[sdiy] Question for Yamaha tech?

[Bob Weigel]

Yeah I did a little research but not exhaustive.   A lot of Yamaha chips 
I think were made for their purposes. Their filters, vco's, ota's....I 
mean I have enough for my stock right now barely, but if anyone knows 
ANYTHING having to do with xref'ing any of these I'd sure love to hear 
about it.  I'm 99.99% certain that the filters and VCO's are oem designs 
in cooperation with Yamaha and that there are no replacements.  I 
mean...c'mon we're talking about 1975 when these would have started into 
production right?  -Bob

Ken Stone wrote:

>I would suggest that it is a mitsubishi chip, looking at that number. Yamaha
>seems to have IG numbers for chips as common as the 4558, so that could
>merely be Yamaha's internal reference.
>
>Ken
>
>  
>
>>Hi guys,
>>
>>Tried this one at AH, but no smile so far. Maybe I have more luck here.
>>
>>Does anybody know what kind of IC this is:
>>M51620P (8-dip)
>>
>>It also says YIG8531 which, on the one hand, looks like a date code, 
>>but also has the letter markings that suggest it to be one of the 
>>Yamaha IG chips.
>>
>>Of Google was my first try, which gave absolutely zero returns except 
>>one. The most surprising part was that there wasn't even a single 
>>question from anyone about it, something you will *always* encounter 
>>when a chip is rare.
>>
>>The one entry was from sounddoctorin (yes, you Bob), but it gave no 
>>info except the entry M51620P/IG00150, suggesting it was the same as 
>>this Yamaha lfo.
>>
>>Anyone?
>>
>>Thanks,
>>Senso
>>
>>PS: With all the information on the web about synthesizer parts, how 
>>come there is virtually nothing about Yamaha's integrated circuits?
>>I'd like to know more about the rest of the M516xx series as well...
>>
>>-- 
>>
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>_______________________________________________________________________
>Ken Stone   sasami at hotkey.net.au or sasami at cgs.synth.net
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