[ARC5] ARA heater configuration

[AKLDGUY .]

I have a CBY-46105 receiver (3-6 Mc/s) of ARA type. The heaters were
long ago rewired for 12V and I'm investigating the possibility of a
restoration to 28V so that it will run on the dynamotor with a single
28VDC supply.

It's surprisingly difficult to locate a heater circuit configuration,
even assuming it's the same as AN/ARC-5. Is anyone able to supply a
link?

Otherwise, details of pin connections and heater line run would be
really helpful.

73 de Neil ZL1ANM