Motorola 58G11 Post war table radio (pre 1951).
This is a beautiful Motorola 58G11 rich chocolate brown Bakelite All American Five tube radio. This radio shows a brilliant reflective sheen. There are no cracks or scratches on the bakelite cabinet. The radio plays well and is equally sensitive across the whole AM Broadcast band from 535 to 1620 kHz.
The radio measures 6.5 inches high, 10.5 inches wide and 5.75 inched deep.
The restoration includes replacement of all Waxed/paper capacitors, Electrolytic capacitors, most of the resistors. Tubes have all been tested and a full electronic and mechanical alignment have been performed. It has also been cleaned, lubricated and operated for an extended “Burn-in” period to flush out any immediate failures.
The chassis is directly connected to one side of the power line wires (plug). It is truly a Hot Chassis radio. This radio is not good for around people who do not understand the ramifications of a chassis connected directly to one side of the power cord. See schematic for details.
This radio has been fully restored.
All tubes tested,
All waxed paper caps replaced,
All Electrolytic capacitors replaced,
All carbon composition resistors replaced.
Case cleaned and buffed with a power cloth wheel and rouge,
dial indicator gold area repainted,
Lettering refilled with paint,
Knobs scrubbed of ground in dirt and goo,
Coated with Glayzit.
Burned in for 24 hours.
This symbol on the schematic represents a wire that is soldered to the metal chassis. Look at the power cord plug symbol and trace thought the power switch to the ground symbol. If you expand the under chassis picture above, you can actually see the power cord enter the chassis, go through the knot, and attach to the power switch (rear section on the volume control).
From the switch locate the bare wire going down to a solder lug on the chassis. This is what presents the problem with transformer less AC-DC radios of this era.
All AC-DC transformer less radios share this manufacturing cost savings "feature" in one form or another. This connection may be made through a capacitor or a capacitor with a parallel resistor. But all present a problem for the uniformed or unappreciative of the implications.
Further reading on this subject can be found in Radiotron Designers Handbook, 4th edition, RDH Vol 4 at the t3h GeeK ZonE.
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