SKYMASTER 5M4 (1954)

The Skymaster 5M4 was manufactured for Bond & Bond Ltd by Akrad Radio Corporation Ltd in 1954.

Akrad put through a special run of their 5M4 Clipper Junior for Bond & Bond, the only real difference being the dial, just as with the Skymaster version of the Bell Colt.

Note that the only sighted chassis used in the Skymaster versions are the early model.

Valves (5): ECH42, EF41, EBC41, EL41, EZ40

Frequency Bands: 1

Chassis Notes(most schematics can be clicked to download a full size version)

There are at least two main chassis variants, both using almost the same circuit and the same valve lineup, and can be seen in here with the older variant at the bottom.

1954 Clipper 5M4

1954 Clipper 5M4

The earlier chassis has the serial number stamped on the back while later models have a serial plate riveted on.Earlier models also have round IF cans, where the later models use more modern rectangular units.The later models have a Rola 5" speaker providing feedback to the 1st audio section via a resistive divider and also have an internal foil antenna glued to the inside of the cabinet and attached by a small bolt and nut in addition to the external orange aerial wire where the earlier models have no feedback and just the external orange aerial wire (both have a black earth wire as well).A few other minor variations have been noted, such as Ducon capacitors in the earlier models with mustard caps in the later and a metal shield over the dial lamp in the later ones, presumably to try and cut down on the amount of glow through the cabinet, and / or cracking or deforming due to heat.

1954 Clipper 5M4

1954 Clipper 5M4

General Construction Notes for Akrad Radio Corporation Ltd:

Akrad sets often consist of 3 (or 4) numbers (eg: 518, 1059) or number-letter-number (5M4), and a common pattern exists for these sets: The first digit(or 2 digits in the case of 10-or-more valves) is the number of valves, the second is the number of bands and the third is the last digit of the year. Where the middle digit is a letter rather than a number it generally refers to the type of set - M for mantle, P for portable, G from radiogram etc

Often sets can be dated by the speaker, as many Akrad sets from the Pye era have the date of manufacture stamped on the back of the magnet housing.

All documented models using this chassis (3 in total)

1954Clipper 5M4
1954Skymaster 5M4 - this set
1955Clipper 5W5