Rhodes Chroma Polaris

Hello.  I am new here.  Can you help me with direction on finding a mother board for my chroma polaris? "SHARIFAH"
THE NOBLE, THE HONORABLE 

     On Wednesday, February 18, 2015 8:16 AM, "bob@...m [chromapolaris]" <chromapolaris@yahoogroups.com> wrote:
   

     Hi.

I'm working on a Chroma Polaris, and it seems to have a faulty resonance issue.

By the time the slider is at the half way mark I'm on full resonance, and I only seem to have 4 steps. This is same for all voices.
Being a tech, I've been probing around trying to see what's going on.

If I look at the signals coming off Z49, I'm not getting anything on Pin 3 which is the ResA line.
The input (17) to this looks fine.
I've swapped the chip and still no change. If I lift the leg and probe I still get nothing on the scope, so It's not being pulled down.

If I look at the output of Z80 (pin 6) it appears to be stuck high. and tracing back, the (Not) PCS6 line is static.

I may be looking in the wrong areas, and barking up the wrong tree.

Anyone else had this issue, and solved it?

Any pointers would be most helpful.  #yiv8536330642 #yiv8536330642 -- #yiv8536330642ygrp-mkp {border:1px solid #d8d8d8;font-family:Arial;margin:10px 0;padding:0 10px;}#yiv8536330642 #yiv8536330642ygrp-mkp hr {border:1px solid #d8d8d8;}#yiv8536330642 #yiv8536330642ygrp-mkp #yiv8536330642hd {color:#628c2a;font-size:85%;font-weight:700;line-height:122%;margin:10px 0;}#yiv8536330642 #yiv8536330642ygrp-mkp #yiv8536330642ads {margin-bottom:10px;}#yiv8536330642 #yiv8536330642ygrp-mkp .yiv8536330642ad {padding:0 0;}#yiv8536330642 #yiv8536330642ygrp-mkp .yiv8536330642ad p {margin:0;}#yiv8536330642 #yiv8536330642ygrp-mkp .yiv8536330642ad a {color:#0000ff;text-decoration:none;}#yiv8536330642 #yiv8536330642ygrp-sponsor #yiv8536330642ygrp-lc {font-family:Arial;}#yiv8536330642 #yiv8536330642ygrp-sponsor #yiv8536330642ygrp-lc #yiv8536330642hd {margin:10px 0px;font-weight:700;font-size:78%;line-height:122%;}#yiv8536330642 #yiv8536330642ygrp-sponsor #yiv8536330642ygrp-lc .yiv8536330642ad 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