I am getting ready to work on a circa 1937 Sentinel Model 52 table top radio that someone else has previously butchered. All the paper caps have been removed. Does anyone know what make/manufacture the original paper caps were used in 1930s Sentinel radios? Did they have their own branded caps, or use other generic caps like Sprauge? Also, this radio has a bias cell where prior restoror installed a watch battery. Is this a proper replacement for a bias cell?
Thanks,
Britt

Last year I did a Sentinel 269T from the late 30's. It had blue-label Solar molded plastic caps.

If the watch battery matches the specified bias cell voltage, it should do, so long as it's properly installed for polarity.

Larry

Thanks Larry, did these Solar caps look like the plastic bumble-bee style plastic caps?

Britt

NO, the Solar caps are a light brown, and the wrapper slips over them like a crayon wrapper.

Right, and the molded plastic bodies themselves often looked sloppy, as if somebody made them by hand instead of by machine.

L

If the bias cell goes between grid and ground, you can likely replace it with a 10 Meg resistor and get rid of it entirely. If it's floating, though, you'll need to keep the battery there.

Guys thanks for the info... I re-looked this chassis over and it also has three of the raised tube shield mounts riveted to the tube sockets where the tube shield fit over top in friction mount. Two of these are missing and have two square philco tube shields mounted with grounding strap wires soldered to ground. The more you look....the more you find...maybe I will put this one off awhile and pick a simpler project like my Zenith 8S443 table set.
Britt