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due to a wierd/tired arse ordering error, I got from cabintech 3 mn3007 and 2 mn3005's when I wanted to order 1 mn3k7 and 4mn3k5. now the 3k5 is gone from everybody remotely trustworthy except amplified parts and... it's only 3ish dollars more to get a v3205/3102 setup(4 chips) than what the man in AZ is asking for a single 3k5. can I swap on 1 of these boards ? how much alteration would it take like a regulator/zener swap?

I was wondering IF that really is the intended spot for the free mica cap, c24 is a 1uf alum electrolytic, the leads aren't even remotely close. I have a few days.. been slowly goign through my parts bin to see what I can skip ordering from Digkey or mouser.

Now I'm trying to find where my volume dies off on this 1, I'll get it out of the box if can't find the problem on the front side.




ic 1                ic2          ic7            IC 3      
1: 4.7            9.08        4.54    9.01~3
2  4.7        4.47        4.55   4.48
3  2.34        4.04        4.54   4.35~48
4  0                1.1ma     0           4.28~49
5  4.14        0            4.13   4.38~50
6  4.56        ~4.36-47  4.55   4.24~48
7  4.40~1       ~4.01     4.55   4.5
8  9.08         ~4.0      9.09   0
9               4.26~48
10               4.3~5
12               4.29~49
13               0
14               4.24~49
15               4.29~49
16               0
   ic 4        ic5              ic6
1  4.5        sweep      0
2  4.5        4.01~13           sweep
3  2.9~7.04     sweep      sweep
4  0                8.98~9.01   0
5  4.35~50     0              9.08
6  0                 0                   9.08
7  0                7.71~76           sweep
8  0                sweep      9.08
9  0                sweep
10 0                sweep
11 0                0
12 0                4.08~12
13 0                4.06~4.22
14  9.06             sweep

Rough guessing that w/e is causing the low voltage at !C 1, pin 3 is the culprit. I admit I have no clue how to bleep bleep check a capacitor but the resisitors were in the 1% range, vishays or koa speers. pay no attention to the black on the trim pots, that was sharpie so my tired arse could tell where 50% was. the middle pin of the range pot IS filled in, that's just a shadow/dip in the solder pool.

Ok, now I'm trying to see wtf I did to this 1. I hope nothing fried when I put the previous wrong 470uf cap in (the 4v "popcorn") My voltage readings were either 18.3 or fast fade from 5 to .02 before I put the IC's in. I put the chips in sequentially, 4558's(cheapest to replace) followed by the 1458 then the 4013, then the 4049 aand finally the mn3k7, nothing smoked but all the pins jumped to .03 lower than the positive pin on the power jack. I socketed C23, has 2 120's in for now. I have sound on bypass, goes utterly dead on except teh spiked power on the ic pins turned on and the led is off. I ran a continuity test on the 3pdt and got connection where it's supposed to be.

Now wtbf I miss?

This is a tale from the weird side. Got my tourbus assembled, voltage readings no were close to MB's but nothing off the scale. Said screw it put op amp chips in, nothing smoking(yes I know the smell after that TS build TO well...)ok, place the 571 and 4047.. still nothing cooking hot. place the 3005's... no need yet for the extinguisher.
I run a signal through, I get an effect without distorting!! Now it gets weird.... run away self oscillation from to much feedback, no big but does it from 1 o'clock onwards clockwise. I play with some other settings and I get a result similar using a Boss Slo pedal/swell effect but I can hear the pick strike.  And the punchline I have YET to adjust a single trimpot on the daughter board, it's how they came from Mouser
Any clue to the cause? go with the 'just match voltage on X pins via the 2 bias/gain trimmers or just leave it alone and make some funky sci fi BGM?

I'll post a pic later of the guts, most of my DMM readings were like 15.52 or 3.54 except a 2 pins that had juice that should have been dead but those were like .34

I'm fearing my inability to identify pin 1 of an SMD 4558 is to blame, but has anybody seen a puff of smoke waft out of their op-amp chip touching the wires to a 9v battery during preparation to use the DMM to check pin voltages? I went with polarity as marked on pcb and battery.
I've tried uploading a pic of the board but it's about as wonky as registering for the forum of who sold the board.... closest I have is a line from side to side that is to the left when you can read the writing normally and it's from texas instru I bought through mouser.
https://www.pedalpcb.com/product/pcb465/ bites even they have no documentation for building it, yet. The line as soldered is towards the mid electrolytic cap/ LED and away from the jack grounds/power wires. Can anybody assist with which way this thing is supposed to go? I think I may have already cooked the chip but I'll just tack a new 1 on to the order for the parts if it is fried when M'bean releases Tourbus

Late edit, anybody have an idea which end was pin 1?
<a href="https://www.imagevenue.com/ME14WUTG" target="_blank"><img src="https://cdn-thumbs.imagevenue.com/a6/bc/bc/ME14WUTG_t.png" alt="SMD 1pjt.png"/></a><a href="https://www.imagevenue.com/ME14WUTH" target="_blank"><img src="https://cdn-thumbs.imagevenue.com/85/f9/60/ME14WUTH_t.jpg" alt="SMpjt.jpg"/></a>my apologies IF the thumbs aren't showing.