Thoughts on a Regen RX?
 

Hi Group, I am entertaining building anohter regen. My first attempt,
although pretty, was a mediocre performer- using a 3 section compactron
tube.
http://parelectronics.com/pics/regen2.jpg
Design goals a
1. plug in coils for band changing MW-20 MHz or so.
2. speaker level audio
3. smooth regen
4. prefer miniature tubes to octal.

Anyone care to post their favorite schematic/ links/ thoughts?

Tnx,

Dale W4OP

Thoughts on a Regen RX?
 

Dale Parfitt wrote:

Hi Group, I am entertaining building anohter regen. My first attempt,
although pretty, was a mediocre performer- using a 3 section compactron
tube.
http://parelectronics.com/pics/regen2.jpg
Design goals a
1. plug in coils for band changing MW-20 MHz or so.
2. speaker level audio
3. smooth regen
4. prefer miniature tubes to octal.

Anyone care to post their favorite schematic/ links/ thoughts?

Tnx,

Dale W4OP


I'm guessing that thats the one from the GE book? I've not built that
one but have heard mixed reviews.
If you really want to build a stable and manageable kick-butter go
regen/superhet. The Regenodyne in its various iterations can be found
on the web and is highly recommended.
I'm just now winding up another revision of the George Grammar rig from
1941 with some added audio stages. I'm tickled (pun) with it! Another
one that is likeable is the ARRL SimpleX Super. I like old stuff and
have thoughts of building it with octals and plug-in coils :)

GL,
Bill

Thoughts on a Regen RX?
 

"- exray -" wrote in message
...
Dale Parfitt wrote:

Hi Group, I am entertaining building anohter regen. My first attempt,
although pretty, was a mediocre performer- using a 3 section compactron
tube.
http://parelectronics.com/pics/regen2.jpg
Design goals a
1. plug in coils for band changing MW-20 MHz or so.
2. speaker level audio
3. smooth regen
4. prefer miniature tubes to octal.

Anyone care to post their favorite schematic/ links/ thoughts?

Tnx,

Dale W4OP
I'm guessing that thats the one from the GE book? I've not built that one
but have heard mixed reviews.
If you really want to build a stable and manageable kick-butter go
regen/superhet. The Regenodyne in its various iterations can be found on
the web and is highly recommended.
I'm just now winding up another revision of the George Grammar rig from
1941 with some added audio stages. I'm tickled (pun) with it! Another
one that is likeable is the ARRL SimpleX Super. I like old stuff and have
thoughts of building it with octals and plug-in coils :)

GL,
Bill

I have a "Science Fair" Regen receiver here which does the AM broadcast band
to 30 mhz. Personally, I think it sucks, but that's my opinion. I acquired
the full manual for it and am contemplating putting it up on E-Bay for
someone who may like Regens to play with. It "may" need the tuning touched
up a bit, but "I" don't have time. It's sat on my shelf for 99.8% of the
time I've owned it.

C.L.F.

Dovetron Product Detector
 

Hi, Gang

I'm thinking of adding a product detector to my HRO-50.
I see that Dovetron used to make an adapter that plugged into
the NBFM socket. Does anyone have any experience
with the Dovetron unit, and can anyone point me
to a schematic? BAMA and the ManualMan came up empty.

Thanks,
Ed Knobloch

Dovetron Product Detector
 

"Edward Knobloch" wrote in message
news:d8fyf.130$C%3.116@trndny03...
Hi, Gang

I'm thinking of adding a product detector to my HRO-50.
I see that Dovetron used to make an adapter that plugged into
the NBFM socket. Does anyone have any experience
with the Dovetron unit, and can anyone point me
to a schematic? BAMA and the ManualMan came up empty.

Thanks,
Ed Knobloch

I have one in a Collins 75A2. It's pretty remarkable.

Thoughts on a Regen RX?
 

A few years ago I had a notion to figure out why most kit regenerative
receivers just didn't work, despite their reputation for great sensitivity,
bla bla bla.

