[radio1]

It's a low circuit loading, high gain amplifier with speaker - allows to listen in and isolate defective stages, observe gain stages, find noisy parts. The detector probe has  one 6AQ6 grid leak tube, the lens rotates for different setting of capacitance or resistance. The output can connect to a multi-meter and possibly a scope. The 7030 was a better looking unit.  Most of the caps are wax paper types, but one is a bumble bee paper in oil I think.