MN3007 ADA Flanger Clone Questions

Started by Paul Marossy, February 19, 2009, 11:37:41 AM

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Tantalum7

Problem solved.  IC3 was in backwards.  All the other ICs face in the opposite direction, and I installed the the socket correctly, but the chip was reversed.  Thanks for the help. 

StephenGiles

Quote from: Tantalum7 on March 11, 2009, 02:27:06 AM
Problem solved.  IC3 was in backwards.  All the other ICs face in the opposite direction, and I installed the the socket correctly, but the chip was reversed.  Thanks for the help. 

Easily done, I reverse wired power to my last LM324 on Sunday - result.........misery!
"I want my meat burned, like St Joan. Bring me pickles and vicious mustards to pierce the tongue like Cardigan's Lancers.".

JoeGuitar

Where is the layout for this if I want to etch a board?   ???

Thanks
Joe

Paul Marossy

Quote from: Tantalum7 on March 11, 2009, 02:27:06 AM
Problem solved.  IC3 was in backwards.  All the other ICs face in the opposite direction, and I installed the the socket correctly, but the chip was reversed.  Thanks for the help. 

Yeah, I might have done the same thing if I hadn't looked at the component layouts on the original ADA schematics so much while repairing and/or tweaking some real ADA Flangers for people! It's the only one on the PCB that's "upside down".

Tantalum7

Having recovered from the reversed IC problem, I find myself with another dilemma.  I can't seem to be able to set the clock frequency correctly.  Before I get too far in, let me make sure I'm not doing something completely stupid.  In reading the clock frequency with my DMM, I connect the black lead to ground on the board and use the red probe to check the freq. at pin 13 of IC6, correct?  Assuming this is the right way, I can't seem to get the TR5 to be able to stabilize on 34.8khz unless I also tweak TR4 a bit.  Then when I go to set the max frequency with TR4 it won't reach 1.3Mhz.  Also, if I try to check the range, the frequency seems to oscillate at both extremes of the range pot.  Has anyone else encountered this?  If these questions seem a bit simplistic it's probably because I've only got a few builds under my belt and nothing quite this complex.

Thanks,

s

Tantalum7

Anyone have any suggestions at all about my clock frequency problems?  Am I even close?

neil411

#106
I had to get a real good ground connection, I found I couldn't get a good reading by just holding the ground probe to ground. I had to use a short connector with alligator clips at both ends to connect the black probe to the ground (that also freed up one hand). I connected to the ground lug on output plug.

There is a test point on the PCB just above IC6 marked "TP". Use that and you will know that you are checking the correct pin on the IC.

I had to use double the frequency as Bajaman suggested.

neil411

JoeGuitar, there is no layout, we all purchased a board from moosapotamus.

Paul Marossy

Quote from: neil411 on March 12, 2009, 03:32:03 PM
JoeGuitar, there is no layout, we all purchased a board from moosapotamus.

Yes, but if you are resourceful, you could make one using this as a guide (I personally wouldn't attempt it, though): http://www.moosapotamus.net/IDEAS/ADAflanger/ADA_MN3007/ADAflangerOVRmn3007.GIF

Don't forget that it is double sided, so you have to run wires for all of those tracks on the component side of the PCB.

Tantalum7

Excellent.  Thanks.  That's what I need to get started tracking down any issues I may have.  I wasn't sure what test point people were referring to before.  It seems that the frequency at the chip is supposed to be half what bajaman suggested for the frequency at the test point according to previous discussion.  I'll see if I can get a constant frequency there.  I was having some issues of the frequency sweeping during one test procedure.  Does it matter whether the flanger is switched on or in bypass when checking the frequency? 

One last stupid question.  What is JK1 for and does this jack have to be connected for the flanger to operate properly?

neil411

#110
RE: JK1 - scratched my head on that one for a while too. That's for using an expression pedal with the Flanger. Requires a stereo jack, and my understanding is that you do not need to connect it for the pedal to work - but don't quote me on that.

I'm still confused  about the frequency numbers. That was not clearly addressed in this thread AFAIC. I couldn't get the 34.8k/1.3m numbers, but I could get the 69.6k and 2.6m, so I went with that.

Maybe someone else could address that issue again and make it more clear for us non electrical engineer types.  :icon_wink:

I thought the Neovibe was a tough build until I built this thing.

