My first one tube regen.

I opted to make an aluminum chassis with a bottom panel instead of the more traditional wooden base. This way, I can hide some of the modern looking components and the battery packs inside. The antenna and ground will attach under the two thumb nuts on the back.

I tried the space charge operation as I was more or less building this: http://makearadio.com/tube/hikers1.php
But I was trying to use mostly what I had on hand for parts, and didn't want to build spider coil forms. I used a cylindrical, cardboard coil form about 2-1/2 in. in diameter, and decided to make the antenna coupling as a coil rather than make the antenna feed the tank circuit through a trimmer capacitor. I still installed the trimmer in case I needed it, but it is not hooked up to anything now.
I also wanted a separate volume control rather than just using the regeneration control for that.

Anyway, it worked OK, but the overall performance was about the same as a decent crystal set--hooked to the same outdoor antenna and earth ground, and on the same (AM broadcast) band. I have no problem listening to a good crystal set for hours at a time, but for having to buy a tube and put in batteries, I wanted more volume in the headphones and a bit "tighter" selectivity.

Down below the pictures here is the modified schematic. I hooked up the type 49 screen grid tube as a triode, boosted the B+ to around 30 volts, the filament voltage to the normal 2 volts, and am using the actual control grid as a grid leak detector now instead of an accelerator grid. All the batteries are neatly tucked inside the chassis, and the receiver works fantastically for a one-tube device!

I love to build regeneration radios.  Looks great so far.   One of the things I've read about is having a metallic face so your hand will not effect the tuning, but I've not had an issue with it.

What do you use to draw your schematics?

Thanks!
These are fun...I'm hooked. After I build an auxiliary loudspeaker amplifier for this one, I may try a solid state regen.

I just draw them up on MS paint and then soften the look with GIMP2. The latter is a freeware kind of Photoshop.

Nice job. Wanna build one for me???

Thanks Bill!

Bill Cahill wrote:Wanna build one for me???

I'll put it on my "to do" list.

Looking good, even better with the coke bottle!

The book Radio for the Millions by the editors of Popular Science in 1945 has an assortment of one tube radio projects. Quite interesting to page through. It was reprinted in the early 1990's. I have the reprint and an original I got for Christmas one year.

75X11 wrote:Looking good, even better with the coke bottle!

Thanks...I went out of my way to get that look. I had to order the tube and the socket separately. I'm sure I have plenty of more common tubes on hand that would work, but no 5 pin ST bottles.

Doug Burskey wrote:The book Radio for the Millions by the editors of Popular Science in 1945 has an assortment of one tube radio projects. Quite interesting to page through. It was reprinted in the early 1990's. I have the reprint and an original I got for Christmas one year.

Nice!
There are a few free downloads kind of like that here:
http://www.tuberadio.it/docs.htm
But I still like paging through the paper books.

Ragwire wrote:Thanks Bill!

Bill Cahill wrote:Wanna build one for me???

I'll put it on my "to do" list.  

Thanks.........