Texasbluezman
Member
I've been looking on here for a couple of months, trying to figure out WTF was wrong with my amp. I got really discouraged. I had never soldered on a pcb before, and was a little nervous about trying. I got a really good deal on this amp and a 1960BV cab. $500. The cab is worth that, but without a head, it's just a bunch of speakers. This head is a 1999 model.
About a month ago, another TSL 100 head come up on CL for cash or trade. I jumped on it. Got rid of a combo, that I didn't use, and some cash, and I was the owner of another head. A 2006 model.
So now I felt better about taking my head apart to see if I could fix it. Not the head on my body, that one's totally f@#$ed.
I read various threads on here for 2 weeks straight. Still being a little reluctant. I started by labeling the wiring and taking out the mother (tube) board. I planned on doing the bias drift mod, and a few others. See, the problem was, that I would turn the amp on, let the tubes warm up, flip it off stand by, play it at bedroom levels, with VPR off, and after about 5 mins, the volume would just fade away to nothing. After about 5 mins, it would come back on from 1 to sometimes 5 mins, and repeat. It seemed like a heat related issue. Oh, and it was biased at 85mv.
All mods were done to the motherboard (MB). I plan on doing more to the MB and the OD board later, but it sounds really good for now.
Here's what I've done so far:
C43, C44- 22uF, changed from 50v to 100v
C6, C7- changed from .022uF to .068uF, 630v
R7, R10, R66, R70- changed from 220 ohms to 5.6k ohms. 1 watt metal film.
C46- 22pF, changed from 500v to 1KV
R2- 100k ohms, changed from 1/2 watt to 2 watt
R3- 82k ohms, changed from 1/2 watt to 2 watt
All of the mods can be found on this forum. If these mods didn't work, tubes were the next thing to buy. I don't know how old they are. It has Svetlana's in the power section and no names in the preamp. The 2006 has a full set of JJ's in it. They both sound great now, with a few minute differences. Most of the time I like the '99 more than the '06. Can't really explain it, but it sounds better to my ears.
Also, I tried to fix the footswitch on the '99, and was unsuccessful. I had a thread going about it, but I gave up. I then built my own 2 button footswitch. Again, from a thread found here. The '06 head had a working footswitch, but I really like my 2 button. Takes up less real estate. I don't use the switches for the reverb or the effects loops anyway. Gonna try to upload a couple of pics.
Thanks to everyone here on the forum. Keep up the outstanding work. Thanks, also, for putting up with the countless noobs like myself! Peace!
About a month ago, another TSL 100 head come up on CL for cash or trade. I jumped on it. Got rid of a combo, that I didn't use, and some cash, and I was the owner of another head. A 2006 model.
So now I felt better about taking my head apart to see if I could fix it. Not the head on my body, that one's totally f@#$ed.
I read various threads on here for 2 weeks straight. Still being a little reluctant. I started by labeling the wiring and taking out the mother (tube) board. I planned on doing the bias drift mod, and a few others. See, the problem was, that I would turn the amp on, let the tubes warm up, flip it off stand by, play it at bedroom levels, with VPR off, and after about 5 mins, the volume would just fade away to nothing. After about 5 mins, it would come back on from 1 to sometimes 5 mins, and repeat. It seemed like a heat related issue. Oh, and it was biased at 85mv.
All mods were done to the motherboard (MB). I plan on doing more to the MB and the OD board later, but it sounds really good for now.
Here's what I've done so far:
C43, C44- 22uF, changed from 50v to 100v
C6, C7- changed from .022uF to .068uF, 630v
R7, R10, R66, R70- changed from 220 ohms to 5.6k ohms. 1 watt metal film.
C46- 22pF, changed from 500v to 1KV
R2- 100k ohms, changed from 1/2 watt to 2 watt
R3- 82k ohms, changed from 1/2 watt to 2 watt
All of the mods can be found on this forum. If these mods didn't work, tubes were the next thing to buy. I don't know how old they are. It has Svetlana's in the power section and no names in the preamp. The 2006 has a full set of JJ's in it. They both sound great now, with a few minute differences. Most of the time I like the '99 more than the '06. Can't really explain it, but it sounds better to my ears.
Also, I tried to fix the footswitch on the '99, and was unsuccessful. I had a thread going about it, but I gave up. I then built my own 2 button footswitch. Again, from a thread found here. The '06 head had a working footswitch, but I really like my 2 button. Takes up less real estate. I don't use the switches for the reverb or the effects loops anyway. Gonna try to upload a couple of pics.
Thanks to everyone here on the forum. Keep up the outstanding work. Thanks, also, for putting up with the countless noobs like myself! Peace!