Tantalum7

Quote from: neil411 on March 12, 2009, 03:59:11 PM

Maybe someone else could address that issue again and make it more clear for us non electrical engineer types.  :icon_wink:

There was some discussion in this thread before about why the two test point and pin 13 should have different frequencies, but a quick refresher would be greatly appreciated.
Okay, that's what I suspected about JK1, but I didn't really know if it had to be connected or at least jumpered to get a working flanger.

moosapotamus

#112
RE: JK1
Note that the Manual control will not work if you simply do not install a stereo switching type jack, as drawn in the schematic. If you do not want to install a jack, you will need to install a jumper between pad Sw and pad S so that the wiper of the manual pot is connected to R53.

Installing the jack and being able to sweep the flanger however you want with a foot pedal is pretty cool, tho. Check out Mouser PN 502-13B. 8)

~ Charlie
moosapotamus.net
"I tend to like anything that I think sounds good."

Tantalum7

On the schematic it looked like something had to be connected there to get the manual pot working.  I'll jumper it to see if I'm finally able to calibrate it correctly now.  It didn't seem as if the manual pot was doing much.  I think this tells me why.  Thanks for that critical bit of info.

s

Tantalum7

I finally have flanging.  I made all the recommended changes of resistor values and cut the necessary trace, but  it's still difficult to get the max and min frequencies to stabilize.  Even with back and forth tweaking between TR5 and TR4 it seems as if either I can get the 69.6kHz or 2600kHz, but not quite both at the same time--close, but not exact.  Also, TR3 seems to be difficult to set because the frequency is sweeping through it's range.  I'll have to see what happens next week when I can get access to a scope.

Thanks for all the help and patience.

Michael Allen

Quote from: Paul Marossy on March 12, 2009, 03:37:36 PM
Quote from: neil411 on March 12, 2009, 03:32:03 PM
JoeGuitar, there is no layout, we all purchased a board from moosapotamus.

Yes, but if you are resourceful, you could make one using this as a guide (I personally wouldn't attempt it, though): http://www.moosapotamus.net/IDEAS/ADAflanger/ADA_MN3007/ADAflangerOVRmn3007.GIF

Don't forget that it is double sided, so you have to run wires for all of those tracks on the component side of the PCB.

I actually successfully made one of the old ones, and then made a new double sided one. didn't get my top and bottom lined up perfectly so there would have been some trouble areas. Scrapped the whole thing and bought one instead.

So. Who wants to calibrate mine for me? Someone with a scope and frequency counter willing to calibrate mine if I ship it to you? I finished the MN3207 version, 15V regulated supply with 9V for the BBD. Works and sounds freakishly because I don't know what the crap I'm doing with all those dials.

If anyone's willing to do this for me (I"ll ship it to you and back to me) please let me know!

StephenGiles

Veroboard my friend - that presents none of these problems :icon_biggrin:
"I want my meat burned, like St Joan. Bring me pickles and vicious mustards to pierce the tongue like Cardigan's Lancers.".

StephenGiles

Quote from: StephenGiles on March 14, 2009, 07:25:29 AM
Veroboard my friend - that presents none of these problems :icon_biggrin:

Don't mean to sound harsh, but unless you are listening to the ADA through headphones with no other instruments, I don't believe you will hear any difference.
"I want my meat burned, like St Joan. Bring me pickles and vicious mustards to pierce the tongue like Cardigan's Lancers.".

oldschoolanalog

On adjusting the clock:
Quote from: oldschoolanalog on March 04, 2009, 11:19:44 PM
Note bajamans advice to follow the A/DA calibration procedure exactly.
Here: http://moosapotamus.net/IDEAS/ADAflanger/ADAcalibration.jpg
Quote from: bajaman on March 04, 2009, 02:44:55 PM
...To adjust just follow the ADA calibration procedure (moosapotamus site has it i think) EXACTLY but set the speed range to double what they specify. (34.8KHz becomes 69.6KHz at the bootom end and 1300KHz becomes 2600KHz at the top end)
Take note that A/DA says to take this reading at Pin 13 of IC6 (4047); the clock test point (see A/DA rev 3&4 schematics).
This will give you a 2 phase clock of 34.8KHz to 1300KHz at pins 10 & 11 of IC6.
Exactly double the 2 phase clock of 17.4KHz to 650KHz that is specified by A/DA on the Rev 4 schematic.
Note TR4 & TR5 are very interactive. Exercise patience and you'll be OK  ;).
Also realize the "test point" (Pin 13 IC6) may not be a 50% duty cycle making readings potentially difficult (depending on your test equipment).
However, taking the clock f readings at the BBD assures you of a nice buffered clock with (hopefully) a 50% duty cycle.
Your choice...
Mystery lounge. No tables, chairs or waiters here. In fact, we're all quite alone.

neil411

I'm still confused.

What is the clock speed I should get at the test point?