I looked at a few schematics and a few points really jumped out at me.
Basically, most standard Heathkit/KnightKit circuits are just Hartley or
Armstrong oscillators with variable plate or screen voltage, provided by a
potentiometer.. At first this sounds reasonable, but the goal of a
regenerative receiver is really that it NOT oscillate.

Most of the circuits have 2 fatal flaws, both of which lead to the same
result. The 2 flaws are grid-leak bias and resistance coupling to the
following audio stage. The problem is that these techniques cause a shift in
tube operating points as the signal strength changes, making it "snap" into
oscillation. This occurs because any signal, or impulse, or anything else
that drives the grid instantaneously positive causes grid current to flow
and charges the grid capacitor, biasing the grid negative and reducing the
plate current. This wouldn't be so bad except that the reduction in plate
current causes the plate voltage to rise, due to the coupling resistor in
the plate circuit. As the plate voltage increases the gain increases and the
thing snaps into oscillation, ready or not.

I put together a test unit using the Armstrong (tickler) circuit, but I used
NO grid condenser or resistor. Instead, I returned the grid circuit to a
0-20 volt regulated power supply (properly bypassed for RF, of course)so I
could control the grid bias manually. Also used choke coupling, actually the
primary of an output transformer in the plate circuit. Used a 6T4, and the
circuit would still work even with plate voltages below 30 volts.

I didn't fool around with it too much after I proved my point, but the thing
really did work pretty well, far better than any "kit" regenerative I have
ever seen. With regulated power supplies I could get some real sensitivity
and a smooth roll into regeneration. I was impressed. Never did make a real
project of it, but it was a good experiment.

If you go back and look at some of the pre-historic regenerative circuits
you will notice the same concepts at work. Most were choke coupled, and many
used variometers or "throttle condensers" to control regeneration. Again,
these techniques do not allow the DC operating point of the tube to change
with variations in signal strength.

Just food for thought.






"Dale Parfitt" wrote in message
news:Bdeyf.1445$he.1382@trnddc03...
Hi Group, I am entertaining building anohter regen. My first attempt,
although pretty, was a mediocre performer- using a 3 section compactron
tube.
http://parelectronics.com/pics/regen2.jpg
Design goals a
1. plug in coils for band changing MW-20 MHz or so.
2. speaker level audio
3. smooth regen
4. prefer miniature tubes to octal.

Anyone care to post their favorite schematic/ links/ thoughts?

Tnx,

Dale W4OP

Thoughts on a Regen RX?
 

Hi Dale:

I have built a number of regen receivers. One of the great ones is in one
of the "How to Become a Radio Amateur" pamphlets. It was also in QST and
maybe in some of the Handbooks. It uses 2 x 6AQ5 tubes and can run a
speaker directly.

Regeneration is controlled by a pot in the screen and it is very smooth.

Fits all your requirements. If you need more details, I have the bbok
upstairs. I can get the QST date if that helps.

73, Colin K7FM

Thoughts on a Regen RX?
 

"COLIN LAMB" wrote in message
nk.net...
Hi Dale:

I have built a number of regen receivers. One of the great ones is in one
of the "How to Become a Radio Amateur" pamphlets. It was also in QST and
maybe in some of the Handbooks. It uses 2 x 6AQ5 tubes and can run a
speaker directly.

Regeneration is controlled by a pot in the screen and it is very smooth.

Fits all your requirements. If you need more details, I have the bbok
upstairs. I can get the QST date if that helps.

73, Colin K7FM


Hi Colin,
Nice to hear from you- if you have a title, and it made it to the Handbook-
perhaps I have it in one of the vintage ARRL Handbooks- otherwise, date of
the article will be helpful.

Dale

Thoughts on a Regen RX?
 

"COLIN LAMB" wrote in message
nk.net...
Hi Dale:

I have built a number of regen receivers. One of the great ones is in one
of the "How to Become a Radio Amateur" pamphlets. It was also in QST and
maybe in some of the Handbooks. It uses 2 x 6AQ5 tubes and can run a
speaker directly.

Regeneration is controlled by a pot in the screen and it is very smooth.

