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Hi All.. New Member with A question on testing vintage DIP BBD IC's for analog delays

noirengineer

Sep 29, 2009
6
Joined
Sep 29, 2009
Messages
6
Hi all.

I'm mike. I'm a new member here.

Very cool forum you guys got here! :)


_____________________________________________________________

Anyway, introductions aside, I have a serious conundrum.


I enjoy buying vintage parts (i.e. IC's, Capacitors, Germanium/silicon Transistors,
tubes, etc.) All for the purpose of recreating vintage audio circuits, signal processors,
or, in many cases, re-creating vintage or modern types of stompbox guitar FX pedals. etc.


Look, I get it! I'm no dummy.

I mean, I understand the risks involved in buying vintage electronic components online!
But for the most part, I've learned to offset this practice (of buying duds and fakes) by
using my trusty test equipment (which cost me a small fortune btw, but was
100% worth it IMO)

So for example, if I buy a bunch of Mullard Tropical fish caps or mustard caps, etc.
I can use my trusty ATLAS ESR60 meter (measures ESR + diagnostics,
leakage etc.) to make sure they are legit and working correctly! *Also, a great tool
for 'in-circuit' cap testing, such as shorts, or leaks in electrolytic capacacitors, or for
servicing old vintage guitar amps *that might blow any moment!

It's also great for biasing circuits and such, etc..
That's because the values of the leaky caps or transistors that vary if gain
will be the "MOJO" that makes (for example) the ORIGINAL VOX TONE-BENDER
FUZZ sound good in the first place! this is useful for matching transistors by gain, etc.
biasing circuit to react different before it reaches the op-amps, etc.


So, for example, when I buy 'vintage' or even most 'modern' transistors,
such as 2N5088, to OC74's, OC75's, OC76's, BC109s, NKT-275's, etc. etc. etc.
I'll whip out my ATLAS PEAK DCA55 --> measures HFE, leakage, etc.

FANTASTIC! Right?


Well, almost...


I suspect, I have recently been burned (i.e. "ripped-off") on an auction I won
on the well-known auction site *(HINT: it rhymes with flee-bay)


Anyway, my problem exists here.
I bought several vintage IC's *out of production* -- or more Specifically,
MID-1980's production models Panasonic manufactured vintage 80's IC's

The most specific (and troublesome of these being....)
1) PANASONIC MN3005 / 4096 step BBD delay chips"
2) PANASONIC MN3101 / CLOCK IC's"


I can't fully tell if they are legit or not! They don't sound the same as the verified
chips I've A/B'ed in tests. also there is a significantly different amount of delay
time in Milliseconds between the "REAL CHIPS" vs "IMITATION CHIPS"

_____________________________________________________________________


My QUESTION IS AS FOLLOWS:

-----> IS THERE A TEST TOOL I CAN USE TO NOT ONLY VERIFY IC'S OF SUCH
NATURE, AS TO WHETHER OR NOT THEY ARE THE LEGITIMATE CHIPS.

AND FURTHERMORE! IS THERE A DIAGNOSTIC IC TESTING TOOL, IN
WHICH I CAN DO FURTHER TESTING AND REPORTS ON TO TEST IC'S?
IF SO, DO YOU HAVE ANY RECOMMENDATIONS ON SUCH A TEST TOOL
OR TOOLS THAT I'D NEED IN ORDER TO DO THE FOLLOWING TASKS?



__________________________________________________________________

Any Help is much appreciated!

Thanks again!


-mike
aka noir
 
Last edited:

noirengineer

Sep 29, 2009
6
Joined
Sep 29, 2009
Messages
6
they don't manufacture these chips anymore,
I believe they stopped manufacturing these somewhere from mid-80's
to around early 1990's. So, I'm not sure what they could do in terms of
supply or whatever. but FWIW, I believe they make a comparable chip that
is now in production, that is somewhat similar *in function*, yet,
to my ears, it doesn't sound as good, so it doesn't exactly cut the mustard imo.
 

noirengineer

Sep 29, 2009
6
Joined
Sep 29, 2009
Messages
6
Datasheets

DATASHEETS (PDF)


PANASONIC MN3005
H**P://w*w.alldatasheet.com/datasheet-pdf/pdf/87983/PANASONIC/MN3005.html

PANASONIC MN3101
H**P://w*w.alldatasheet.com/datasheet-pdf/pdf/14238/PANASONIC/MN3101.html
 

noirengineer

Sep 29, 2009
6
Joined
Sep 29, 2009
Messages
6
Sorry I couldn't include a "DIRECT-LINK" for those data sheets (above)
but, I couldn't, due to the fact I have not yet made it passed the "10-post" mark on this forum.
:rolleyes:
 

noirengineer

Sep 29, 2009
6
Joined
Sep 29, 2009
Messages
6
I think I may need to invest in some more gear :(

Sigh.. is an oscilloscope a looming inedibility in my case?

Mo' money mo' problems?

how about no' money, many problems? hehe
 
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