Solo100
Hi all!
So I got home yesterday and my tubes were ready and waiting for me! Unfortunately im getting nothing out of the amp. So am at a bit of a loss as to where to go now.
Here are the voltages I got a couple of weeks ago
Mains 122
Standby switch 497
V1 - P1 359
V1 - P6 359
V2 - P1 350
V2 - P5 350
V3 - P1378
V3 - P6 378
V4 - P1 378
V4 - P6 378
V5 - P1 378
V5 - P6 378
V6-V9 P3 495
Today though I checked the voltages and am getting 525 across pretty much every thing except the mains which is steak at 122v
B+ 525
B+2 525
B+3 525
So something is not right here. I put the valves In and got nothing. They aren’t getting war at all. And im getting no sound from it at all..
Any thoughts as to where I can start looking?
Regards
Phil
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When faced with no sound in any amp, new build or old, I use an electronic stethoscope to check for signal at various points in the signal chain.
Take a pair of clip leads, cut one and put a 600V cap in line, the value is unimportant, anything from .001 to .1uF will do. I have a 1/4" plug on one end, the clip lead with the cap goes to hot, the other to ground.
Connect a signal source tot the input, connect the jack on the stethoscope to another amp. Connect the clip lead ground to chassis ground, and use the lead with the cap to trace the circuit.
Start at the input and make sure you're getting signal from the input jack to the grid of the first stage. If that's good, check at the plate of that stage. I don't know the SLO all that well, but just follow the schematic until you have no signal, there's your problem area.
Good luck