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Help with RF impedance bridge

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neazoi

neazoi

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Hello, I have made this small impedance bridge **broken link removed**
The DC out is taken from the negative terminal of the diode. The positive terminal is grounded with a resistor. This outputs a negative output voltage.
I has wondering, if these connections could be reversed so I can get a positive voltage output. That is, take the DC out from the positive of the diode and ground the negative with a resistor?
 

Hi,

i just read some of your articles they are nice (oscillator).
I just wonder why don't yo try to reverse the diode (those one between the two 270pF)?.

Sincerely,
 

perlinpinpin said:
Hi,

i just read some of your articles they are nice (oscillator).
I just wonder why don't yo try to reverse the diode (those one between the two 270pF)?.

Sincerely,
Click to expand...

I have found this design in the net, it is from a commercial bridge and I do not know why they used negative voltages.
Yes, I agree, it is easier to just reverse a diode rather than to alter the circuit. I hope Z1 and Z2 remain unchanged after this alteration.
I guess I can also do it with the RF input diode as well?

Why did they do it negative...
 

perlinpinpin said:
Hi,

i just read some of your articles they are nice (oscillator).
I just wonder why don't yo try to reverse the diode (those one between the two 270pF)?.

Sincerely,
Click to expand...

I reversed the polarity of both diodes. from testing is seems that it work perfectly ok, outputting a positive voltage instead of negative.
It seems straight forward.
 

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