Synth-DIY Yahoo! Groups Archives

cs-50 vcf calibration

2013-09-18 by <rikard.latvala@...>

Hey,

I am working on a CS-50 that had several problems with the trimpots on the M boards. I have installed new ones and replaced them all with multiturn one's. I have almost completed the calibration procedure but hit a problem when i got to the vcf calibration. The CS-80 calibration procedure states that i should get 4.0 Volts moving the cutoff lever on the front panel and measuring at R51 or R52. The only marked resistor i can find on the M boards is R6 and R7, others only have their resistance marked. Any one know witch ones they are talking about ?

At point (FH) F1 on cs-50 i only have 0.003 - 0.12 volts so i can not get the 4.0 volts there no matter how the cutoff lever or trimpot is set. Could it be before the 330 ohm resistor ? (actually a 230 ohm one in the cs-50).

Please help, I really want to close it up and get it back to its owner. I am thinking about gathering all the calibration data and make a much clearer procedure as much of the info in the calibration manual is wrong.

Re: [yamahacs80] cs-50 vcf calibration

2013-09-18 by Robert Stewart

Hi

It's not talking about resistors at all. R51, and 52 are boards. They are the register circuits for the two voices.
R51 for the top row, R52 for the bottom row.

You need to look FH terminal for High pass, and FL terminal for low pass adjustments.

Hope that helps

B

I am working on a CS-50 that had several problems with the trimpots on the M boards. I have installed new ones and replaced them all with multiturn one's. I have almost completed the calibration procedure but hit a problem when i got to the vcf calibration. The CS-80 calibration procedure states that i should get 4.0 Volts moving the cutoff lever on the front panel and measuring at R51 or R52. The only marked resistor i can find on the M boards is R6 and R7, others only have their resistance marked. Any one know witch ones they are talking about ?

At point (FH) F1 on cs-50 i only have 0.003 - 0.12 volts so i can not get the 4.0 volts there no matter how the cutoff lever or trimpot is set. Could it be before the 330 ohm resistor ? (actually a 230 ohm one in the cs-50).

Please help, I really want to close it up and get it back to its owner. I am thinking about gathering all the calibra tion data and make a much clearer procedure as much of the info in the calibration manual is wrong.

Re: [yamahacs80] cs-50 vcf calibration

2013-09-18 by Robert Stewart

Sorry... Misread your Email.

On the CS50 the card you need to look at is R6 I believe.
Terminals FH, and FL

B

On 18/09/2013 10:02, rikard.latvala@... wrote:

Hey,

I am working on a CS-50 that had several problems with the trimpots on the M boards. I have installed new ones and replaced them all with multiturn one's. I have almost completed the calibration procedure but hit a problem when i got to the vcf calibration. The CS-80 calibration procedure states that i should get 4.0 Volts moving the cutoff lever on the front panel and measuring at R51 or R52. The only marked resistor i can find on the M boards is R6 and R7, others only have their resistance marked. Any one know witch ones they are talking about ?

At point (FH) F1 on cs-50 i only have 0.003 - 0.12 volts so i can not get the 4.0 volts there no matter how the cutoff lever or trimpot is set. Could it be before the 330 ohm resistor ? (actually a 230 ohm one in the cs-50).

Please help, I really want to close it up and get it back to its owner. I am thinking about gathering all the calibra tion data and make a much clearer procedure as much of the info in the calibration manual is wrong.

Re[2]: [yamahacs80] cs-50 vcf calibration

2013-09-18 by rikard.latvala@...

Hey,

After some research what they meant by R51-52 was the boards and not resistors.
Found FH and FH points on the R2 ( in the CS-50 and maybe 60 ??) BOARD ;) ... Darn it why
name boards after common shorts for electronic parts ... To much sake perhaps

-----Originalmeddelande-----
Från: "Robert Stewart" <bob@...>
Till: yamahacs80@yahoogroups.com
Datum: 2013-09-18 11:26
Ämne: Re: [yamahacs80] cs-50 vcf calibration

Sorry... Misread your Email.

On the CS50 the card you need to look at is R6 I believe.
Terminals FH, and FL

B

On 18/09/2013 10:02, rikard.latvala@... wrote:

Hey,

I am working on a CS-50 that had several problems with the trimpots on the M boards. I have installed new ones and replaced them all with multiturn one's. I have almost completed the calibration procedure but hit a problem when i got to the vcf calibration. The CS-80 calibration procedure states that i should get 4.0 Volts moving the cutoff lever on the front panel and measuring at R51 or R52. The only marked resistor i can find on the M boards is R6 and R7, others only have their resistance marked. Any one know witch ones they are talking about ?

At point (FH) F1 on cs-50 i only have 0.003 - 0.12 volts so i can not get the 4.0 volts there no matter how the cutoff lever or trimpot is set. Could it be before the 330 ohm resistor ? (actually a 230 ohm one in the cs-50).

Please help, I really want to close it up and get it back to its owner. I am thinking about gathering all the calibra tion data and make a much clearer procedure as much of the info in the calibration manual is wrong.