1940 Motorola B-150 Bicycle Radio

[Dbubbleguy]

There are 3 bicycle radios using tubes (not transistors) that are really rare- The Tom Thumb Bicycle Radio, the Darb Holiday Bicycle radio, and the 1940 Motorola B-150 Bicycle Radio. Of these, I have the Tom Thumb and the Darb. The Holy Grail of these radios is the Motorola. Usually when these are offered for sale, they are in rather poor shape. There is a Motorola on Ebay that is extremely good condition. While not complete (missing the battery box), the radio itself is in beautiful shape for an 80-year-old piece of electronics. I would buy this... if I only had $2,299,99. Click on link to see the listing-

Motorola Bike Radio

 

[Ulu]

Wow! That battery box must’ve been a monster.

 

[rickpaulos]

Holy cow. Vacuum tubes. Made before Bell Laboratories newly invented transistor was available. Original price was $19.95

The schematic shows the battery pack is a multi voltage pack with A & B batteries. The A battery powers the heating elements in the tubes (1.4 volt filaments in all 3) and the B (67.5 volts) to run the circuits.

Tubes:
1A7GT Oscillator (used to make a steady intermediate frequency) and Mixer.
3A8GT (not 3ABGT) Detector - preamp
1Q5GT power amplifier

tube data sheets:
https://frank.pocnet.net/sheets/127/1/1A7G.pdfhttps://frank.pocnet.net/sheets/127/3/3A8GT.pdfhttps://frank.pocnet.net/sheets/049/1/1Q5GT.pdf
One on a bike:
http://www.gifarmer.com/bike/bike_columbia_radio.shtml

 

[Ulu]

I built a vacuum tube radio from a kit when I was in jr. high school. Motorola 5-tube Super heterodyne.

I’ve never worked with one from a bicycle, but I had one in a 53 Pontiac sedan, and I have one that’s not working yet, from my 1947 Plymouth.

Someday I may put that one in working order.