I have this ancient early '30's boatanchor of a ham radio that I'm reluctant to start powering up even with a Variac, because the manual says not to apply power unless the speaker is plugged in first. The thing is, I don't have the speaker with a four-pronged plug, let alone one with a 6000 ohm field coil, like the manual says this one requires. Any ideas on how I can use a common 8 ohm permament type speaker? Also, the jack on the side seems to be for a phonograph attachment and not for a headphone like I thought. no 'phone jack at all for that matter.

My thanks in advance to those more knowledgeable than I --

Chris P.

Your radio uses a field to supply B+ to the 59 tube, screen. A resistor could be used in place of field. This tube pin should also have a cap to ground.

You can replace the speaker with a modern 8 ohm PM type and an audio output transformer. Almost any output transformer for a tube radio will be ok.

Without these connections voltages will be very high in your radio.

Checking the schematic will show more about the jack.

http://www.nostalgiaair.org/PagesByModel/091/M0013091.pdf

Norm

:Hello All --
:
:I have this ancient early '30's boatanchor of a ham radio that I'm reluctant to start powering up even with a Variac, because the manual says not to apply power unless the speaker is plugged in first. The thing is, I don't have the speaker with a four-pronged plug, let alone one with a 6000 ohm field coil, like the manual says this one requires. Any ideas on how I can use a common 8 ohm permament type speaker? Also, the jack on the side seems to be for a phonograph attachment and not for a headphone like I thought. no 'phone jack at all for that matter.
:
:My thanks in advance to those more knowledgeable than I --
:
:Chris P.