Clean output from Aquaboy

[chromesphere]

Hey chaps,

Putting together an Aquaboy from the extra projects (madbean) section and im having an issue.  Im only getting clean output.  Heres a few observations that might help you....help me

- Get a high pitched squeling on pin 2 and 6 of the bbd (i think thats good yeah?)
- Adjusting clock trimmer changes the frequency of the squel on pin 2 and 6 until it gets so high you cant hear it (again, i think thats working correctly?)
- Get a distorted guitar signal on pin 7 of the bbd.  Turning the bias trimpot acts like a volume control
- None of the dials do anything
- Nothing but clean on the output.  Its a perfect clean signal
- Here are some voltages from the bbd and the clock:

v3205 (coolaudio)
1 0v
2 4v
3 3.4v
4 3.4v
5 7.99v
6 4v
7 0.68v
8 7.3v

Clock (mn3101)
1 8v
2 4v
3 0v
4 4v
5 3.8v
6 4v
7 4v
8 7.3v

EDIT: i've got a strong feeling that the bbd is not output the delayed signal.  with an audio probe i get clean signal on pins 2 3 and 7 on the compandor, but nothing from any of the other pins (ie, nothing from the delay signal!).  I have no idea why though...Everything seems in order, up till it hits the bbd.

Any help is greatly appreciated!
Thanks,
Paul

[madbean]

Here's a checklist.

Have you set the jumpers correctly?
Have you audio probed pins 3 and 4 of the BBD and confirmed there is no delayed signal from the BBD no matter where the BIAS pot is set (the two pins on the upper right of the BBD)?
Have you used the correct value trimpots for Clock and Bias?

[chromesphere]

The answer to those questions is yep, yep and yep!  The bias trimmer is a 20k (couldnt get 22k).  Ive been audio probing most of the ic's, i get no delay signal anywwhere...

The compander is an NE570N, it has an "S" or a "5" symbol on it.  Not sure if that matters.  I dont think it does.  I've seen others use NE570N's in the aquaboy...

This ones stumped me...

Edit: I checked the middle leg of the bias trimmer and it swings from about 7.63v to 0v so i guess its working correctly.

Paul

[chromesphere]

Here are some more voltages hopefully someone can spot something wrong here.  These voltages look awefully repeatitive :|

LF353
1 4.4v
2 4.4v
3 4.4v
4 0v
5 4.4v
6 4.4v
7 4.4v
8 8.8v

NE570N
1 1v
2 1.8v
3 1.8v
4 0v
5 1.8v
6 1.8v
7 3v
8 1.8v
9 1.8v
10 3v
11 3v
12 1.8v
13 8.8v
14 1.8v
15 18v
16 0.8v

Edit: Yep, the bbd's are not passing the delayed signal.  If i audio probe q3 or q4 i get no signal, they are both silent. 

Unfortunately the reason why is beyond my knowledge.

Thanks again,
Paul

[apollo]

You say you're using a mn3101? Should that be a 3102?

[chromesphere]

Build doc says you can use either
Paul

[stecykmi]

Build doc says you can use either
Paul

i believe he's right, you'll need the v3102. you can use either, but they must be matched with the correct bbd chip.

[chromesphere]

Really!?  Wow, thats not how i interrupted the build doc.  Thanks for pointing that out!

So just to be clear, does it need to be a v3102 or can it be either a v3102 or mn3102?  There are plenty of mn3102's on ebay, v3102 are a different story.

Thanks for your help!
Paul

[apollo]

Both will work, use the mn or v 3102 with the v3205. 

[RobA]

I think you can use a BL3102 as well.

Smallbear has the V3102 for $2.75.

[chromesphere]

Small bear shipping to oz unfortunately makes his store pretty not an even option for me...which sucks, but anyway, they are on fakebay for $2 bucks shipped (the mn3102 that is).

I misinterrupted this line from the build doc:

"MN3101 is recommended for IC4 in all versions, but you can use the
v3102 or MN3102 if you are building the v3205/MN3205 BBD version."

I thought it meant, you know, the mn3101 will work with ALL versions (inc the v3205), but the v/mn3102's are 'optional'.  Clearly not what it means though i can see that now.

Thanks for pointing this out!  So great when its an easy fix like this

Cheers!
Paul

[madbean]

You can use the MN3101 with the v3205. You do need to use the 1n914 diode on the board to approximate the correct Vgg voltage on pin (not needed with the v3102). Your vgg voltage is a little on the low side but it should be close enough to make the bbd operate correctly. So, whether the problem resides in the clock or the bbd you are using, I don,t know. It would not hurt to have an Mn3102 or v3102 on hand to test.

[chromesphere]

Thats what i suspected.... (either works).  dam it.

I have the mn3102 on its way, ill test that.  No idea why this ones not working.

Edit: Forgot to mention im using a 1MC pot for delay, i figured that wouldnt make much difference but i thought the aquaboy used an A not a B taper...So i will probably have to have the pot on about 4/5th rotation for a similar resistance.  I will also try and be more precise with my trimpot turning, ive heard there is a very specific spot where the delay will turn on. I havent been listening carefull when adjusting the trimmer, and these Tayda trimmers are so clunky...Anyway, ill try again tonight,

Thanks again,
Paul

[jimilee]

Have you also checked for solder bridges? All the basic stuff?

[chromesphere]

Jimilee, Im the solder bridge checking lord

Well, i got it working!  And theres nothing more i cant stand then a tech help thread without an explanation to fixing it so here goes.

First problem, the delay pot is a log C.  So instead of half way i put it on about 3/4 but i dont think this was the real problem. 

Audio probing pin 7 is a waste of time (in my situation it is anyway).  All i get is clean guitar, which i thought, it should be?  Its the input?  So instead i set the clock trimmer to just out of audible frequency, incase your new to the foray, to do this, audio probe pins 2 and 6 and turn the clock till you cant hear it.  Now, while strumming your gutiar, audio probe pin 3 (the output), you will probably hear nothing coming through, but turn the bias until you can hear the bbd sort of, start up. Thats right mr optopus, you will have fun doing all 3 of these things at once.   Once you hear your guitar signal you will have output.

Oh yeah and as Brian confirmed (and i suspected) you can use the mn3101 with the v3205. 

Now to start on the mods! (double delay / modulation).

Thanks for everyones help! 

Paul