[bizzlebot]

The LED light and VU light are not illuminating.

i have all the right values for -12V, V-, V+, and +12V. Additionally I see 600OHM (roughly) across the VU outside leads. I verified the LED works with my DMM.

I checked for any shorts along CN2B based on the other thread I was reading. Can you help me with what else I need to test?

Thanks!

[bizzlebot]

Additional Details:

- Check the meter (unplugged): 600 ohms between the large terminals, infinite resistance between any 2 other terminals. 
- - - 582 ohms
- Check the relay coil (in circuit), 2800 ohms across D19 (check D19 direction). 
- - - 2900 ohms
- Check R104 value (in circuit).
- - - 220 ohms
- check pin 2 shorts to LED Long.
- - - It is shorted between that 2nd pin and the LED Long (d3)
- Check CN2A shorts
- - - Not shorted

I verified all the diodes face the right way, solder joints are solid, etc. Thanks again!

[JPK]

With the DMM in diode position, check that the LED D3 illuminates in one direction.
Check there is no short circuit across small/large terminals on the meter.

[bizzlebot]

LED lights up and there is no short. 

Please see this link with pictures (3) of the circuit as well as the LED working/no Short with the DMM.

thanks for your help!

https://imgur.com/a/BRVc3ea 

[JPK]

It was not necessary to remove the LED for the test.
Check that you still have the connection between the top and bottom LED pads.
Did you have to remove other components during the build? In such case, it is necessary to check that the via that connects the top and bottom pads is not destroyed. You can repair it by soldering the component leads on both sides.

[bizzlebot]

I didn't remove any other components, that was only to test the LED. 

The vias are connected from top to bottom (tested with DMM). should I solder the LED back in?

[bizzlebot]

I performed all the tests for PCB-A from "In case your CP4500 doesn't work as expected". everything works there, and here are my values for reference. The meter doesn't move during any of the tests, but I know the meter works because I tested it with a small voltage and the needle moves. I'm wondering if there is something I can test on PCB-FRONT?

Mix = 100%
Ratio = 10
Attack = 0.1
Release =1.2
IN button pressed
HF lift, 100Hz, 50Hz buttons released
Negative meter probe on 0V


V+ =+15 to +16VDC, -> 16.0
V-  =-15 to -16VDC), -> -16.22
+12V = +11.1 to +12.9VDC, -> 11.95
-12V  = -11.1 to -12.9VDC -> -11.8







Step 1 conditions plus:
Input signal = 0V
Threshold on +15
Makeup on 0


TP1, TP2, TP3, TP4, TP11, TP12 = 0VDC -> all 0






Step 1 conditions plus:
Input signal = 0V
Threshold on +15
Rotate Makeup from 0 to +20


TP12 goes from 0 to -2.3VDC -> 0 to -2.35V







Input signal = 0V
Makeup on 0
Rotate Threshold from -15 to +15

TP13 goes from -1.8V to +2.8VDC -> 1.81 to 2.83




Input signal = 3VAC
(measured between output XLR pins 2&3
with compressor bypassed)
Makeup on 0
Threshold goes from +15 to -15




TP4 goes from 0.060VAC to 0.190VAC .06 -> .186
TP5 goes from +0.35VDC to a negative value -> .33V to -1.2
TP11 goes from 0VDC to -3.5VDC -> 0 to -3.53
TP12 goes from 0VDC to +3.5VDC -> 0 to 3.53






input signal = 3VAC
Threshold on +15
Makeup on 0


Signal level (VAC) on
TP1=1.5VAC, -> 1.48
TP2=1.5VAC, -> 1.58
TP3=1.5VAC, -> 1.48
TP4=0.06VAC, -> .06
DC voltage (VDC) on
pin 1 of U6 (white dot) = 0V -> 0






input signal = 3VAC
Threshold on -15
Makeup on +20




Signal level (VAC) on
TP1=1.5VAC, -> 1.488
TP2=0.4VAC, -> .438
TP3=1.5VAC, -> 1.488
TP4=0.2VAC -> .186
DC voltage (VDC) on
TP11=-3.5VDC, -> -.352
TP12=+1.2VDC, -> 1.185
TP13=+1.7VDC -> 1.71

[bizzlebot]

LED Fixed. The issue was that the Meter LED wires were backwards (I misread/misunderstood the picture). All good now thank you!

[JPK]

Congratulations!