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Subject: Re: [POSSIBLE SPAM] Re: [yamahacs80] Cs80 voicecard strange behavior..

From: "Laurie Curry" <laurie@...>
Date: 2013-11-12

I am trying to recall, but as far as level adjusters, the top two were noise and vcf level the next was sine level the next overall vca level and the bottom one... dont touch... lol... that has to do with envelope timing.... my first to look at would be second pot from the bottom... but this is a 10 year old memory so if you have the m board schematic ... use my words as needed...


 

-----Original Message-----
From: "Bob Stewart" <bob@...>
To: yamahacs80@yahoogroups.com
Date: 11/11/13 03:03
Subject: [POSSIBLE SPAM] Re: [yamahacs80] Cs80 voicecard strange behavior..

 
 

Could be one of the VCA potentiometers.

Can't remember off the top of my head which one is the overall level VCA, but the pots are at the opposite end of the card from the tuning pots.
I'd start by reflowing the solder on the pot connections. I'd also clean with pots. First with IPA (Iso Propyl Alcohol) and then give them a small amount of EML (Electro Mechanical Lubricant) or similar. Of course you'll need to recalibrate the VCAs after this.
If you have access to a Scope and the schematics you could probe around the VCAs and see exactly where the signal is dissapearing.

I'm back in the workshop again tomorrow, so will have schematics etc. to hand

B

On Monday, November 11, 2013, wrote:
 

Thanks for response. The thing is there is no sound at all at first ant when it slowly comes back, it's all at once (noise and oscillators), so it can't be the separate pot level. 



---In yamahacs80@yahoogroups.com, <laurie@...> wrote:

 

the lower controls on the front of the M cards are level adjustments for different amp stages... there is one for noise level, one for VCF level, one for Sine level, and an overall level with an envelope timing one on the bottom... I suggest going to your panel on powere up and seeing if you have sine on voice 1 right away.... if you do, it is before the sine you have issue, if you dont , it is after... it could just be a simple tweak on a touchy pot...


 

-----Original Message-----
From: pyjamagroove@...
To: yamahacs80@yahoogroups.com
Date: 11/10/13 09:05
Subject: [POSSIBLE SPAM] [yamahacs80] Cs80 voicecard strange behavior..

 

There is a strange issue with my voice card 1 on channel 1. After turning the synth on it is completely mute. But after a warmup and some gymnastics ( adjusting filters, turning osc´s on and off etc.) it slowly comes back. First as a cutting noise and then as a full working voice. It is like that every time.

I think it´s not related with osc´s and filters. It´s more like an amplification problem. What could I check?