Fits all your requirements. If you need more details, I have the bbok
upstairs. I can get the QST date if that helps.

73, Colin K7FM


Thanks to the WEB, I have found a restoration article on this RX and a note
giving its original publication.

http://www.antiqueradio.com/Apr01_restoration.html

Dale W4OP

Thoughts on a Regen RX?
 

"Dale Parfitt" wrote in message
news:7Phyf.855$MG1.424@trnddc05...

"COLIN LAMB" wrote in message
nk.net...
Hi Dale:

I have built a number of regen receivers. One of the great ones is in
one of the "How to Become a Radio Amateur" pamphlets. It was also in QST
and maybe in some of the Handbooks. It uses 2 x 6AQ5 tubes and can run a
speaker directly.

Regeneration is controlled by a pot in the screen and it is very smooth.

Fits all your requirements. If you need more details, I have the bbok
upstairs. I can get the QST date if that helps.

73, Colin K7FM


Thanks to the WEB, I have found a restoration article on this RX and a
note giving its original publication.

http://www.antiqueradio.com/Apr01_restoration.html

Dale W4OP

The complete construction article also appeared in the 1964 edition of "How
to Become A Radio Amateur." Don't know if it ever appeared in the Handbook.

I do have a copy of the article, but not handy. If you can wait 10 days or
so I can scan it for you.

Dovetron Product Detector
 

Hi, Dave

Does the Dovetron have a USB/LSB switch,
or can it be switched remotely? (My HRO-50 is rack mounted,
so no easy access through the top of the receiver).
Also, does it provide a good AGC system?
Audio derived AGC? Can you point me to a schematic?

Thanks,
Ed

"Edward Knobloch" wrote in message

I'm thinking of adding a product detector to my HRO-50.
I see that Dovetron used to make an adapter that plugged into
the NBFM socket. Does anyone have any experience
with the Dovetron unit, and can anyone point me
to a schematic? BAMA and the ManualMan came up empty.

Thanks,
Ed Knobloch

Dave Stadt wrote:
I have one in a Collins 75A2. It's pretty remarkable.

Thoughts on a Regen RX?
 

I found the article and will be able to scan it on Monday and send to those
interested. While at it, I will scan the companion transmitter. It uses a
6DQ6 tube, which is plentiful and cheap.

If interested, drop me an e-mail.

73, Colin K7FM

Thoughts on a Regen RX?
 

How about a regenerative superhet? Maybe use a triode/pentode tube as
a converter in front of a regen detector running at 2 or 3 MHz. If you
wanted full coverage the L.O. of the converter would be an LC
oscillator, but for ham-band only you could use a crystal oscillator
for more stability. Might be something like

6EA8 converter (triode oscillator, pentode mixer)
6EA8 detector & first audio (pentode detector w/ screen voltage
control, triode first audio)
6AQ5 or 6CU5 audio out (6CU5 will give more audio at lower B+, 6AQ5
more at higher B+)
OB2 regulator for the 6EA8s

73,
Mike, KK6GM

Thoughts on a Regen RX?
 

The regenerative superhet described by Mike is a good idea. it is known as
the "super gainer" and was pioneered by Frank Jones. They are described in
the 1938 Radio Handbook. The converter in front of the regen receiver
substantially reduces radiation by the receiver and also eliminates the
effect of a swaying antenna. By setting the fixed if between two amateur
bands, both bands can be covered with one oscillator coil. The drawback is
an increase in parts count .

For some, simplicity becomes elegance. There is nothing like honing your
skills during a gusty evening, where the open oscillator coil changes pitch
with each puff of wind and your movement around the room. For those, a
digitally locked oscillator is heresy.

Colin K7FM

Dovetron Product Detector
 

"Edward Knobloch" wrote in message
news:jKiyf.444$Bn4.146@trndny08...
Hi, Dave

Does the Dovetron have a USB/LSB switch,
or can it be switched remotely? (My HRO-50 is rack mounted,
so no easy access through the top of the receiver).
Also, does it provide a good AGC system?
Audio derived AGC? Can you point me to a schematic?

