5-valve dual wave radio.
Similar in appearance to the HMV and Astor model 616 (by Akrad Radio), however the similarities end with the appearance.
Intermediate Frequency: 470kc/s
Frequency Bands: 2
Chassis Notes(most schematics can be clicked to download a full size version)
Service information (Murphy_MD54_Minx_-_5V_DW_AC_-_1959.pdf) here
General Construction Notes for Allied Industries Ltd (Fisher & Paykel):
Murphy stereogram model prefix indicates radio bands - ie: SGA is Stereogram All-Wave, SGD is Stereogram Dual-Wave. SG means Stereo broadcast band radio only (stereo referring to the record player - radio was only mono. Dashes and spaces seem to be used in some places while not others - ie: SG1387 is the same as SG 13-87
Dating Murphy equipment is a little difficult due the codes not appearing to contain dating info. Here is what can be seen from the models examined:
SGx61x (ie SG615, SGD618) radiograms seem to have run from 1959 through until 1961/62 and used Garrard Type A record changers (these were released approximately 1959)
The first digit or digits seems to reflect the number of active devices (ie: SG 14-32 has 14 transistors, SG615 has 6 valves)