked all the readings following the instructions and got these values:
Collector Base Emitter
Q1 4.04 2.54 1.96
Q2 13.1 4.04 3.41
Q3 21.9 13.10 12.47
Q4 6.46 .87 .30
Q5 22.2 6.46 5.89
Q6 22.2 5.96 5.35
I noticed some of my levels were off. I'm currently double checking all of my resistors to the schematic. I'm puzzled why I would be so close but still have no signal.
If you guys have any suggestions I would greatly appreciate it.
Thanks