Hello Friends!!!
I'm new here. My name is Alberto. I'm from Argentina. Just registered but I'm a follower of this site since several months. :)
This time I need your help with a Dynacomp that I'm building from this Layout/Schematic: http://www.tonepad.com/getFile.asp?id=9
So issue is that the effect sounds with a kind of fuzzy distortion. Level knob works ok but sustain seems to do nothing.
These are my voltages:
C B E
Q1 9.53 2.28 1.82
Q2 7.08 2.97 2.46
Q3 0.64 0 0
Q4 0.64 0 0
Q5 9.53 0.64 0.63
IC1 = CA3080E
Pin 2 = 4.6V
Pin 3 = 4.6V
Pin 4 = 0V
Pin 5 = 0.63V
Pin 6 = 2.6V
Pin 7 = 9.5V
I'll really appreciate your help guys!!!
Thanks!
(http://i1290.photobucket.com/albums/b521/Albert_Martin/ad28e7d9-76a6-4240-81de-391d939d75ab_zps3f07080c.jpg)
(http://i1290.photobucket.com/albums/b521/Albert_Martin/b4e61bf8-803f-4672-b8f5-763bd764a267_zpsefdd5196.jpg)
from a quick look i see an incomplete solder joint toward the bottom right hand side. doubt that will be related to creating a distorted sound, but you should fix that up anyway to avoid any other problems :-)
Quote from: Hav on September 10, 2014, 11:39:45 AM
from a quick look i see an incomplete solder joint toward the bottom right hand side. doubt that will be related to creating a distorted sound, but you should fix that up anyway to avoid any other problems :-)
Yes I noticed that after uploading the picture. Already corrected. Thanks! :)
So far I tried:
- Changing the 150K resistor that links 9V with collector from Q3 and Q4.
- Replacing the CA3080.
- Changed the sustain pot.
And... still same issue. :(
SOLVED!!! :icon_biggrin:
I had a bad joint in the area of the pin 5 in the IC. I realized that because I took off the IC and Q5 but still having voltage in pin 5. That was not possible since Q5 emitter sends voltage to that pin.
Quote from: neo79x on September 11, 2014, 09:23:18 AM
SOLVED!!! :icon_biggrin:
I had a bad joint in the area of the pin 5 in the IC. I realized that because I took off the IC and Q5 but still having voltage in pin 5. That was not possible since Q5 emitter sends voltage to that pin.
Thanks for the link anyway! I've had a DynaComp for probably about 40 years now, and liked it so much I built it right into one of my guitars. Always wanted another, and now I can build me one! :-)