SOLVED Low tide mini... is it possible to fry a Mn3207??...

[LukeFRC]

So I built a Low tide mini and a Chop shop... neither worked first time... but it's my first time using SMD components so it must be that right?

The chop shop it turned out to be the 2N2222 that needed replacing and it works...

The low tide mini is a bit more daunting to look at...
So first things, before I waste anyone's time with pictures... is there a order you would test things?

Going by the schematic here https://docs.pedalpcb.com/project/LowTide-Schematic-PedalPCB.pdf with an audio probe I've got Signal coming out of Q2 fine and Q1 and Q2 seem to be doing what they should .... I would have thought I could got the mix control to dry and get signal to the mix and level pots but it doesn't look like it :S

 

[LukeFRC]

Oooh I’ve got signal through it on both sides of the mix control - this is promising

 

[LukeFRC]

Right so…

Non effected signal working fine

Gate filter works when tuned all way up, inside control can set it to the range that seems to kinda work …and is like a crazy envelop filter… turn it anti clockwise and no signal…

So think nothing getting through the modulated channel …

Question -if I had stuck the MN3207 upside down to begin with … have I killed it?

 

[LukeFRC]

Because photos are important… I took out the BBD chip and then bridged sockets 3 and 7 - and seem to have the lpg working, it’s got the fretless thing going on that you hear about.

Next I guess is to check that the randomiser and cd4046 bit of the circuit is working and then try and find a new mn3207/v3207d

I’ve not found anything online that definitively says if you put this in upside down it fries it - but I presume it would

 

[giovanni]

I don’t think you could have fried the IC that way. The data sheet shows that this chip can be used with Vcc at pin 1 or 5: this is unusual to me but maybe the BBD has some sort of internal symmetry. But in short, if that’s the case it means that if you mount it upside down it won’t get destroyed. Did it get very hot? Did it produce smoke?

 

[LukeFRC]

I don't know! It's on the bottom level so it was only after initial testing with no signal that I opened it up and noticed that it was upside down

 

[Locrian99]

I fried an mn3207 on a breadboard once by accidentally connecting I think it was pin 7 to both ground and +9v I had magic smoke

 

[LukeFRC]

Hm so I’ll have put 9v or just under through pin 8 and ground … so yeah most likely it’s that fried

I’ll check and test the rest of the circuit first - 3207 are not easy to get in the U.K. at the moment. Buying an old behringer chorus would almost be easier and cheaper!

With the chip bridged I was getting the lpg working kinda right but I think out of phase with the dry signal
The randomiser seems to be working too - I just need to check the cd4046 bit next

 

[LukeFRC]

So it’s working!

Yes in looks like you can fry a mn3207 - a replacement and it worked first time

A beautiful sounding deceptively subtle pedal - I like