Overview
Built from a 1943 Silvertone radio model 6256B with original handle and knobs. As much silver color is used in the build to carry the silver theme. A modern chassis is aged to match the patina of the cabinet. A 1 watt push pull single channel with tone, master and volume control. Incredible tone and bite. Warm and articulate.
A period correct silver Jensen 6x9 ceramic speaker is mounted on a birch ply baffle connected with a silver twisted pair to provide the biggest speaker possible for incredible tone and depth. Point to point hand wired circuit uses a parallel plate single ended 12AU7 output tube driven by a 12AY7 preamp tube. The power supply uses a period correct silver power transformer driving a 6CA4 tube rectifier. An external 16 ohm speaker cabinet can be connected for additional volume and depth.
Original Radio
The SiIvertone 6256b was a four tube AM radio that was powered by batteries. It was produced around 1943.
Cabinet Repair
An opening was cut for the larger speaker and blended to match the original cabinet tweed. Vintage speaker grill cloth is mounted to the speaker baffle.
Chassis is mounted perfectly between cabinet spacers. The chassis is attached with a couple of screws from the underside. Holes are added to the cabinet through the chassis for the Volume, Tone and Master Volume and input jack and pilot light. A third matching knob was found to keep a consistent look with the original radio.
Chassis
The output transformer is mounted inside the chassis
The front gets some crack repair and some amber varnish. Looks deeper and still represents a great period patina.
Nice backside cutout
With a big bottle 12bh7 in output tube position there is slightly more gain but needs a little more heater current.
References
1 Design Inspiration and Notes https://robrobinette.com/Deluxe_Micro.htm
2 Radio Info https://www.radiomuseum.org/r/sears_roeb_silvertone_6256b.html
