Repaired the left channel on this receiver KR-6170. I would like to check/set the Bias/Idle Curent. The Service Manual I found online is a bit confusing. Is anyone familar with the Bias/Idle Current setting procedure?
I have checked the voltages as described above under Testing Procedures. Voltages seem to be acceptable. Q2: 68.8 VDC, Q3: 31.1 VDC, Q4: 31.7 VDC, Q5: 68.8 VDC.
The Idling Current procedure on the right side has me a bit confused. It says to test at collector of transistors. I'm familar with testing across emitters or emitter resistors but not across collectors. I tried testing with 1 probe on the collector of Q2 and the other probe on the collector of Q3 and got a pop in the speaker and it blew the fuse in the DVM. The DVM was set on 200mA. I did not have a dummy load, audio generator, or oscilloscope as described in steps 1 & 2. The instructions make no sense to me.
The receiver plays and doesn't sound too bad The TO3 outputs don't seem to be running hot, so the original settings on VR1 VR2 must be in the ballpark.
Anyone willing to make suggestions?
Thanks
I have checked the voltages as described above under Testing Procedures. Voltages seem to be acceptable. Q2: 68.8 VDC, Q3: 31.1 VDC, Q4: 31.7 VDC, Q5: 68.8 VDC.
The Idling Current procedure on the right side has me a bit confused. It says to test at collector of transistors. I'm familar with testing across emitters or emitter resistors but not across collectors. I tried testing with 1 probe on the collector of Q2 and the other probe on the collector of Q3 and got a pop in the speaker and it blew the fuse in the DVM. The DVM was set on 200mA. I did not have a dummy load, audio generator, or oscilloscope as described in steps 1 & 2. The instructions make no sense to me.
The receiver plays and doesn't sound too bad The TO3 outputs don't seem to be running hot, so the original settings on VR1 VR2 must be in the ballpark.
Anyone willing to make suggestions?
Thanks