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I picked up this NR-6 at an auction a couple of years ago. It included the tubes and a notation that it was working and a had manual for it included. It has a great front panel, so glossy that it is difficult to photograph without picking up reflections of surrounding objects. The panel is not cracked, that is a reflection.
I just put it up on the shelf and had not tried it so I brought it into the shop for a test drive. It worked quite well but the volume seemed a little low.
An examination found that the second audio interstage transformer, a 3 1/2:1 one was open, both in the primary and secondary, and the previous owner had R/C coupled it. A did a quick rewind of the transformer and this gave a great improvement in the volume. Not knowing the number of turns originally used I decided on a primary of 3200 turns and a secondary of 11,200 turns of #41 wire. This was selected as the original coil was quite small indicating a fewer number of turns and I was afraid of winding a coil that was too large for the steel. A Hammond 124C coil would have been a good alternate choice.
The radio had all of its instruction labels present and had been adapted to use a C battery by a radio shop in Saranac Lake, New York. Instructions and a internal holder for the battery were added by the shop.
The back also had a card showing proper hook up. The jumper wire is used when only 90 volts is used on the final audio stage. With it removed 135 volts would be used.
Ed.
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