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Sorry for the delay replying. see what i did there? delay? funny shtuff :^| ...anyway. Probing at the output of the BBD you can hear a mixture of clock signal and input signal. The clock signal is filtered away by the time you get to Q4 and is healthy sounding until it passes through R33 where it sounds heavily attenuated and low pass filtered like it is coming from the apartment next door.

looking at the signal on the scope you see  the clock signals and what i am guessing are discrete voltage samples- square wave and higher amplitude spikes, all positive going. then  at the output of the compandor the square wave clock signals are gone and the spikes are both positive and negative going. after R33 it is hard to distinguish signal from noise.

i checked all the R and C values around IC1B and they are correct.

hehe! yeah sorry i took that terrible pic with my computer camera and it took way too long to even get that good of a shot of it. i wish someone would explain why you get a mirror image and why it would be so hard to correct for. weird. but anyway yeah to look at it you would say it looked pretty legit. and it might be-i made this thing almost a year ago during a real solder binge and i have been known to not think and just blindly plug in the chips without thinking about which way they are supposed to go cuz i am in such a hurry to hear if the thing works.

yes there is a signal at the input of the 3205. unfortunately haha! that`s what makes me think it is either bogus or i ruined it. spensive mistake if that`s what i did.  Thanks for the help!

i did run across this from Brian in another thread :
Okay, try this instead: remove D2 from the PCB and put a jumper in its place. Now put D2 (or another 1n914 or 4148) between pin1 and pin8 of IC4 on the bottom of the PCB as illustrated below in orange. This will set the Clock at the same voltage as the BBD and change the Vgg voltage to about 14/15 of the Vd supply.

If that doesn't work, it may be a bum BBD.

A lot has happened...but still no delay! The 3101 turned out to be fake or i fried it, or both but i forgot i had one lying around from a different seller and hey it worked! nice healthy clock pulses on the scope and here are the new voltages:
IC1 LF353
1:4.5
2:4.5
3:4.5
4:0
5:4.5
6:4.5
7:4.5
8:9

IC2 NE570

1:1
2:1.8
3:1.8
4:0
5:1.8
6:1.8
7:3
8:1.8
9:1.8
10:3
11:3
12:1.8
13:9
14:1.8
15:1.8
16:0.8

IC3 MN3205...now thinking it is fake or fried
1:0
2:4
3:3.7
4:3.7
5:7.9
6:4
7:3.8
8:7.2

IC4 3101
1:7.9
2:4
3:0
4:4
5:4
6:3.9
7:3.9
8:7.2

Q1
E:3.4
B:3.8
C:9

Q2
E:2.1
B:2.9
C:9

Q3
E:6.3
B:6.9
C:9

Q4

E:2.1
B:2.1
C:9

When i look at pins 3 and 4 on the mn3205 on the scope all i see are clock pulses. is the delayed input waveform supposed to be riding on those? they then go through the cancel trimmer and it does its job. then all you see are tiny spikes which i am guessing are artifacts from clock pulses that didnt quite cancel. but no input waveform.

so with the functioning 3101 here are voltages for the 3205 pins with the 3205 removed:

1:0
2:4
3:0
4:0
5:8
6:4
7:3.5
8:7.2

and the 3101 removed (3205 back in)

1:8
2:0
3:0
4:0
5:0
6:0
7:0
8:7.7

couldn`t find the aquaboy 2012 project on this site so i included the pdf and a pic of the mn3205. ok i think that is everything. thanks again!

cool thanks for the replies. The chips are from chinese sellers on ebay:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=150720096426&ssPageName=ADME:L:OU:US:3160

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=180476363561&ssPageName=ADME:L:OU:US:3160

i bought both of these chips about a year ago and the dealers still have stores on ebay so at least that is mildly encouraging. sort of.

oh wait i also bought some 3007s and 3101s from somewhere else at one point and i know the 3007s work. well it has been a while..not sure. will try to get some pics up tomorrow.

also should have mentioned that i etch my own boards, so, you know..

hope you solved the problem. maybe you could help me though and take a quick look at my voltages. just posted this http://www.madbeanpedals.com/forum/index.php?topic=12718.0
mine has no delay at all..

sorry meant aquaboy *2012*

hi,

using a mn3205 (checked the jumpers already!) here are my voltages:

IC1 LF353
1:4.5
2:4.5
3:4.5
4:0
5:4.5
6:4.5
7:4.5
8:9

IC2 NE570

1:1
2:1.8
3:1.8
4:0
5:1.8
6:1.8
7:3
8:1.8
9:1.8
10:3
11:3
12:1.8
13:9
14:1.8
15:1.8
16:0.8

IC3 MN3205..COULD IT BE FAKE?

1:0
2:1.5
3:0.28
4:0.3
5:5.6
6:0.9
7:2.7
8:4.9

IC4 3101
1:5.6
2:0.9
3:0
4:1.5
5:1.5
6:1.5
7:3.8
8:4.9

Q1
E:3.4
B:3.8
C:9

Q2
E:2.1
B:2.9
C:9

Q3
E:.005
B:0.288
C:9

Q4

E:0.005
B:0.005
C:9

probe shows that the signal gets very low at the junction of C35 and R35. should the voltage coming out of pins 3 and 4 on the 3205 really be on the order of tenths of a volt? I would say that maybe the voltages for Q3 and Q4 looked funny if it werent for the fact that the output of the 3205 seemed so low.

any help appreciated!

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

Oh...hehe...yarp. Little things. I need stronger glasses.

Wondered whether the type of LED  I was using might be an issue but I breadboarded the circuit and it works fine. So I guess it's probably an issue with my board or my soldering or both

Hi, hope it's not a no-no to post about non madbean pedals. I built this pedal:

http://www.runoffgroove.com/phozer.html
fabbed my own board:

http://www.runoffgroove.com/phozer2-pcb.pdf

I'm getting a signal and the filter section of the pedal is working. I used LED's and LDR's instead of the vactrol sited in the parts but in their description they say they did this originally as well.

The problem is I can't get the LFO section to work right. +ve input of U1a is around 4V and my scope confirms that U1a is oscillating and that the signal is making it to the +ve input of U1b, but the output of U1b is a flat 6V and the LEDs just glow at a constant brightness.

Anyone have any thoughts on this?

Thanks!

Good advice thanks had already done that cuz I've learned the hard way hehe. But it turned out that changing the bias on Q1 helped alot. Thanks for all the help!

Cool, will try it. Gee, I actually learned something!

Thanks for the reply! Tried going down to 6.8k on R4 and the voltage on the collector of Q1 is now about 7V, but I haven't noticed much change in the gating. hmm. would you be able to point me to a link that has some discussion of how this effect works?

looks like there are a few more amplifier stages where i might try lowering the resistance on the Q collector?

Thanks for the help!

Hi! This is my first post to this forum.

I just finished making the poindexter pedal and it's working except that the signal is overly gated. The guitar volume has to be all the way up and if you back of even a little the signal just gets gated. I used 1n34a diodes and 2n4401's for the transistors. Really hoping  no one's gonna say that the 4401's are the problem hehe!

I checked all the resistor values and they are correct. I did substitute a 47pf cap for the 10pf cap cuz that's what i had. so i put 2 18pf caps in series and swapped them and it didn't seem to make a difference.  Any thoughts would be appreciated!