Flintlock Flanger build problems hum

[Spenzerleehorton]

ive taken out all IC's and i put them in one by one and looked at 15v test point and all is good.
IC2 pins are out and i cant see why?
Ive tried adjusting bias but nothing changes apart from getting no sound all the way one way?

Anyone got any pointers please?

[Spenzerleehorton]

I need to look at IC1 sorry!!!

[Spenzerleehorton]

Adjusted bias and IC1 falls in, IC2 is out so need to find what's wrong there?
Getting low voltage on 2.1 and high voltage on 2.2!

[Scruffie]

IC2

1 - 4.8v
2 - 4.8v
3 - 4.8v
4 - 0v
5 - 7.2v
6 - 7.2v
7 - 7.7v
8 - 14.4v

These are right, unless you're saying changing the bias has changed them in which case you must have a short somewhere.

[Spenzerleehorton]

When I take out the 4049 I get 15.06v at test point and when it's in the voltage drops to 14.96v, so could be a problem here?
When I've had hum before it's normally a component drawing too much current and the circuit voltage dropping below where it needs to be, this might be the case here so I e ordered a couple more cd4049 as I need another one for the electric mistress.
It seems I'm not getting an effect signal which could be that the 4049 is down, I'll try and have a look with scope and see where the signal gets too.
Any other ideas?

[Scruffie]

The 4049 is very current hungry so the voltage dropping with it in isn't surprising.

Did you install C37? It seems it causes some problems if it's put in.

Did you check the FET datasheet and resolve the wet signal disappearing?

Does IC1.2s pin 7 voltage vary with the bias trimmer?

Post up some photos so I can give the board a look over.

[Spenzerleehorton]

i've taken out the 4049 and put it in the electric mistress and now that doesn't work!! so i'm thinking the 4049 has gone plop!!
as both pedals did work previously.
Ive put in TL072 instead of the 1458, i also have a few 4558 if needed which i think work for IC4.

[Spenzerleehorton]

other side

[Scruffie]

TL072 is not a suitable replacement for IC4 and 4558 aren't much better, they may work but they also might not, a TL022, TL062, LM358 or the LM1458 you had in there are better choices, you had moving voltages on IC4 so it appears the LFO was working anyway.

Well if the 4049 killed a working pedal then yeah, quite possibly it's dead, they are static sensitive.

You've put the 2N3819 in the wrong pads, it's D,G,S not G,S,D.

You might find all that long wiring for the pots causes issues, might explain the high pitched interference you had.

[Spenzerleehorton]

Ok great stuff, I actually have some more 2n5457 which arrived yesterday so will change and shorten all the wires.
I will also change back the 1458 in IC4.

[Spenzerleehorton]

IC4 now like this with LM1458 in!!
1 - 13.97
2 - 7.1
3 - 14
4 - 0
5 - 7v
6 - 0
7 - 14.98
8 - 14.98

so defo something wrong!!!

[Spenzerleehorton]

replaced IC9 4049 and 4047 no change, this pedal is getting closer to the bin now!!!
electric mistress now works as i've put in the 4049, one down.
getting voltage drop when put in brand new MN3007 so will test this in the electric mistress to make sure works.
Im going to test all voltages again then try and trace with scope!!


also scruffle, i thought IC2 was wrong as pin 1 on your sheet says 9v, but i take that its a misprint and meant to be 3v?

[Scruffie]

I hadn't looked at them but yeah, those voltages are no good. Your IC2 was fine, the only issue you had was half of IC1.

Odd that your IC4 worked and now doesn't...

Again, your IC10 voltages were fine apart from the bias which is fed by the half of IC1 with the wrong voltages.

[Spenzerleehorton]

well i've twiddled and adjusted the c-max and c-range and now have flanging again!!
I've not test frequencies but there is a loud swoop/swoosh which i twiddled out as its was unusable.
Have got it sounding ok apart from a little high pitch chirp in the background?
do i need to put in that other cap C37?

[Spenzerleehorton]

I've also shortened all the wires and tested outside the box.
I'm pretty sure the frequencies are not 69khz to 2.6mhz!!!
Does this matter?