CE-2 debug help and ebay MN3007

[alparent]

I'm building a CE-2 using Tonepad layout. All the components are as specified.

This build also serves as a test for MN3007 & MN3010 I got from ebay.

So far, all I get is basically the clean signal. How can I check if the MN3007 & MN3010 are doing what they are suppose to?
I have a scope if there is something I can test with that?

Might be that the MN's are crap but would like to confirm before complaining to the seller.

Thanks

[armdnrdy]

Alain,

I thought you work with Mark Hammer. I would stroll into his office and ask him to help!

But in case he took the day off....I'll see if I can help out.

MN3007:
First check for proper power voltage on pins 1 and 5.

Oscilloscope or meter. Check for clock signal at clock pins 2 and 6

If you have an audio probe (see Geofex) or an oscilloscope, insert a signal into the input of the effect. Check for the signal at the BBDs input. (pin 3)

If you had a signal at pin 3 check for a signal at the BBDs outputs ( pins 7 and 8 )

MN3010:
Check the data sheet for the pinout. You'll be able to insert the top half of the MN3010 into the 8 pin MN3007 socket to test half  of the dual BBD.

I know I'm no Mark hammer......but I tried my best!  

I'm working on a BBD tester to tell if A. The BBD is good. and B. That it's the proper amount of stages. (Due to counterfeiting)
I've bread boarded sections and so far so good! But I keep getting pulled away to other projects!

[armdnrdy]

I just took a gander at the Tonepad layout of the CE-2.

Alain,
Did you mean MN3101 instead of MN3010?

If you meant 3101 look at the data sheet and check voltages, and signal at the clock pins as above.

[alparent]

Thanks for the help Larry.
I will check the voltages out.

You can be sure I've already bugged Mark about this.
As a matter of fact I'm actually using a mostly populated board he gave me.

Don't worry about not being Mark. None of us are!
But I stile like to make new friends!

Thanks again. Will report on my findings.

[alparent]

OK checked my MN 3007 voltages.

I get almost 9v at pin1
0V at pin5

Input signal at pin 3 but nothing at pin 7-8.

I have clock signal at MN3101.

[armdnrdy]

Hi Alain,

If you input a signal into the effect and you have signal at pin 3 (input of the BBD) and the clock is working you should have a signal at the output of the BBD. (pins 7 & 8 )

You did adjust VR3 (bias trimmer) correct? There should be a relatively small area of adjustment which will result in a "wet" signal.

Check the pull up resistor (R14) for 9 volts on one side and continuity to pins 7 & 8 (output) of the BBD.

If it's none of the above......the BBD is dead!  

[Mark Hammer]

I dropped by Alain's office and chatted with him about it.  From what I could gather, he did follow instructions about setting the bias, and the best he was able to get was a small range where the delay signal was present, but very low level, and distorted.  We went through the schematic and I pointed to a variety of critical locations and asked "Did you get signal here...and here", so we're fairly certain it's not the audio path.  We don't have verfication at the moment that the LFO is working fine and driving the 3101 appropriately.  That remains to be confirmed.

I'm bringing in my Zombie on Monday for him to swap chips with.  If he pops his 3007 in the Zombie socket, and he doesn't hear any walking dead, then we'll know it's a bad chip.