Anybody have a source for MN3009/3209 256 stage BBDs?

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or do you know of an old "consumer electronic" product i can harvest them from? as always, any help is greatly appreciated.
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[Mark Hammer]

There is a pair in the Roland Juno 106, used for the chorus effect.  I've got a busted one, and I've been torn between trying to bring it to life or cannibalizing it for parts for over a year now.

My Washburn SC-7 chorus pedal also came with a M3209.

They're around, here and there, but nowhere near as omnipresent as the 1024-stage devices.

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Thanks Mark! you mentioned in another thread that the R5106 is a 256 stage device. cant seem to find much info on it. you also mentioned it uses a single phase clock .  can you PLEASE elaboriate (just a bit...). you mentioned the pinouts; any additional info would be greatly appreciated. eg: supply voltage, bias requirements,clocking, etc. these chips are readily available from Small Bear (thanx again, Steve!), and might just "fill the bill".
many thanks!
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[Mark Hammer]

Thanks Mark! you mentioned in another thread that the R5106 is a 256 stage device. cant seem to find much info on it. you also mentioned it uses a single phase clock .  can you PLEASE elaboriate (just a bit...).

Bucket brigade chips consist of two metaphorical lineups of people passing buckets of signal.  Now imagine there is one person at the very end of the line who actually throws the water on the fire.  They can't take two buckets at the same time, so here's what happens.  Whenever the person at the end of lineup one is passing a pucket,the person at the end of lineup two is turnign to the side and getting another bucket.  IN other words, whenever the folks in lineup A are turning to their left, the folks in lineup B are turning to their right.  So, there is never a gap in water to be tossed because *somebody* is always busy getting another bucket.

BBDs use two complementary (opposite phase) clock pulses driving two parallel series of stages.  Whenever clock A says "Move your sample down, boys", clock B says "Hold up for a sec", and vice versa. At the output, those two complementary series of stages combine their signals in equal proportion and you end up with a sort of stitched-together copy of the original input signal.  If you look at the datasheets for any of the MN3xxx chips, you'll see there are two outputs, and if you look at any schematic using one of them, you will see either: a) the two pins simply tied together, b) two equal value resistors coming from those two pins, or c) a trimpot for precision matching/mixing.

Okay, so what's the deal with the single clock input?  The MN3101/3102 clock chips normally put out the two complementary (one out of phase with the other) clock pulses that drive each of the two chains of storage cells in the BBD.  That's handy but the MN3101/3102 aren't the greatest chips in the world for overcoming the capacitive loading of those clock input pins on the BBD.  When you use one of them, without any outside help, you essentially trade convenience for the ability to have very high clock rates and short delay times.

What some designs have done instead is used a flip-flop circuit to divide down a master input and produce two complementary clock signals.  You can see an example of that here: http://ampage.org/hammer/files/PAiA_Phlanger.PDF

Note that the clock generator is an NE566 oscillator chip (IC4), and its output from pin 3 goes to the input of the 4013 flip-flop chip (IC3).  That chip, in turn, produces two complementary outputs at pins 1 and 2, which go to the BBD.  The R510x series and the SAD512D included a flip-flop circuit on-board, such that the user/designer would only have to feed the BBD with a single clock signal. All of the dividing down into two opposite clock pulses was done on the BBD itself.

That does two things.  First off, that's one less pin you need to use for something else.  Second, that's one less clock line running around the board to potentially produce audible noise in other parts of the circuit.  Third, because you don't need to run lines to a flip-flop somewhere, the single clock line can be kept really short by snuggling up the clock generator next to the BBD.

make sense?

There is some rudimentary R510x info in the BBDementia zipfile here: http://ampage.org/hammer/files/BBDementia.zip  I need to update that file, though, since people have been kind enough to send me additional datasheet scans.  Info on the SAD512D can be found here: http://www.synthdiy.com/files/1/2003430/SAD512D.pdf

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understood, Mark. i like the idea of only running 1 clock line. simplifies things quite a bit. i'm going to order a few R5106's and get out the old protoboard...  thanks for sharing all this great info; you are truly the "Rosetta Stone" of the DIY set!!!
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PS: you use a juno 160 for parts?  seriously hardcore...

[Mark Hammer]

PS: you use a juno 160 for parts?  seriously hardcore...

I didn't say I had, just that I was pondering it.  Of course the fact that it is even on the table for discussion makes me "hardcore", I guess.   (A lotta terrific chips in there well worth more than the $50 I paid for the beast: MN3009's, MN3101, TL074, and 6, count 'em, six IR3109/BA662 combos).