Looks like the voltages indicated something was wrong from the first step. You want to take care of that before going any further otherwise you will damage other parts. I followed step by step exactly as written on TSE checkout process. Step 1 should show negative voltage from both B+ and B-.1) w/ no tubes in,
B+ = 0v
B- = 0v. R6 is bad
Output tube filament supply left =4.96v , right =4.96v
2) w/ rectifier tube in,
B+ =474v
B- = 0v. R6 is bad
Output tube grid to ground left = 0v , right =0v
3) w/ rectifier tube and input tubes in,
B+ =474v
B- =0
Input tube plate to ground left =1.2v , right =1.2v
4) w/ all tubes in and set the output tube bias,
B+ =474v
B- =0
Input tube plate to ground left = 1.2v, right = 1.2v
Well to close this out.....
The amp is alive and well, my issues were due to using an incorrect BOM. Lessons learned:
1 - always do your own BOM and check it twice.
2 - U1 requires SIGNIFICANT heat sinking. Use heat transfer epoxy to assure good bonding.
3 - Use a 5w value for R5
4 - It certainly was worth the drama.
The amp is alive and well, my issues were due to using an incorrect BOM. Lessons learned:
1 - always do your own BOM and check it twice.
2 - U1 requires SIGNIFICANT heat sinking. Use heat transfer epoxy to assure good bonding.
3 - Use a 5w value for R5
4 - It certainly was worth the drama.
How long after power up did you measure? I takes about 10 - 15 minutes for that to go up and stabilize.I need to tweek some of the values a little on the driver portion of the board, as Im only getting about 146v on the plates of the drivers.
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