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Hello again,
These pictures do tell a lot. Your radio is a Viking
unit, marketed by Eaton's of Canada. The chassis uses a
combination of pre-octal tubes (80, 42, 76, 6A7, 6E5) and
octal-base metal tubes (6K7, 6F5, introduced in 1936). It
would appear from this combination that this radio was
manufactured around 1936-1938. The 6A7 is one of the earliest
pentagrid converter tubes, making it possible to achieve
frequency conversion (or first detection as it was sometimes
called) with a single tube.
Another interesting feature of this radio is that is does
not include any actual detector diode in its tube lineup.
Detection is probably achieved usind the 6F5 wired as diode
or an infinite impedance detector. A schematic would help.
It is most likely that your radio uses an electrodynamic
speaker, meaning that the constant magnetic field is provided
by an electromagnet rather than a permanent magnet. The
electromagnet coil also acts as a filter choke for the power
supply. There are two important facts in relation with this:
1 - High voltage is present at the loudspeaker wiring, so be
careful with broken wires, frayed insulation, etc.
2 - The radio won't work at all (except for the tube heaters
lighting up) if the field coil is open or disconnected.
This is a nice radio, and the chassis appears to be in
good cosmetic condition. I believe it is worthy of a good
restoration.
It would help very much at this point if you would let
us know what you attempted to do and what happened. Bye for now.
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