Hi there, I would like to ask for a help and assistance.
I measured totally wrong voltages inside G3. I hate to say it, but by my unfortunate mistake I caused a tiny spark/short on V1-1 when I started to measure
Could you help me to troubleshoot please? Thank you for any help,
Janek D.
I UPLOADED SOME Additional photos (inside the amp and measurements table)
No. | Checkpoint | Should be | Is | Comment |
1 | Wall plug socket* | 230 VAC | 235 | Power Supply input voltage at start of measurement |
2 | V3-4/5 | 6,5 VAC | 6 | Heater voltage at tube socket V3 - between Pin 4 und 5 |
3 | BR1- ~/~ | 208 VAC | 212 | Input of bridge rectifier BR1 - between the two "~" lugs |
4 | (A) lug 21 t ** | 260 VDC | 320 | Supply voltage to V3 |
5 | (B) lug 18 t | 237 VDC | 317 | Supply voltage to V2 |
6 | (C) lug 18 b | 225 VDC | 315 | Supply voltage to V1 |
7 | V1-1 | 225 VDC | 315 | At plug socket |
8 | V1-3 | 81 VDC | 237 | At plug socket |
9 | V1-6 | 105 VDC | 296 | At plug socket |
10 | V1-7 | 1,2 VDC | 0 | At plug socket |
11 | V1-8 | 110 VDC | 0 | At plug socket |
12 | V2-1 | 185 VDC | 308 | At plug socket |
13 | V2-3 | 50 VDC | 0 | At plug socket |
14 | V2-6 | 166 VDC | 312 | At plug socket |
15 | V2-8 | 3,0 VDC | 0 | At plug socket |
16 | V3-1 | 251 VDC | 321 | At plug socket |
17 | V3-6 | 254 VDC | 321 | At plug socket |
18 | V3-3+8 | 10,5 VDC | 0 / 0 | At plug socket, please measure at both lugs! |
19 | (R13) lug 10 b | 47 VDC | 0 | an R13 unten |
20 | Wall plug socket* | 230 VAC | 236 | Power Supply input voltage at end of measurement |