Cheap Volt Meter Input Impedance

[a soBer Newt]

So I am working on a test fixture for production programing and voltage trimming. I was planning on using the cheap self powered panel meters you can get from All Electronics. The problem is that they draw to much current from the circuit at the trim points or their input impedance is to low and is drawing the 4V it should be down to about 2V. I was thinking about doing some simple buffers but I am worried about drift or any additional DC offset from the buffers.

Would it be better to just hack a cheap DMM in instead of the panel meters and a switch to change between the test points?

Any recommendations for some different panel meters?

 

[JohnRoberts]

It depends on the resolution you need, and if you have adequate DC rails available. A simple op amp buffer can give you arbitrarily high input impedance, and low DC voltage offsets.

JR