Anybody have a good regen schematic?

[kf6pqt]

I havent played with a regen in a while, might be neat (and save desk space) to use one on 75m.

I sure do like the looks of this, scroll down until you see a 1625:

http://www.schmarder.com/radios/crystal/58.htm

But that strikes me as  more of an amplified xtal set than a regen... or am I clueless about something here? I REALLY dig the starved-plate 1625 idea, man, thats just Daisy Duke sexy.

What other good regen ideas are out there to be seen? I'm looking for stuff on the simplistic side.

Thanks!
& 73,
Jason kf6pqt

[Ed/KB1HYS]

heres one that I've built.  One 12AT7 tube and plug in octal coils. Simple and works pretty good too, though I had to change the coil to a solenoid winding and reduced the coupling on the tickler a little to tame it.  I am adding an RF amp stage ahead of the regen to provide some isolation from the antenna. She'll be a nice little rig then!

http://www.mines.uidaho.edu/~glowbugs/12at7_regen.html

There are some other good schematics on that site for regens, and simple CW transmitters too.

Amazing how well a little one tuber can bring out AM, CW and SSB signals. 

[The Slab Bacon]

Jason,
          That is definately a regen receiver, however it is definately a little unusual to see the "tickler" winding in the cathode lead of the tube. I wonder why he used a 1625 (807) for the tube. There are certainly a lot of better choices out there. If he was looking for antique esthetics he should nave used an '01A. His schtuph seems a little strange in chassis layout, but thats the fun of home brewing.

                                                                              the Slab Bacon

[WU2D]

Jason,

I posted my first regen from "The Boys First Book of Radio and Electronics" on the First Ham Station thread. Take a look. It is a fun circuit but hardly the best performer compared to all of the super high performance regen circuits out there now. Electric Radio has had numorous regen articles over the years, some claiming to be the Holy Grail of Regens!

Almost any tube with gain can be made to work in a regen circuit! And almost any oscillator circuit can be configured to be a regen detector. BUT:

Most of the top shelf regens have a few things in common:

They are built with good quality components on a mechanically solid chassis (whether wood, plastic or metal).

The antenna coupling is very light.

The tube is usually a low Mu triode (10 - 20) with very low (15 - 35 VDC) voltage on it.

The detector tube socket may be shock mounted or damped.

The regeneration Control is a "Throttle" capacitor - not a potentiometer.

They are battery operated.

Some good tubes to try in conventional Armstrong regenerative circuits include the 26, 27, 30, 37, 56, 76, 6L5, 6P5, 6SR7, 6C4, 6BF6, 1G4, 1H4, 958 Acorn and 12AH7. Notice that the 6BF6 is included - that tube was the one from the "Boys" book. It is a fairly low Mu triode (16).

There is a whole other school of regens which came out of the early 1930's which use pentode tubes and utilize Hartley and even Colpitts circuits. High Transconductance sharp cutoff tetrodes and pentodes were popular for this circuit type. Tubes like the 24A, 32, 36, 58, 78, 6J7, 6K7, 6SF7, 6SK7, 6SH7, 6SJ7, 6AC7, 6U8A, 6AW8, 6CB6, 6DC6, 6AH6 or 1S5 or 1U5 battery types are used.

Good Luck,

Mike WU2D

[K4QE]

There are some nice designs on the ARRL website:

http://www.arrl.org/tis/info/bldgeqp.html

[c. mac neill w8znx]

Hello OM

tons and tons of information
from 30's Handbooks to Ten Tec Kits

Nor Cal QRP club magazine    QRPP
Vol 7 # 2 Summer 1999
The Regen Receiver issue

nothing but regen receiver projects
all but one are solid state designs

if you can't find a copy
and want one let me know

yours truly

Mac

[WU2D]

Jason,

I fooled with the Morgan Regen and have redrawn it with an output transformer so it can drive low cost low Z headphones. I also incorporated a throttle capacitor for regeneration control which should improve the performance. You can use the 6BF6 or rewire for a 6C4 or you can try a metal 6C5 or 6J5 Octal. All should work well with this. If you need more gain, add another stage. This circuit will work well with batteries - 4 AA in a pack for the fillament and a few 9V batteries in series for the B+.

