D
David King
- Jan 1, 1970
- 0
I have a notebook computer with line level input. I would like to use
shareware PC based oscilloscope software designed to input to the
soundcard ADC via a switchable attenuating amp. Yes, I do know the
limitations with this.
The problem with these setups is how to avoid inadvertently damaging
the card with over voltage. IOW if the attenuator is manually set too
low or the signal level suddenly changes.
Can someone possibly recommend a circuit for a suitable automatic gain
control such that it would not significantly alter the acquired
signal?
My frequency of concern is 20-500Hz at 1-5Vpp. Typically these devices
run off 5V available at the games or USB ports.
There are several circuits for the basic principle on the net, some
use a clipping indicator, or zeners for crude limiting, but I always
wondered why no ACG. That would be a logical and welcome addition.
Can anyone help?
Dave King
shareware PC based oscilloscope software designed to input to the
soundcard ADC via a switchable attenuating amp. Yes, I do know the
limitations with this.
The problem with these setups is how to avoid inadvertently damaging
the card with over voltage. IOW if the attenuator is manually set too
low or the signal level suddenly changes.
Can someone possibly recommend a circuit for a suitable automatic gain
control such that it would not significantly alter the acquired
signal?
My frequency of concern is 20-500Hz at 1-5Vpp. Typically these devices
run off 5V available at the games or USB ports.
There are several circuits for the basic principle on the net, some
use a clipping indicator, or zeners for crude limiting, but I always
wondered why no ACG. That would be a logical and welcome addition.
Can anyone help?
Dave King