D'Lite completed, but not working right - Please help!!!
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D'Lite completed, but not working right - Please help!!!
Well, I just finished my D'Lite build (followed Normster's layout and schematic exactly), but I'm running into a pretty serious problem. The clean channel works just fine, but the OD just won't behave. When on OD, if I turn the preamp volume up past about 9:00, the sound becomes very fizzy before just dying off. I'll play a note, and it will die immediately - after a few more seconds, no sound will come out of the amp at all (interestingly enough, that includes hum - I can have the master up, and no noise whatsoever will come through the speaker). What really gets me, though, is that if I turn the volume back down to 9:00 or lower, the problem doesn't go away - I have to actually switch back over to the clean channel and then switch back to OD for any sound to come out again. As long as I keep the volume below 9:00, the OD drive and level controls work perfectly, so I'm pretty sure the problem is solely on V2a; I'm thinking there might be a build-up of charge on the grid that's causing the tube to shut down. Anyway, I've attached some pics of the build. Any advice at all would be great!
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Re: D'Lite completed, but not working right - Please help!!!
Fharwath,
Do you have your 100k trim pot connected to ground and the 220k resistor under the circuit board? If not your missing those connections.
Do you have your 100k trim pot connected to ground and the 220k resistor under the circuit board? If not your missing those connections.
Re: D'Lite completed, but not working right - Please help!!!
resophonic1,
I did connect the 220k underneath the board, but I completely forgot to connect the ground I'll fix it and let you guys know how it works.
Thanks!
I did connect the 220k underneath the board, but I completely forgot to connect the ground I'll fix it and let you guys know how it works.
Thanks!
Re: D'Lite completed, but not working right - Please help!!!
That's the cause of your problem! The OD1 tube had no chance, to bias itself through a grid resistance to ground, the previous coupling cap had no chance, to drain & recharge itself --> blocking distortion with following cut-off!fharwath wrote:... but I completely forgot to connect the ground
Larry
Larry's Website now with included Pix's Gallery
Re: D'Lite completed, but not working right - Please help!!!
Alright, I grounded the trim pot and fired it up and it was SMOKIN!!!
However, after about an hour of playing, I heard a "pop" (I was playing pretty loud, around 1:30 on the master) and suddenly there was this weird "gargle" whenever I would play a note - I'm thinking a cap blew...
Update: Yeah, it was the cap on the rectifier board (different value than called for, I had to change the bias circuit because the PT I used did not have a 45v tap) - I had it in backwards (see pictures). Whoops! Weird things happen when you're working at 2:00 AM
However, after about an hour of playing, I heard a "pop" (I was playing pretty loud, around 1:30 on the master) and suddenly there was this weird "gargle" whenever I would play a note - I'm thinking a cap blew...
Update: Yeah, it was the cap on the rectifier board (different value than called for, I had to change the bias circuit because the PT I used did not have a 45v tap) - I had it in backwards (see pictures). Whoops! Weird things happen when you're working at 2:00 AM
Re: D'Lite completed, but not working right - Please help!!!
Congrats on the build. Looks nice and clean. Yes I've made the mistake of not grounding a trimmer before and had the same issue, glad you got it fixed.