Deathklaw Delay Breadboard Debug

Started by rthryhorysak, November 28, 2015, 12:55:27 PM

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rthryhorysak

I breadboarded the new Madbean Deathklaw circuit, and basically there is not delay, just the buffer is outputting signal. Here are my voltages. I have gone through everything and checked that the connections were right. The first PT2399 is clearly a problem. so if someone could help me out that would be appreciated.
http://www.madbeanpedals.com/projects/Deathklaw/Deathklaw.pdf

IC1 – TL072
1 - 4.32V
2 - 4.32V
3 - 4.32V
4 - 14.8mV
5 - 4.32V
6 - 4.32V
7 - 4.32V
8 - 69V

REG
In – 8.62V
Gnd – 10mV
Out – 5.01V

Q1/2 – 2n3904
E – 2.5V
B - 0.63V
C – 57mV

IC2 – PT2399
1 – 5.01V
2 – 2.5V
3 – 16.5mV
4 – 16.3mV
5 – 3.68V
6 – 2.5V
7 – 4.63V
8 - 0.69V
9 – 2.5V
10 – 2.5V
11 – 4.5V
12 - 0.7V
13 – 1.7V
14 – 4.79V
15 – 2.5V
16 – 2.5V

IC3 – PT2399
1 – 5.01V
2 – 2.5V
3 – 16mV
4 – 16mV
5 – 3.68V
6 – 2.5V
7 - 0.83V
8 – 0.84V
9 – 2.5V
10 – 2.5V
11 – 2.5V
12 – 2.5V
13 – 2.5V
14 – 2.5V
15 – 2.5V
16 – 2.5V

PRR

#1
To reduce tennis-neck, I have pasted MB's numbers next to yours.

IC2 – PT2399
----Meas. -- MadB
1 – 5.01V    4.98
2 – 2.5V     2.51
3 – 16.5mV   2.2mV  ??
4 – 16.3mV   2mV    ??
5 – 3.68V    2.9    ??
6 – 2.5V     2.49
7 – 4.63V    0.71   ??
8 - 0.69V    0.82   ?
9 – 2.5V     2.5    ?
10 – 2.5V     2.51
11 – 4.5V     2.51    ??
12 - 0.7V     2.59    ??
13 – 1.7V     2.5     ?
14 – 4.79V    2.45    ?
15 – 2.5V     2.53
16 – 2.5V     2.51

A whole lot of things are not 2.5V, but 0.7V to 4.5V.

I do not know the PT chip well enough to begin to guess.

The "69V" on IC1 pin 8 seems unlikely. We would expect to find 8.82V and zero V on its power pins 8 and 4.

Q1 *and* Q2 voltages don't make sense? (Probably an E/C confusion: Q1 C connects to IC2 pin 6, so expect 2.5V--- ah, I see the same "error" on MB's chart.)
  • SUPPORTER

PRR

Pin 7 is wrong. All else is doing as expected for a wrong pin 7 voltage.

  • SUPPORTER

rthryhorysak

#3
Quote from: PRR on November 28, 2015, 01:45:36 PM
Pin 7 is wrong. All else is doing as expected for a wrong pin 7 voltage.



Ok, thank you. Do you know what would cause this? I keep going through the connections and I can't find anything wrong. Oh and pin 8 was supposed to be 8.69V

PRR

  • SUPPORTER

rthryhorysak

I think it is my PT2399. I switched the two pt2399s and I get some delay. The control aren't working exactly correct, but I think if I replace the ICs then I should be good. Thanks!