February 14th 09, 03:01 PM
posted to rec.radio.shortwave
|
|
external usenet poster
|
|
First recorded activity by RadioBanter: Jan 2009
Posts: 5,185
|
|
1920's radios ???
Michael wrote:
"Brenda Ann" wrote in message
...
"Michael" wrote in message
...
I've never heard/read a single thing about 1930's battery radios. The
ones I know about were all from the 1920's. They take the 201 and 301
tubes. Most were made to take 6.5 volts for the filaments as car battery
rechargabe wets of the time were all 6.5. Here is the interesting thing.
Those tubes dont need that much juice. The rigs bump it down from 6.5.
There were some 201 and 301 tube radios that have direct voltage to the
tubes. If you hook up 6.5 volts to the filaments, kiss the tubes
goodbye.
01A/201/301/etc. used 5V filaments. Many radios using these tubes ran
6.5/6.6V auto batteries and had an adjustment to allow for voltage to the
filaments to be varied so that as the battery ran down, you could turn the
voltage back up a bit, thereby getting longer use out of a charge of the
battery.
I was mistaken about those tubes, then... I thought the 01A filaments took
less then 5 volts.
Michael
http://www.xs4all.nl/~tgale/oradio/faq3.html
|