Messages

Thanks
BK

Bengt,

Thanks for you response. Looking at the pcb traces / schematic in the PDF file if I don't jumper the 2 round holes on the fat switch then R6 and R21 won't be in the circuit. Are these resistors not necessary if I don't have the switch? I must admit I can build better than I understand these circuits so I just want to be sure.




Looking at the traces for the AS/SYM switch I need to jumper the two round holes as well.

Thanks,
BuzzKing

I am building a Green Bean for a friend of mine. He swears by his vintage TS9 so I want to make this a "better" TS9. So I want to make some modifications. I have some thoughts and some questions on how to accomplish this.

1) Replace R15 with 470 ohm resistor
2) Replace R16 with with 100K resistor
3) Omit AS/SYM switch and extra diodes. Which pads on the switch do I jumper - the two round pads or the middle round pad and the square pad? Which diodes do I omit?
4) Omit FAT switch and extra capacitor. Which pads on the switch do I jumper - the two round pads or the middle round pad and the square pad? I can omit C5 correct?

Any other suggestions? Thanks in advance.
BuzzKing

Thanks, I had searched mouser but did not come across that one. I would prefer a boxed cap as shown in the picture on the build doc but the one you cited will work fine. Thanks again.

Just ordered the Green Bean board. Starting to source and order components. I am having trouble finding a 120n MBF capacitor. Any thoughts on where to order or alternative capacitor?

Thanks,
BuzzKing

So I tested all the components on the board. The ones Clayford pointed out were indeed wrong as well and R10. So it looks like when I was populating the 47k resistors I picked up the wrong bag. Lesson learned. I will check codes and meter all parts before placing on any board. Good insurance.

After replacing those resistors, the board works perfect. Unity volume and nice sounding chorus.

I did a quick run of voltages across the ICs:
Listed as 1 2 3 4 5 6 7 8
IC1 6.77 6.77 6.77 1.5mV 6.77 6.77 6.77 9.43
IC2 *** 4.70 *** 1.3mV 4.7 4.7 *** 9.43 (*** = highly variable)
IC3 9.32 4.76 1.4mV 4.8 0.42 3.22 0.625
IC4 9.32 4.80 5.99 0.625 1.4mV 4.76 6.14 6.14

Is it odd that there is ~1.3-1.4 mV at ground throughout the board?

BuzzKing

Thanks,

Most of my resistors are 5% tolerance, some 2%. I will measure some 2.7 and 3.3 and see if one is actually close.

I do have plenty of 1.5k so I can use 2 of those.

I will likely socket the position and the next time I have to order from Mouser will get some 3k.

Rick

I am having trouble locally sourcing the 3 K ohm resistor (R48) on my Stage Fright build. I do not need to make any orders for other parts right now and really don't want to order a 5 cent part. Can I use a 2.7 K ohm or a 3.3 K ohm resistor instead? I have plenty of those on hand. If so which would be best to use.

Rick "BuzzKing" Kienle

Thanks for the welcome to the forum.

I have built several relay based bypass strips / pedals using boards from AMZ. I also built an AMZ Q&D compressor that passes a signal but I am not sure it works correctly. Then I built a test rig because I could tell I was gonna get real into this DIY pedal thing.

I have also modded several Boss and Ibanez pedals using Monte Allums mods. In case your interested you can check out his site. Great guy and great mods to get your feet wet with DIY pedal work. http://www.monteallums.com/

The Pork Barrel is my first attempt at a more difficult build.

I checked the resistors you mentioned both with the codes and with an ohm meter and you are correct. I was off by a decimal point. At this point I am going to go through the BOM and test every component on the board and will replace the incorrect ones.

I will report back on my progress in a few days cause I will only have a little time in the evenings to do the work.

Thanks a ton for all your help.

Rick "BuzzKing" Kienle

BTW, all my tests were done with black lead of meter on ground and red lead probing the chips. Is that correct?

Thank you so much for all the info. Also, the pictures of the finished board will be a good resource. I did copy your spreadsheet. I kept a blank one to use for othe projects. By the way, what is are vias?

I hope its as easy as the wrong "47" resistors. I only measure resistors that come out of unlabeled bags. It may be that I ordered wrong or they were bagged wrong. Or maybe I placed them in the wrong slot in my parts bin.

So later tonight, or over the next few evenings, I will take a much closer look and measure all the resistors and caps on the board. I will replace any that are wrong and then repeat the voltage measurements.

I will post a new pic after appropriate repairs. If that doesn't work I acually have a 4558 chip I can try.

Thanks much,
Rick "BuzzKing" Kienle

I just finished populating a Pork Barrel PCB. This is the latest version built from a purchased PCB.

I have not boxed it yet. The test is done with a test rig.

Everything seems to work fine except the output with the effect engaged is roughly 50% quieter than when the effect is bypassed at the test rig. Both pots seem to do what they are supposed to and the effect actually sounds quite good, just much quieter compared to when bypassed. I am testing other boards at the same time so I know its not the test rig.

I built this board with the following modifications:
1) Added Monte Allums mods: C1 = 0.1 uF film cap; C8, C13, C17 = 0.047 uF boxed film caps; C2, C7, C12 = 1 uF tantalum caps; IC1 = OPA2134PA
2) I have socketed R9, R39, C18, C17, and R27 so that I can eventually test tonepad mods and the LFO indicator / depth mod. Currently the stock values are in place. No mods have been tried at this point.
3) I have omitted D4 as I am using the M3101/M3007 chips. Does this need a jumper? Or just omitted?
4) I have omitted R1 and will only add it if needed after boxed. Once again does this need a jumper? Or just omitted?

I have checked and do not visually see any solder bridges or cold solders. I have checked and double checked the values of the components. I have tested voltages (see pic below). I have tried 2 different sets of ICs with similar results and voltages.





I don't know what to expect for the voltages. There are some wonky readings on TL063 3,5,7. The voltage on  pin 8 of the M3101 seems low but again I don't actually know what is correct for this build. It is also interesting that at ground points there is a small voltage ~1.1 - 1.3 mV. Does this indicate an issue?

Any help is greatly appreciated.

Thanks,
Rick "BuzzKing" Kienle