Intermediate Frequency: 470kc/s
Frequency Bands: 8
Chassis Notes(most schematics can be clicked to download a full size version) Bandspread set: 6 bandspread bands + SW + BC (and both tape and gram input). Two different eye options - EM81 or EM85 - must replace like with like or rewire to suit.
Service information (Murphy_MB302_Metroploitan_-_6V_BS_AC_-_1957.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 making much sense to the author. 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)