Same insides as the G402 and G403 grams.
Intermediate Frequency: 470kc/s
Frequency Bands: 1
Chassis Notes(most schematics can be clicked to download a full size version)
Service information (Murphy_M401_Minstrel_G402_Melodeon_G403_Melodist_-_6V_BC_AC_-_1958.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 broadcast band only. Dashes and spaces seem to be used in some places while not others - ie: SG1387 is the same as SG 13-87