Eros VDC

[bucketofguts]

1A  219
2B 218
OA 156
OB 215 ,.....?
OC 95
OD 83
OkA 97
Okb 83
OkC 1.47
Okd 2.61   ....?


-C4S has 2 leds not lit.

[Paul Birkeland]

Most issues like this come down to soldering issues on the front C4S board.  I would reflow all the joints except the ones for the LEDs themselves. 

[bucketofguts]

Copy that and thnk you very much.

[bucketofguts]

After reflowing..................

A1 220
1B 218
OA 217
OB216
OC 212
OD212
OkA O
OkB 0
OkC 1.07
OkD 0.8


Lost two more leds.

[Paul Birkeland]

The 0V on OKA and OKB would tend to indicate wires not hooked up or some kind of broken connection with the 6922 socket. 

[bucketofguts]

Will be checking. Thank you very much.

[bucketofguts]

Third time.......

1a 219
1B 218
OA 154
OB 216
OC 97
OD 84
OkA 98
OkB 83
OkC 1.9
OkD 2.70

All leds will work. Just not all eight at the same time. I changed out the 6922 valve for these last voltages.  Two leds that did not light during first check came on the latest test leds near B! and OB test points not lit on latest test. They were on the first check.

[Paul Birkeland]

A fresh 6922 is a good idea, as faults in this circuit can damage that tube.  You are getting closer but OB and IB are still stuck at about the same voltage, which would have me reheating the center leg of the MJE350 closest to OB.

[bucketofguts]

Side note. I have tries a few 6922s. all 4 leds will lite for a few seconds then the two  leds Ii mentioned slowky go dim. will try your advice. Thank you for your time Sunday in the pm.

Salute,

b~

[bucketofguts]

Same issue with the DCV.  Plug in and eight lights come on and a second or two two dim and go out. The four leds one the other board light and stay lit  a few seconds later.

[Paul Birkeland]

You can try a fresh 2N2222 on the side that isn't working.  I find somewhat often that soldering problems will take that part out once the amp is powered up, and fixing the solder still leaves a damaged transistor.

[bucketofguts]

I will touch base with E tomorrow via email  on the part/ s. Thank you for keeping me in the loop. Oh yea it is Sat. not Sun.I still thank you very much!

Cheers,

b~

[bucketofguts]

I ordered a new C4S board and all new parts + an extra MJE350 and a 2N222 to put in my original board to try.. Hearing that the circuit can damage a 6922 hurts. I been putting Amperex American white lable PQ's in rotation each time I reflowed/ reheated. Have Mercy!

[bucketofguts]

New C4S board  and all ne parts.

A1 219
1B 218
OA 159
OB 216
OC 154
OD 97
OKA 152
OKB 95
OKC 12.0
OKD 16.0

All leds are lit. the decimal point on the last two values are what I saw. The last two values my eyes may have been playing tricks. Black wite between the 174 uf resistors broke at some time during/after test it is fixed now.

Thank you for your time.

[bucketofguts]

VDC this morning: 2 times changed the 6922 for the first and the er86 for the second.

!A 220     233
!B 218     233
OA 135     135
OB 216     231
OC 115     116   
0D 85     86
OKA 116     116
OKB 84     84
OKC 2.1     2,0
OKD 2.5     2.5

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