Anyone by any chance have schematic of iso phono stage, i want to change the input impedance.
The blue resistor on the left is 100r and on the right 10r, the wide area of the light green of PCB is ground plane. So i am guessing that the blue resistor is the one setting the input impedance, if that is the case is it a simple matter of changing this resistor?
The blue resistor on the left is 100r and on the right 10r, the wide area of the light green of PCB is ground plane. So i am guessing that the blue resistor is the one setting the input impedance, if that is the case is it a simple matter of changing this resistor?
Looking at the filed away IC type numbers, I don't expect the manufacturer published the schematics. If anyone has them, it must be by reverse engineering.
It is very likely that you are correct. The little yellow capacitor and the 100 ohm resistor very probably set the input impedance, and the 10 ohm is very probably a feedback resistor.
With the amplifier switched off, you could use a multimeter to check if the input makes contact with the 100 ohm. Chances are that it is connected to the yellow capacitor, 100 ohm and pin 3 of the first IC (which is probably an op-amp). Changing the impedance is then indeed a matter of changing the 100 ohm resistor.
It is very likely that you are correct. The little yellow capacitor and the 100 ohm resistor very probably set the input impedance, and the 10 ohm is very probably a feedback resistor.
With the amplifier switched off, you could use a multimeter to check if the input makes contact with the 100 ohm. Chances are that it is connected to the yellow capacitor, 100 ohm and pin 3 of the first IC (which is probably an op-amp). Changing the impedance is then indeed a matter of changing the 100 ohm resistor.
They say it has 100 ohm input impedance:
http://www.retrotechaudio.co.uk/michell-iso.html
What MC cartridge needs anything different?
http://www.retrotechaudio.co.uk/michell-iso.html
What MC cartridge needs anything different?
