Talk:Radio hat

Fabulous geek-chic from 1949! Please move to article space soon... AnonMoos (talk) 12:26, 4 March 2009 (UTC)

My goal is to have this as a Did You Know article on April 1. April Fool's Main Page/Did You Know

I will move it to article space before the end of March. Here is a first pass at the DYK hook


 * ... that the Radio Hat, a 1949 precursor of the iPod, came in Canary Yellow, Flamingo, Lipstick Red (pictured), Tangerine and four other vibrant colors?

-- SWTPC6800 (talk) 15:09, 4 March 2009 (UTC)


 * Not sure why it's the precursor specifically of the iPod (which is not usually a radio)... AnonMoos (talk) 22:47, 4 March 2009 (UTC)


 * ... that the Radio Hat provided portable music 60 years ago and like today's iPod, came in vibrant colors: Canary Yellow, Flamingo, Lipstick Red (pictured), Tangerine and four others?


 * ... that before Hope Lange's successful Death Wish, she wore this peculiar electric device, the Radio Hat (pictured)?

-- SWTPC6800 (talk) 05:01, 5 March 2009 (UTC)

More complete circuit description
The following might serve as a starting point for discussion:

The 1S5 tube serves as a regenerative receiver, with cathode feedback being supplied at a fixed level by the 330 pF capacitor. In this configuration, the detector is operated with the feedback well in to the oscillation range. When a station is tuned in, the carrier of the broadcast station "blocks" the oscillation of the detector, allowing AM broadcasts to be received without a heterodyne (squeal), even though there is no provision for controlling the amount of feedback. Note that the antenna pick-up loop is also part of the tuned circuit for the detector; this would have resulted in very close coupling of the antenna and detector and would have greatly facilitated the blocking action of the carrier.

The need for the broadcast carrier to block the oscillations probably accounts for the limited advertised range of the receiver; the regenerative detector is certainly very sensitive and capable of receiving much more distant stations, but carriers more distant than the stipulated twenty-mile range were probably not strong enough to reliably block oscillation. Skilled users would perhaps be able to receive more distant stations by zero-beating the oscillations to the broadcast carrier; however, such operation would require constant retuning and be attendant with frequent loud squeals through the earphone.

Audio extracted by the 1S5 was amplified to earphone level by the 3V4. The audio signal is dropped directly across the earphone; there are no other components in the audio output stage. Note too that the full plate voltage is dropped across the earphone. This is not much of a hazard at 22 1/2 volts, but as a side note this technique was commonly used on other radios that had ninety or more volts on the plate! —Preceding unsigned comment added by 166.128.67.168 (talk) 15:35, 12 November 2010 (UTC)

It's a Synchrodyne, not a Regen
"...but carriers more distant than the stipulated twenty-mile range were probably not strong enough to reliably block oscillation"

Actually, no.

The circuit is a common example of a Synchrodyne. If the station is tuned carefully, the local oscillator Phase Locks with the carrier by means of "Injection Locking".

In a Regen, the level of oscillation is usually controlled by means of a fillament rheostat, but without a regen control it becomes a Synchrodyne.