I picked up this Class C wavemeter at the hamfest , it was 20 bucks . I have had a few of these .
I am not sure if this unit is based on a UK design ? Anyway all of them Ive seen are dated 1941 and they were made by AWA Sydney .
Each set came with a spare valve , the spare valve and its box are marked the same serial nr. as the set is .
The power plugs are the same pattern as the AWA 101 set .
Each set came with a calibration chart - the chart slides into a thin pocket next to the PSU . These sets are next to useless as a wavemeter, you would be lucky to get within 20 khz of an assigned frequency .
The set runs from a 6 Volt battery , the vibrator HT unit is on the left with a spare vibrator .
This set has been painted grey post war . Inside the calibration chart envelope, I found a consignment note from TAA airlines from 1948 ! The note details shipment of this set from Brisbane to HM prison Adelaide !
Edit: Just found this similar unit , I think its a British made unit
http://www.zc1-radioclub.org.nz/wave_meter_class-c.htm
Also this one I cannot read Dutch
http://www.pa3esy.nl/military/gb/arm...ave_c_set.html