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Aquaboy help needed

Started by krankor, December 30, 2012, 10:41:43 PM

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krankor

hope somebody can help me with this. i've spent a lot of time on my own and could use a fresh set of eyes. built an aquaboy that won't make a sound. it's the 2012 edition. made my own board. used a 3205. here are my voltages:
9V=8.37
VB=4.18
VD=4.6
   
Q's (E,B,C):
Q1: 3.1,3.9,8.37
Q2: 2.4,2.9.8.37
Q3: 0.6,1.1,8.37
Q4: 200mV,200mV,8.37

IC1 353;
1: 7.6
2: 2.6mV
3: 4.2
4:1.5mV
5:4.19
6:4.52
7:1.4V
8:8.37

IC2 570
1:0.9
2:1.8
3:1.8
4:3mV
5:1.8
6:1.8
7:4mV
8:1.8
9:1.8
10:3
11: 3
12:1.8
13:8.37
14:1.8
15:1.8
16:0.7


IC3  3205
1:4.6
2:0.9
3:320mV
4:3.9
5:9mV
6:1.4
7:1.1
8:1.1

IC4 3101
1:4.6
2:0.9
3:8mV
4:1.4
5:1.4
6:1.4
7:2.8
8:4

Q3 and Q4 voltages looked potentially suspect to me so I replaced Q4 with no change. checked all my resistors. pots are ok. all the trim pots seem ok except the 10K cancel trimmer doesn't seem to cause a change in voltage anywhere. I replaced it but still no  change. On the schematic, pin 1 of IC3 is labeled as ground but i have a voltage of 4.6V. so either there is a problem there or there is a difference in pinouts between the 3005 and 3205 that wasn't reflected in the schematic.

OK thanks!


Nick