Hello Everyone,
Sorry that I'm asking for help again!
Yesterday I finished this Ibanez NoiseBuster pedal to tame some of the noises coming out of my Pod HD500X.
The sound going in and out the pedal is the same bypassed & on. I have the impression nothing happens when I turn on the pedal.
Components bought at Tayda
I tried different LM1894 chips (see pictures in imgur album) but did not have any spare 4558 around.
Album to pictures: https://imgur.com/a/JLp6V
explanation on how I counted the pins http://imgur.com/DRlZttI
Original Schematic: http://www.dirk-hendrik.com/temp/ibanez_nb10.pdf
Veroboard Schematic: http://tagboardeffects.blogspot.nl/2015/12/ibanez-nb-10-noise-buster.html
Voltages:
DC in: 9.02v (Battery)
Board in : 9.00v
LM1894
1: 0.0v
2: 0.75v
3: 3.45v
4: 4.44v
5: 4.39v
6: 4.40v
7: 8,97v
8: 3.83v
9: 1.30v
10: 3.55v
11: 4.40v
12: 4.40v
13: 4.39v
14: 4.40v
4558 A
1: 0.00v
2: 4.25v
3: 4.45v
4: 4.45v
5: 4.45v
6: 4.45v
7: 4.45v
8: 8.86v
4558 B
1: 0.00v
2: 4.40v
3: 4.40v
4: 4.40v
5: 4.40v
6: 4.40v
7: 4.40v
8: 8.86v
1n4001
K: 8,81v
I guess your 1894 is now dead...
Power supply is @ pin 1 and GND is @ pin 7...
we always count pins anticlockwise from the pip/divot/ding/marker.
(http://www.rbdinstruments.com/blog/wp-content/uploads/2015/01/how-to-count-pins-on-an-IC.jpg)
Re-Orderd the pins Sorry for the confusion
LM1894
1: 3.83v
2: 8,97v
3: 4.40v
4: 4.39v
5: 4.44v
6: 3.45v
7: 0.75v
8: 0.0v
9: 1.30v
10: 3.55v
11: 4.40v
12: 4.40v
13: 4.39v
14: 4.40v
4558 A
1: 4.45v
2: 4.45v
3: 4.25v
4: 0.00v
5: 4.45v
6: 4.45v
7: 4.45v
8: 8.86v
4558 B
1: 4.40v
2: 4.40v
3: 4.40v
4: 0.00v
5: 4.40v
6: 4.40v
7: 4.40v
8: 8.86v
1n4001
K: 8,81v
well your opamps look about right, but that circuit diagram says LM1894 pin 1 should be Vcc, and pin 7 should be ground (0V75 is not ground). all the other pins are mysteries, their correct voltages are not apparent from the schem, they are all AC coupled.
can you power off, remove the ICs from the sockets, then power-up and measure the voltages on the socket pins, please?
Thank you for the replies! When I get home i'll do that at once :)
Board in 9.2v
4558 Left
1: 0.0v
2: 0.0v
3: 4.4v
4: 0.0v
8: 9.2v
7: 0.0v
6: 0.0v
5: 4.6v
4558 Right
1: 0.0v
2: 0.0v
3: 4.4v
4: 0.0v
8: 9.2v
7: 0.0v
6: 0.0v
5: 4.6v
LM1894
1: 9.2v
2: 0.0v
3: 0.0v
4: 0.0v
5: 0.0v
6: 0.0v
7: 0.0v
14: 0.0
13: 0.0
12: 0.0
11: ???
10: ???
9: ???
8: ???
there is a constantly voltage drop between pin 11 and 8. Some of the caps in the lower left and right area also have voltage drops.
Could these 2 be the problem? (the green caps)
https://imgur.com/a/wSZvd
They are supposed to be non-polarized caps in the veroboard schematic so I don't know if their orrientation is correct.
those two green caps are called "geencaps", they are non-polarised polyester film something or other, possibly the most used caps in the world. they are less likely to be the problem than all those other box-caps (also polyester, but box shaped and standard sizes) you have sitting in sockets. we would generally solder caps in, because we'd already had the circuit on the breadboard, and knew what values we wanted in. or we'd follow the BOM.
the voltages on your IC's looks ok, so we need to find something else to blame. I see the Dirk Hendirks schem has fet bypassing, does yours use them or true bypass (I can't see the schem at the layout site - new browser, no plugins). and do you have an audio probe?
I use True-Bypass wiring for all my pedals.
http://www.madbeanpedals.com/tutorials/downloads/StandardWiring_MBP.pdf
I do not have an Audio Probe how should I go about and make or order one?
no buy, first you "search" then you "build" your own audio probe. it is very easy. then you could plug in your opamps, and trace signal thru them. if they check out ok, put the LM1894 back in, trace thru that.
Quote from: requiem1991 on March 11, 2017, 10:27:38 AM
I do not have an Audio Probe how should I go about and make or order one?
You have 10 audio probes, 5 in each hand :icon_wink: