my ugly 3 tube regen.. Works!

[jbivy]

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Older picture of it partially wired, i mounted the transformer up top so.. i had to stick one of the tubes in the chassis. Its a cx-301-a detector with two 201a finals.

[bob91343]

Nothing ugly there. Where did you get those knobs and the dial? I'd love to get my hands on some of those.

[jbivy]

I just lowball maybe a dozen ebay parts at once and.. slowly i got them on the cheap. You eventually win a few pieces for the low offer. Anyhow, none of the parts are mint, all have little flaws, but none that effect performance in any way.

When im sure this circuit doesnt need to be modified anymore, ill build a nice case and panel for it.

[Sandy G]

Yeah...If THAT'S "Ugly", I wonder what your "Purty" is...That looks Fine 'n' Dandy to me ! (grin)

[Reece]

Is that an ICA plug-in coil? That looks like either the broadcast or 160 meter coil. I had a set of those going up into short wave back in the fifties. What can you get on the set? What antenna are you using? Lots of times regens don't like a real long antenna unless you stick a varicap in series so it doesn't load down the detector too much and won't let it get close to oscillation. Tell us what bands you've been on and what you can get! Lots of fun with these sets.

[jbivy]

Well on the IC standard broadcast coil i can identify seven stations. The other is a "1900-940kc" that doesnt seem to pull in much of anything, can i test it for continuity? My current antenna is 53 feet of 14gauge stranded copper wire hung about 30 feet tall, insulated on both ends, with a feeder line going to the antenna at roughly 6 feet. Grounded with the same wire, run down and wrapped around a piece of rebar i ground shiny, then pounded it a good two and a half feet into the ground. Ive got a .005 cap between the antenna and radio, it seems to like that.

Id draw out the schematic but its just a simple regen circuit with a thoradson 3:1 transformer in between the cx-301a detector tube and the two 201a finals. Id have to check it out to look up all the parts that its made of, but the only true deviation ive done is that variable capacitors are all a bit higher than called for.

My wiring is still a complete knot of wires. Im debating just tearing it apart and mounting everything in an old empty 6 tube wood radio that still has a front panel. It would look classier and possibley be easier to rewire and have it actually look decent. Maybe add a tiny transistor amp for the final, so i could run a speaker easily.

oh and one last thing, how do you stop the urge to start another radio before the last one is finished? I picked up three matching uv199 sockets and a breadboard 9 tap varicoupler. Basically enough stuff to start a new radio. Possibly build a crystal radio with three uv199 finals?

[Reece]

That's a good antenna, should work well with anything. No problem jumping from one set to another: after all it's not a job, it's for enjoyment and for more knowledge/experience that will help the enjoyment. All guilt banished!

A three-tube set should run a speaker directly if it's running efficiently. An '01A tube doesn't have a lot of oomph as an output amp, but it's sufficient for enough volume in a small room. With a PM speaker you need an output transformer; use anything you have around, like one out of an AA5 junker.

At night you ought to try the coil that tunes 9-10 Mc, should be some short wave broadcasters on there.

EDIT: As I recall those ICA coils were for use with 140 pf or mmfd tuning cap. If you're using a 365 cap or something else they won't tune what they're listed for.

[Bill Cahill]

For an ugly radio, sure looks purty to me.
Nice work.
Bill Cahill

[jbivy]

Originally Posted by Reece

EDIT: As I recall those ICA coils were for use with 140 pf or mmfd tuning cap. If you're using a 365 cap or something else they won't tune what they're listed for.

dang.. im using all 365pf variables caps... i figured it would make no difference if they tuned higher than what was needed.

What if i changed the coil to another one? like a ferrite coil out of a junker portable? Would i still need to change the variable caps?

[Reece]

Coils should be marked for the capacitor they are to be used with. But I'm pretty sure they are for 140 pf which was often used for short wave sets. You should be able to order one of those on line or on the auction site. You could also press into service the oscillator section (the one with fewer plates) of a variable salvaged from a junked AA5 radio, which may be about 160 pf. and won't be exactly right, but closer. Using a higher value capacitor will make the coil tune lower in frequency than it's marked.

You could also put a 220 pf cap in SERIES with your 365 pf cap to reduce the max to about 140 pf.