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|12/29/1998 12:54 AM|
||Re: Panasonic BBD Spec sheets|
Thank's for your reply. I was just the short-form data i was looking for, the chip itself is un-obtainable. Maybe Roland is selling it as sparepart.
I know that digi-key still have the data book you mention, but I am looking for at distributor here i Denmark, where I can get it.
Thank's again, and happy new year.
|1/2/1999 9:33 PM|
Happy New Year to you too ! Here is a New Year's present to you and all the other delay experimenters.
Holtek has a digital delay chip good for 200mS of delay.Take a look at here for more information and a .PDF file:
In the Tech America catalog, the HL8955-A goes for about $5 apiece. They look like they'd be fun to experiment with.
|Book Of The Day||
The Ultimate Tone, Volume III by Kevin O'Connor
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|12/30/1998 2:47 PM|
||Making choices in the MN3xxx series|
I've been perusing the Panasonic literature on the MN300x, 320x, and 330x series, and note the following.
1) The lower the operating voltage (330x < 320x < 300x) the faster the chip can clock. So, the low-voltage 3307 can safely clock up to 500khz (around 1msec delay), whereas the 3007 can only safely clock up to 100khz (around 5msec), even though both are ostensibly the same kind of 1024-stage BBD and have the same pinout. Maximum clock rate is obviously not an issue if your concern is getting longer delays (as with the MN3005), but best quality jet-plane flanging requires a chip that can produce delays as short as 0.5msec to produce delay sweeps of at least 20:1.
2) The MN300x series works off a -16v, NOT +16. The lower power versions (MN320x and 330x) operate off positive voltage, making design a little easier to think your way around.
3) The MN330x series work work nicely with 5v regulated from a 9V battery. The MN320x series wants the full 9v.
4) The lower the operating voltage, the worse the noise specs. E.g., the MN3007 is spec'd at 80db s/n, whereas the MN3207 is spec'd at 73db S/N, and the MN3307 at 69db S/N, under the same operating conditions. You also get better headroom and distortion specs from the higher voltage versions.
Putting all this together, the MN320x series seems like the best compromise solution for many purposes, in terms of getting the best noise and headroom characteristics with the fewest design constraints. If fast clocking is your thing, go for the MN330x series. If you want most headroom and least noise under any conditions, and don't mind designing around it, go for the MN300x series.
Even though the 320x versions of many chips are pin-for-pin identical to their 300x cousins, please note that the operating voltages ARE THE OPPOSITE POLARITY. DO NOT STICK A 3207 IN THE SOCKET OF A 3007 AND EXPECT IT TO WORK VERY LONG OR VERY WELL.
Seems to me that, for a 1024-stage BBD, the Reticon chip could clock much faster than the Matsushita equivalent. Anyone know about this? Are there any legendary flangers that take advantage of this feature? I know the PAiA Hyperflange could sweep down to well less than 0.5msec and used the SAD-1024.
|12/31/1998 8:34 AM|
I can't get enough of this stuff. Thats a rally of good points.
I was contemplating the assembling of the Electro Harmonix Deluxe Memory Man. It is designed around two MN3005's. The voltage on the chip is -15v. Check it out @ Http://www.fortunecity.com/tinpan/humperdinck/223/memory.gif
The Electro-Harmonic Electric Mistress uses the SAD 1024. You can check the clock pulse from the components its using. It is my favorite. The WEB sight is the same as the other except that after 223/ its ehmist.gif .
Time, is on our side.
|1/2/1999 9:37 AM|
|John J. (How to tune up)|
Have you ever trimmed one of these circuits. Preferably the Deluxe Memory Man.
Yep, you guest it. The procedure please.
She's running to rich. Best to lean her out before she blows a head gasket
|1/4/1999 11:01 AM|
Bear in mind that any BBD is simply a chain of eensy-weensy capacitors, linked by FET-switches (yeah, and they SUCK TONE, man!! gimme a BBD that uses relays for TRUE bypass!! Sorry about that. Brief psychotic episode.) In order to charge up the capacitors appropriately, the signal needs to ride on a DC voltage provided by the biasing circuit ahead of the BBD. I may be mistaken, but I think that re-biasing is generally used between chips when there are several BBD's in series.
If you download the spec sheets, you'll see some info about biasing the input to the MN300x with a trim pot. It will stipulate the preferred bias voltage. Incidentally, drift in bias voltage is generally one of the first things to look for in a non-compliant BBD-based delay. Trim-pots aren't perfect, and few, if any, companies are going to use a 10-turn trimpot and scope to calibrate every single $50 flanger that pops off the assembly line.
As with anything that needs trim-pot adjustment, component values are often selected so that the "magic" spot is somewhere in the middle 25% of the trimpot's sweep. You can often just set the trimpot to the mid-point and be close enough for rock and roll, but tuning it with a scope and specs on hand is likely to yield the most satisfying tone.
|1/4/1999 12:18 PM|
The Electro Harmonix Deluxe Memory Man circuit, appears inticate in it's design as oppose to the others of this type. I use the Flanger for certain songs and noted that the five controls on the Memory Man might add a little more dimension for my tracts.
I was just concern with the alignment procedures for building this device. It sounds as though it's not as critical as I thought. If the calibration seems off. I will consult you again on this issue and locate a manual.
I must have overlooked the trim-pot on the MN300x from the data sheets. I'll look into that now.
Thanks for the Input.
For every tomorrow there is a yesterday.
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