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Subject: Re: [PolySix] Re: Noisy Polysix

From: Eoin O'Callaghan <cliofreak@yahoo.com>
Date: 2015-09-04

Ive put it together again and its exactly the same. 367 chip 18 is fine. The chip I was working on is the one right beside the battery except on the next board (366). Its a HD14069UBP



On Friday, September 4, 2015 3:02 PM, "backshall1@bellsouth.net [PolySix]" <PolySix@yahoogroups.com> wrote:


 
It looks like IC18 on the 366B is a TL072 (8-pin chip) in the tuning circuit. He was definitely talking about the 367 board, where IC18 is the 14051 demultiplexer for the filter and envelope control voltages. Pin 11 is one of the address lines that control it. Neither of them seem to be the kind of thing that would cause the type of noise you are hearing. Can you upload a picture of the top of the board, showing the chip you are working on?
Don B.
 
Sent: Friday, September 4, 2015 9:32 AM
Subject: Re: [PolySix] Re: Noisy Polysix
 
 
Thanks, well IC18 on the 367 board is fine on pin 11 and the others, however IC18 on 366 is not fine. In fact a bunch of previous re-tracing has been done on it and currently pin 11 is not showing continuity. I dunno if you meant me to check IC18 on the 366 board?
 


On Friday, September 4, 2015 2:19 PM, "backshall1@bellsouth.net [PolySix]" <PolySix@yahoogroups.com> wrote:


 
Sorry, the KLM-367 (the programmer board) is commonly called the “digital” board since it has the A/D circuit, memory and D/A chip and the KLM-366 is the “analog” board, since it has the oscillators and filters. They both have CPU chips and quite a bit of digital circuits, so using those names can be confusing. Sometimes the 366 is called the voice board, but I think the official name is the key assigner board.
Don B.
 
Sent: Friday, September 4, 2015 8:54 AM
Subject: Re: [PolySix] Re: Noisy Polysix
 
 
366B I guess...