Regen receivers of the past.

[Reece]

A very popular set in the early twenties was the Radiola III two-tube, one stage of regenerative detection and a stage of audio. The III-A added two more tubes and could drive a speaker. I have a III from 1924 and it easily picks up anything an ordinary superhet can all over the eastern U.S. at night with just fifteen feet of wire. It doesn't like too much antenna which tends to load it down and keep it from regenning.

There are countless versions of regen circuits and much written about them. They were popular with amateurs even into the 1930's due to the great sensitivity possible with few components. The touchiness in operation can be reduced with proper shielding and often a regenerative detector tube "likes" a particular B+ voltage for smooth operation: often voltages from 12 to 22 volts work better than higher voltages.

[catman]

G'day all, well I finished it this afternoon, built on a wooden 'cutting board'. It works well but the setting of the regeneration trimmer capacitor is critical! Regards, Felix (vk4fuq) aka catman.

[dieseljeep]

Originally Posted by wa2ise

Think I have a Philco that used some superregenitive action in the IF amp stage. IIRC (and a good chance I don't) it was this one:

It had a knob on the back of the chassis that could adjust the gain/superregenitive action of the IF tube.

The Philco model 57, was my mother's first radio. It used an autodyne converter and regenerative IF setup. There was a knob on the back, but it was a band selector. The regeneration setting was a trimmer on the back of the chassis. The Philco model 80, 84 and 37-84 was similar. They were referred to as Philco Jr's.

[dieseljeep]

BTW, Don't forget about all the CB sets and the "Benton Harbor" lunch boxes, that were popular in the late 50's, early 60's.
The Fremodyne FM receivers of the late 40's, early 50's.
Also the German "peoples receivers".

[old_coot88]

Originally Posted by catman

G'day all, well I finished it this afternoon, built on a wooden 'cutting board'. It works well but the setting of the regeneration trimmer capacitor is critical! Regards, Felix (vk4fuq) aka catman.

Cool.
If you use a pot across the tickler instead of a trimmer cap, it makes adjustment much less finicky. Also doubles as a volume control. I always used a 50K pot.