Troubleshooting help needed - voltages wrong

Troubleshooting help needed - voltages wrong

Postby csanii » Tue Feb 05, 2019 8:22 pm

Problem seems very similar to:
JP4 has not been shorted.

My voltages are almost identical with L3 connected.
Theirs: TP22: 0.99V, AV-: 0.59V, AV+: 1.29V, +3.3: 0.23V, +5: 1.78V, V1: 0.51, V2: 0.61, V3: 1.18, V4: 0.55
Mine: TP22: 1.00V, AV-: 0.64V, AV+: 1.30V, +3.3: 0.23V, +5: 1.80V, V1: 0.58, V2: 0.60, V3: 1.30, V4: 0.66 V+: 8.6V
Q1c=0.0V Q2c=6.21V
Q1b=6.3V Q2b=0V
Q1e=6.3V Q2e=0V
Voltage at bottom of R40 = 0V
L1, L2, L3, and L4 are not Open - all have resistance

With L3 disconnected:
TP22: 3.30V, AV-: 0.00V, AV+: 0.00V, +3.3: 0.00V, +5: 5.00V, V1: 0.00, V2: 0.00, V+: 8.6V
Resistance from DGND to:
AV-: 1.75k
AV+: 4.30K
+3.3: rising to 15.8k
+5: 4.09k

Pin5 on the switches are connected to AV+ and are not shorted to GND
8.17V at base of R38

Can you provide some assistance on what I should check for next ?
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Joined: Fri Jan 25, 2019 10:10 pm

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