SMD screamer

Deperduci

Well-known member
So I've tried building this https://www.pedalpcb.com/product/pcb465/ and had immensely shitacular luck so far. 1st board, something happened at Mouser's website I get 75% parts as size 201 instead of 805. get new batch of parts put the opamp on backwards, not much info which end was pin 1 for the make I used >< smoked the chip, try to be cheap saving parts, I pull the traces off the board, but think that was from while trying to clean the flux I accidentally grabbed the acetone instead of iso for 2 swabbings... may have dissolved the lamination glue. Get new board, couple times I've found an end cap missing off a component...
Now I can't get sound with effect o. it appears I have all connections made/soldered. Works fine in bypass triple checked tip vs sleeve for the jack wiring, led lights up, no beuna. I'll add in pics after I've had a semi decent nap. Dear proprietor is the build document ever coming out? should I just write the whole fiasco off as lessons in smd soldering?
 
Just use the original TS808 schematic and the shop pcb image where you can see most of the traces those pads with the faint crosshair type thing go to ground

You should be able to work out where the vias connect from the original schematic

A wee bit extra work but that's what I do awaiting the build doc not being the most patient guy on the planet

SMDScreamMachine.jpg
 
I attached the board to the pedal through a section of pin header. It made a 4 point/2 ends attachment to the the box for stability. I'm about to make another round of chip inspection just using the resistor section of my DMM. This last time, it SEEMED like nothing was refusing to accept solder. the power wires look like crap but I can swap that out for a longer strand or 2, I chose that setp because it was an internal nut, I'm low on externals, saving for stuff like Memory Man clones and such that need to be thoroughly volt checked prior to install.
 

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The photo isn't clear. I am a bit sus of the soldering on the transistors, but it is hard to tell. What voltages are you getting on the IC?
 
I can't hold the ipad straight enough anymore and it's the highest resolution I have, no regular camera and the phone is impossible to get off this stupid auto-focus crap that zooms in on the box sides >< all pins nada, zilch bopkiss. pos side of power jack and signal input side of diode below the power coupling and led positive leg are 9.37. 0.00 any and everywhere else.
 
That would do it. 1 way 'valve' pointing back at the supply.... 🤬 I'll get that flipped around, was escaping my attention, again, from my looking for missing end caps more than polarity. I've had such a bad time with TS boxes even though I've only bothered building 2, this and the multi choice box from aionfx... that 1 is occasionally scratchy or just an extra volume knob.
 
Got the diode swapped, still no sound.
pin voltages 1:7.94
2: 7.39
3: .79
4: 0
5: 7.93
6: 7.94
7: 0
8: 0
So I'm now at where is the voltage loss for pin 7 or 8. other builds with 4558's I know 4 is either dead or a ground. This is going better than my Collosalus. I'm glad my last p-up arrived, think my days off for awhile I'm going to work on my ric copies instead.
 
May have it this time, I did a pull test using tweezers and the iron instead of the magnifying glass. 3 resistors popped off, both 510k's and the 1k going to the 3 leg of the b100k pot. That'll likely explain pin7. now to shop for replacements... last money I'm spending on this 1 at the point I could have bought an assembled off reverb with all the shipping charges ><
 
Just a newbie question. Those SMDs are so tiny that me thinks that they are easily over heated. What soldering iron is recommened? Maybe a needle tip?
My soldering skills are not too bad, but i think i stick with fullsized parts.
 
Just a newbie question. Those SMDs are so tiny that me thinks that they are easily over heated. What soldering iron is recommened? Maybe a needle tip?
My soldering skills are not too bad, but i think i stick with fullsized parts.
You should be using lower temp solder for smd…~450F
 
May have it this time, I did a pull test using tweezers and the iron instead of the magnifying glass. 3 resistors popped off, both 510k's and the 1k going to the 3 leg of the b100k pot. That'll likely explain pin7. now to shop for replacements... last money I'm spending on this 1 at the point I could have bought an assembled off reverb with all the shipping charges ><
Would you like me to send you a complete component kit for this? I have a few made up after I built it, and never did a giveaway for them. :(
 
That's very kind of you Fig but all the other bits remained in place. I have an aionfx I built as a TS-9 and I got this 1 to mostly learn/practice smd work. I'd have more interest in an Electric Ladyland board Or a good source for decently priced power transformers I'm still window shopping at digikey and mouser looking for something has a 18~25vac output, Vigilante's 1 source looks to be for octavia style pedals(and a good 1).

As for temp/iron a 30 to 60 watt iron is fine, especially if you can find 1 with a voltage/temp rheostat on it. Using the lower temp stuff, possibly the paste solder so you have less contact time will help prevent the part/pcb blowouts I've had along with making sure you use IPA instead of acetone to clean the flux off when done...🤦‍♂️

Post shopping edit, I's a twit.. it's 3k7's are diff from 3207s. I might order a pair of mn3207/3102's, 1 for Cephied and other put away for a chance at that board developed.. board ;)
 
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I'm giving up on this 1, resistors arrived from Digi-key... not sure how their software screwed it up but instead of the 1k I received a2,2m and then when I tried to put the 510's on 1 hit the floor and headed to Cuba.. or somewheres Caribbean. I'm tossing this in a cardboard box for minimum 2 months then might booger in a couple through holes just clearing the lid... me+Ts boxes =/= a working situation. Rob makes designs great boards but only so much shitzapoolooza I can take on a project, especially when it's holding up a backload of other stuff I could have bought parts for. I'm cursing my own luck on this only.
 
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