Procrastinator Help (Boss SG-1 Clone)

[keilb]

So I had bought the Procrastinator about three years ago while I was in school for electrical engineering, and I was unable to get it to work. After much troubleshooting it still didnt work. I recently found it again and decided to not use sockets on the transistors, but while desoldering the sockets I broken some soldering pads, so I ordered a brand-new Procrastinator PCB and just started from scratch.

This time I tested all my transistors and the JFET to ensure they work and to 100% make sure, while also double checking with the datasheets, that the pins were correct. With also looking at the PCB itself and following the traces while double checking with the schematic, the 2SK30A is in-fact backwards on the PCB outline print. Okay, I got that sorted out.

Now I double checked that each resistor and cap were the right value and that the electrolytics were in the right polarity on the PCB. I soldered in the transistors with extreme care and only hit them quick to get the solder on, nice clean and shinny solder joint (no cold joints anywhere).
I decided to still use a socket for the op-amp tho, but ensured that the connections where good.
I even bought the little PCB 3PDT Breakout Board for the switch to furthermore rid of potential errors.
I have also put some plastic sheeting on the bottom of the PCB so no shorts happen when it is against the pots.

So, it's all built and I plug it in. The LED turns on just fine, but there is no sound. I actually realized if I turn the Sensitivity knob all the way up and play really hard I get some stuttering sound from my amp. Im going to double check the op-amp and pots, but they havnt been misused at all.

Wondering if anyone did this build and what they have noticed or anything. Any help would be great!

Thank you for reading my dumb of a post! I tried to give as much detail as I can haha.

 

[keilb]

No I guess I just had the trimmer at 12-o-clock. Ill try to adjust it, where did you have yours by chance?

Yeah I read a review where it doesnt do too much. Have you played an original SG-1? Is it the same?

 

[PJS]

I have used a boss digital clone of the SG-1 in a multi-effect board and really liked it. I did move to using a volume pedal to have a bit more control over the timing of the swells, but the digital copy at least worked well.

 

[jimilee]

I built one. I had to turn the swell pot all the way up for it to do much. There are a few tweaks that help a little.

 

[Diynot]

Built one recently without issues. I believe my 2sk30s are in matching the screen print. I think I have the trimmer about midway. A very underwhelming effect. Plays a little nicer if you have some sort of compression in front of it.

 

[scott3t]

So I had bought the Procrastinator about three years ago while I was in school for electrical engineering, and I was unable to get it to work. After much troubleshooting it still didnt work. I recently found it again and decided to not use sockets on the transistors, but while desoldering the sockets I broken some soldering pads, so I ordered a brand-new Procrastinator PCB and just started from scratch.

This time I tested all my transistors and the JFET to ensure they work and to 100% make sure, while also double checking with the datasheets, that the pins were correct. With also looking at the PCB itself and following the traces while double checking with the schematic, the 2SK30A is in-fact backwards on the PCB outline print. Okay, I got that sorted out.

Now I double checked that each resistor and cap were the right value and that the electrolytics were in the right polarity on the PCB. I soldered in the transistors with extreme care and only hit them quick to get the solder on, nice clean and shinny solder joint (no cold joints anywhere).
I decided to still use a socket for the op-amp tho, but ensured that the connections where good.
I even bought the little PCB 3PDT Breakout Board for the switch to furthermore rid of potential errors.
I have also put some plastic sheeting on the bottom of the PCB so no shorts happen when it is against the pots.

So, it's all built and I plug it in. The LED turns on just fine, but there is no sound. I actually realized if I turn the Sensitivity knob all the way up and play really hard I get some stuttering sound from my amp. Im going to double check the op-amp and pots, but they havnt been misused at all.

Wondering if anyone did this build and what they have noticed or anything. Any help would be great!

Thank you for reading my dumb of a post! I tried to give as much detail as I can haha.

Mine works but distorts and craps out as the input signal fades. The "procrastination" is really short. Also a bit of background noise. Nothing like the real SG1

 

[scott3t]

Mine works with a very short fade in time(compared the the SG1 and Behringer clone) and it crackles out as the signal fades as well. Tried the trim pot at several positions with little change. Any suggestions?

 

[drgonzo1969]

Im having the exact same issue. did you ever solve this one?

 

[Guardians of the analog]

I've built a couple of these and it may be that the jfet is out of spec. Like many through hole jfets especially the 2sk30a, what's left has been picked thru and may not be in the optima range. you may have to audition multiple jfets. of course, that assumes that nothing else is the culprit.

 

[drgonzo1969]

That was my suspicion too. I will have to bust out the DMM later and see what is going on. What voltages should I look for on the 2sk30a

 

[Guardians of the analog]

That was my suspicion too. I will have to bust out the DMM later and see what is going on. What voltages should I look for on the 2sk30a

I checked the data sheet for the 2sk30a before I installed and picked one in the middle of the range for specs. Actual in board voltages I have not taken. I can check voltages at the IC as well for you later today after work.

 

[Guardians of the analog]

That was my suspicion too. I will have to bust out the DMM later and see what is going on. What voltages should I look for on the 2sk30a

I hope it's easy enough to read. I measured all transistors and labeled it leg 1-3 to make it easier. Leg one being on the left. On Q5/6 the voltages vary by going down in voltage.

 

[drgonzo1969]

Hell ya. Thanks so much for doing that. As soon as I'm done cooking dinner for the fam im going grab the DMM and run through the transistors and see what I see. I really appreciate your help. good looking out.

 

[drgonzo1969]

ok, all my voltages lined up except for.... you guessed it... the 2sk30a (Q2). I got 2.3v on the 2nd leg instead of 5.2v. Im guessing this is the culprit as you predicted. Im going to swap it out for another 2sk30a tomorrow and see if that does the trick