Mike WU2Dl

[kf6pqt]

Thanks everyone!

Mike, thats the simple design I think I've been looking for. However, something funny happened to your .jpg, do you have a bigger version? Also, whats the info for winding the coils?

Thanks and 73,
Jason kf6pqt

[kf6pqt]

Wait, as in Alfred P Morgan!!!

His ancient books in the library likely had a profound influence on me too, as a little squirt... and this was in the early 80's! Disappointing back then to me that NONE of those parts were available at radio shack.

Found this, too:

http://www.bignick.net/Radio/Radio_1.htm

[WU2D]

Thanks everyone!

Mike, thats the simple design I think I've been looking for. However, something funny happened to your .jpg, do you have a bigger version? Also, whats the info for winding the coils?

Thanks and 73,
Jason kf6pqt

Wow Jason,

You are right - it got messed up. Try these. Here is the original from the book and my mods. Again the 6C4 would be a good choice if you can not find the 6BF6.

Mike WU2D

[kf6pqt]

Thanks!  I've got a pair of 6cb6's that surfaced as I checked a boxfull against the list, so I'll start with those.

73,
Jason kf6pqt

[WU2D]

Hi Jason,

The 6CB6 is a pentode so you have two more grid connections to deal with. This is a way to handle the regeneration with a pentode. A potentiometer is typically put across the B+ supply and the tap is connected to the screen grid. The suppressor grid is tied to the cathode. The screen must be bypassed.

Depending upon the sesitivity of the headphones that you have, you may want to add another audio stage. The Radio Shack transformer does allow simple low-Z (8 to 50 Ohm) headsets to work with the circuit, and the fidelity will be excellent, but the original 2000 Ohm headset will probably provide more volume. The answer is to add an audio stage like a high gain triode (6AV6) or even your other 6CB6 pentode.

One more note on the transformer - it probably will be OK up to 100 VDC of B+, but I would not go higher! That is a transistor circuit transformer.

Mike WU2D

[W1DAN]

Hi:

A couple of years ago Electric Radio had an article on a really nice regen. It looked like the best regen around (not that I have experienced many). I believe it was by Dave Ishmael, WA6VVL.

His page that is promoting an anthology book is here:

http://members.cox.net/daveishmael/VA.htm

Sorry I do not remember more.

73
Dan
W1DAN

[K1MVP]

Jason,
If you do not have a lot of experience building regens,--especially tube
regens,--you might want to order a good book from Lindsay publications,
"How to build your first vacuum tube regenerative receiver" by T.J. Lindsay.
this book has a lot of good info, on different circuit variations, and also
has many "hints and kinks" as to how to build one that is stable, sensitive
and selective.

I have built numerous ones,--and the thing you have to keep in mind ,is
you are basically building an "oscillator", and for stability,--you want a good
"rigid" cabinet for mounting the tuning cap, and all interconnecting components.
A well built regen can give an "all american five" superhet such as an S-38
a "run for its money"

My latest regen project is one that uses an HRO drive and dial, with which
I plan to use a 6c5 or 6c4 as the "heart" of the detector based upon a circuit from Electric Radio,"The Ultimate Regen".

                                   73`s, Rene, K1MVP                             
 

[kf6pqt]

Thanks for the tip! I'm a big fan of the Lindsay books. So far, my smallest order has been like EIGHT books! Its about time to order another load.

-Jason kf6pqt

[W8EJO]

Hi:

A couple of years ago Electric Radio had an article on a really nice regen. It looked like the best regen around (not that I have experienced many). I believe it was by Dave Ishmael, WA6VVL.

73
Dan
W1DAN

Try this link:


http://www.qsl.net/k4axf/regenpage.htm


Terry
W8EJO

[Ed/KB1HYS]

This page has a nice heterodyne type circuit with a Regen detector working on ~2 Mc.

http://www.qsl.net/wd4nka/form.html