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#21
General Questions / Re: Rabbit Hole Problem
Last post by pedalbob - September 17, 2024, 01:04:33 AM Ha thanks ! ... I have a 2016 board so was using that build document (catching up on some that I never build and have been sitting around).
In the meantime I measured the voltages on my actual big muff and they are similar.
I think I'm getting close to my problem. I have roughly 4+ volts at collectors on Q2-Q4 but the collector on Q1 is over 8 volts and 3 of the emitters are measuring 0 volts.
guessing something around R6/C2/R4 not right. Will poke around some more and check values in the morning.
In the meantime I measured the voltages on my actual big muff and they are similar.
I think I'm getting close to my problem. I have roughly 4+ volts at collectors on Q2-Q4 but the collector on Q1 is over 8 volts and 3 of the emitters are measuring 0 volts.
guessing something around R6/C2/R4 not right. Will poke around some more and check values in the morning.
#22
General Questions / Re: Rabbit Hole Problem
Last post by jwin615 - September 16, 2024, 08:36:09 PM #23
General Questions / Re: Rabbit Hole Problem
Last post by pedalbob - September 16, 2024, 07:51:04 PM Thanks jwin615
Unfortunately the build doc for this one has no voltages but I have my actual Big Muff apart and will check its voltages tonight.
Yes I was using a signal probe and getting no signal after C1 and just about 1/2 of the loudness going into C1 and coming out of R2. When I probed my actual Big Muff I have signal all over the place (Q1-Q4, clipping diodes, etc.) so I know something is drastically wrong.
Will report back voltages if I find anything.
Unfortunately the build doc for this one has no voltages but I have my actual Big Muff apart and will check its voltages tonight.
Yes I was using a signal probe and getting no signal after C1 and just about 1/2 of the loudness going into C1 and coming out of R2. When I probed my actual Big Muff I have signal all over the place (Q1-Q4, clipping diodes, etc.) so I know something is drastically wrong.
Will report back voltages if I find anything.
#24
General Questions / Re: Rabbit Hole Problem
Last post by jwin615 - September 16, 2024, 01:59:13 PMMake sure you didn't mix up 100k and 100R resistors in the first stage?
I'm assuming you have an audio probe setup. Are you sure you're losing signal before Q1? I like the break up circuits for initial probing. So, I would probe the collector of each transistor.
Do your transistor voltages look similar to those in the build doc?
I'm assuming you have an audio probe setup. Are you sure you're losing signal before Q1? I like the break up circuits for initial probing. So, I would probe the collector of each transistor.
Do your transistor voltages look similar to those in the build doc?
#25
General Questions / Re: SMD version of MPSA18
Last post by jwin615 - September 16, 2024, 01:43:46 PMCould use mmbt22222
#26
General Questions / SMD version of MPSA18
Last post by garfo - September 16, 2024, 06:44:26 AMI have been looking for an SMD package for the MPSA18 and I cannot find anything. Has anyone had any luck with finding this as an smd package?
#27
Tech Help - Projects Page / Re: MadBean Orifice (Openhaus)
Last post by MIYTADJ - September 16, 2024, 03:39:04 AMMadBean
I have a question for you about the orifice. Would 2n1308 ( a higher gain than 1306 ) work with this circuit? I know I can Socket and see but rather than spend 20 bucks for 2 transistors and plus shipping I figured I'd ask first. But just going off the fact the 1308 is more gain than 1306 (in my head I think well if 1306 makes it sound that chunky and crunchy more gain more crunch but with my limited knowledge I do know that's not always the case (the more gain more crunch thought)So I thought maybe you could shed some light on that question before I buy them.
Cause I did have some 2n1304 I tried and I only got a mild overdrive.
Thanks for your time and layouts
I have a question for you about the orifice. Would 2n1308 ( a higher gain than 1306 ) work with this circuit? I know I can Socket and see but rather than spend 20 bucks for 2 transistors and plus shipping I figured I'd ask first. But just going off the fact the 1308 is more gain than 1306 (in my head I think well if 1306 makes it sound that chunky and crunchy more gain more crunch but with my limited knowledge I do know that's not always the case (the more gain more crunch thought)So I thought maybe you could shed some light on that question before I buy them.
Cause I did have some 2n1304 I tried and I only got a mild overdrive.
Thanks for your time and layouts
#28
General Questions / Re: Rabbit Hole Problem
Last post by pedalbob - September 15, 2024, 03:20:37 PMThanks.
Ok reflowed joints with no change.
Just for yucks I pulled the downstream leg of R2 and signal volume increased when I touched the loose leg so not a bad R2 resistor. Re installed and pulled C1 as well and also signal now passed to C2 (and it measeured ok with my analyzer) so not a bad C1 either. So seams like it is feeling downstream circuit as a large impedence.
Also double checked the pinnout on the 2N5088's I used from the ones I had left (same batch) and fine.
Going to check some back to back voltages based on the stock EHX Big Muff I have unless anyone else has some beter idea. I am getting good 9v from the Power connections and thru D5 etc.
Ok reflowed joints with no change.
Just for yucks I pulled the downstream leg of R2 and signal volume increased when I touched the loose leg so not a bad R2 resistor. Re installed and pulled C1 as well and also signal now passed to C2 (and it measeured ok with my analyzer) so not a bad C1 either. So seams like it is feeling downstream circuit as a large impedence.
Also double checked the pinnout on the 2N5088's I used from the ones I had left (same batch) and fine.
Going to check some back to back voltages based on the stock EHX Big Muff I have unless anyone else has some beter idea. I am getting good 9v from the Power connections and thru D5 etc.
#29
Build Reports / Re: New Aion L5 Preamp
Last post by Lovebandits - September 15, 2024, 08:22:59 AMGordo, it looks amazing, bet it sounds just as good as it looks!!
#30
General Questions / Re: Rabbit Hole Problem
Last post by mauman - September 15, 2024, 03:56:44 AMIn your photo, there's not much solder on the north leg of R2, and the same with a lot of the other components. I think I'd reflow each of your solder joints and add a bit more solder, there should be a small fillet around the legs of each component and many of them don't have that (R8, R5 jumper, etc), which could indicate cold joints = no connection.