Thanks,
Ed

Extensive AGC mods are part of the change and work very well. USB and LSB
is selected by the variable BFO so no real change there. I can send you
the 75A2/3 instruction and schematic if you wish. Looks like the plug-in is
the same for Collins, HRO and NC-183D. You would be on your own for the
actual radio mods which could be extensive. The plug-in socket gets rewired
as well as numerous other mods.

Thoughts on a Regen RX?
 

Well, copies made today, so I will now scan those. Progress is sometimes
slow. Colin K7FM

Thoughts on a Regen RX?
 

Very smooth regen control. Except for the plug-in coils requirement...

Though I realize the feedback windings would be problematic to reproduce...I
listened to many 40M SSB QSOs on Saturday mornings with the Knight Space
Spanner.


Perhaps LA5KI would consent to doing some measurements on his coils...

73, Steve, K9DCI

http://www.qsl.net/kb7rgg/allied/sch...acespanner.gif
http://www.qsl.net/kb7rgg/allied/pro...dio/83y209.txt

Pix he
http://www.qsl.net/la5ki/org/kn/spsp.htm
It is called a Super-regen here, but I don't think it was.



"Dale Parfitt" wrote in message
news:Bdeyf.1445$he.1382@trnddc03...
Hi Group, I am entertaining building anohter regen. My first attempt,
although pretty, was a mediocre performer- using a 3 section compactron
tube.
http://parelectronics.com/pics/regen2.jpg
Design goals a
1. plug in coils for band changing MW-20 MHz or so.
2. speaker level audio
3. smooth regen
4. prefer miniature tubes to octal.

Anyone care to post their favorite schematic/ links/ thoughts?

Tnx,

Dale W4OP

Thoughts on a Regen RX?
 

I now have the 2 tube regen receiver from "How to Become a RadioAmateur"
scanned and ready to send. Also scanned the companion transmitter. Both
are in .pdf files. Each is about 5 mb. I am just not efficient at
compressing files without losing quality. I will attempt to send them out
to those that have requested. If it fails, we can keep trying.

73, Colin K7FM

Thoughts on a Regen RX?
 

On 1/18/06 8:31 AM, in article
et, "COLIN LAMB"
wrote:

I now have the 2 tube regen receiver from "How to Become a RadioAmateur"
scanned and ready to send. Also scanned the companion transmitter. Both
are in .pdf files. Each is about 5 mb. I am just not efficient at
compressing files without losing quality. I will attempt to send them out
to those that have requested. If it fails, we can keep trying.

73, Colin K7FM



Could you just upload the files to a.b.s.e.? Everyone who wants it can
download it.

Don

Thoughts on a Regen RX? OOPS
 

I compose in Word then paste. This part didn't get pasted:

I had the Knight-Kit Space Spanner and used to listen to some SSB regulars
on 40 M every Saturday.

Very smooth regen control. Except for the plug-in coils requirement...

Though I realize the feedback windings would be problematic to
reproduce...I
listened to many 40M SSB QSOs on Saturday mornings with the Knight Space
Spanner.


Perhaps LA5KI would consent to doing some measurements on his coils...

73, Steve, K9DCI

http://www.qsl.net/kb7rgg/allied/sch...acespanner.gif
http://www.qsl.net/kb7rgg/allied/pro...dio/83y209.txt

Pix he
http://www.qsl.net/la5ki/org/kn/spsp.htm
It is called a Super-regen here, but I don't think it was.



"Dale Parfitt" wrote in message
news:Bdeyf.1445$he.1382@trnddc03...
Hi Group, I am entertaining building anohter regen. My first attempt,
although pretty, was a mediocre performer- using a 3 section compactron
tube.
http://parelectronics.com/pics/regen2.jpg
Design goals a
1. plug in coils for band changing MW-20 MHz or so.
2. speaker level audio
3. smooth regen
4. prefer miniature tubes to octal.

Anyone care to post their favorite schematic/ links/ thoughts?

Tnx,

Dale W4OP