Advance model B4B Signal Generator


Covers 30kHz to 30 MHz in 6 switched ranges with a calibration accuracy of +/- 1% of the scale reading. The modulation can be internal (400 Hz) or external (10 Hz to 10 kHz). The meter is used to monitor the modulation (0-80%) or the RF amplitude.
It has 3 Valves: ECC91 6SN7GT and 6X5GT


views of the interior with screening covers removed (lots of screws to undo)

Two capacitors that needed replacement  and an advert for an earlier model dating from 1948

Advance made versions of this very popular signal generator for many years, I think mine dates from early 1961 based upon the date codes on the capacitors. Capacitor dating codes can be found here. Later models have rectangular meters and BNC coaxial connectors.

How much is it worth? Instruments such as this are of little use today and not many people seem interested in them. Expect to pay £15-£25.