What's this thing do?

[jr_tech]

Originally Posted by old_tv_nut

It's hard to believe it could operate at 60 Hz for small capacitors, especially the mmf scale.

The Heathkit C-3 just uses 60 Hz from a 55 Volt winding on the transformer... reads down to 10 mmf.

jr

[old_tv_nut]

Originally Posted by jr_tech

The Heathkit C-3 just uses 60 Hz from a 55 Volt winding on the transformer... reads down to 10 mmf.

jr

Interesting - I believe you, but still hard to -

Reactance of 10mmf (10pf) at 60 Hz = 265 Megohm
Maximum current at 55 volts is 0.2 microamps

Reactance goes down to 16 Megohm at 1 Khz, still a pretty big number