physicsAAS
Newbie level 1
Hi,
I have a SIM9800 analog summing amplifier. I have a DC source meter and AC lock-in amplifier. I connect the output to a resistor. I want to tune the DC source while modulating a constant AC source. The lock-in can measure the current or voltage; I want to measure the current.
So after making the necessary connections, I begin to tune. Around V = 0 the AC current reading on the lock-in is constant as expected, then at some critical value of voltage, it just drops to zero.
Can someone help what could be the cause of this problem? Neither the lock-in or summing amplifier show a voltage overload input.
I have a SIM9800 analog summing amplifier. I have a DC source meter and AC lock-in amplifier. I connect the output to a resistor. I want to tune the DC source while modulating a constant AC source. The lock-in can measure the current or voltage; I want to measure the current.
So after making the necessary connections, I begin to tune. Around V = 0 the AC current reading on the lock-in is constant as expected, then at some critical value of voltage, it just drops to zero.
Can someone help what could be the cause of this problem? Neither the lock-in or summing amplifier show a voltage overload input.