Voltage of the VCO incorrect?

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diplowave
 
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Voltage of the VCO incorrect?

Post by diplowave »

Hello, I have voltages that are not exactly as they should be. At r105 I have 9,92volts instead of 8.5 Volts.

Image


And S1 is 6,14 volts instead of 7 volts.

Image

I think there's a problem. I don't know if it's good or not good.


But i've a sawtooth wave:

Image

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mmm
 
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Re: Voltage of the VCO incorrect?

Post by mmm »

This might all be completely ok because the voltages there are AC on a DC offset. Since the multimeter displays an RMS DC voltage the results depend on the frequency of the AC voltage (read: the note being played). At least that's what I think.

The sawtooth looks a bit funny but this may be the scope or the test lead.

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diplowave
 
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Re: Voltage of the VCO incorrect?

Post by diplowave »

Thank you, I doubted a little bit because I assembled another x0x few days before this one, and it had better voltages.
The sawtooth funny i think it comes from the mini display osciloscope, because with my Beckman 9012 the sawtooth is 100% OK.
Excuse me for my bad "speak" English, because i'm french.

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diplowave
 
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Re: Voltage of the VCO incorrect?

Post by diplowave »

I changed the thermistors, all is back to normal. Voltages are OK. :D

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