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Regenerative reciever
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bitrex
Nov 29, 2015, 11:28:37 AM11/29/15
to
I'd like to use one of these junk box 12 volt tubes I have sitting
around to build a regen. I came up with this schematic sitting in
the coffee shop this morning. It's just sort of pieced together
out of various things I've seen over the years.
https://www.dropbox.com/sc/z7qrzqv7lj4h5l7/AACfDZl2fnxKLV5T9p1sH22ea
Trying to inject the detected audio back into the grounded grid RF
stage for amplification. The regen gain stage uses the pentode
section with screen voltage control.
I'm basically trying to use as few coils/variable capacitors as
possible here.
Any suggestions on the design before I rig up this failure? ;)
--
----Android NewsGroup Reader----
http://usenet.sinaapp.com/
bitrex
Nov 29, 2015, 11:31:56 AM11/29/15
to
Cursitor Doom
Nov 29, 2015, 12:08:29 PM11/29/15
to
On Sun, 29 Nov 2015 11:31:41 -0500, bitrex wrote:
> Any suggestions on the design before I rig up this failure? ;)
No suggestions, but full marks to you for having the audacity to recreate
> Any suggestions on the design before I rig up this failure? ;)
this ingenious and much under-rated configuration. Respect!
tabb...@gmail.com
Nov 29, 2015, 12:17:19 PM11/29/15
to
NT
amdx
Nov 29, 2015, 12:38:39 PM11/29/15
to
> http://theradioboard.com/rb/viewforum.php?f=3&sid=40beb155c86578a89750b76f97e578eb
Lots of regen knowledge there.
Mikek
Jan Panteltje
Nov 29, 2015, 1:40:17 PM11/29/15
to
On a sunny day (Sun, 29 Nov 2015 11:28:19 -0500 (EST)) it happened bitrex
No, may even work, even your antenna is isolated from it I think,
so should not radiate that much.
Why the transistor? Current source more gain? Ri of triode is low,
should not help a lot?
so should not radiate that much.
Why the transistor? Current source more gain? Ri of triode is low,
should not help a lot?
bitrex
Nov 29, 2015, 2:29:19 PM11/29/15
to
Jan Panteltje <pNaOnSt...@yahoo.com> Wrote in message:
Active load for the triode
hopefully. High impedance at RF, but
low at audio.
Thought it might be an interesting experiment instead of an RF choke...
hopefully. High impedance at RF, but
low at audio.
Thought it might be an interesting experiment instead of an RF choke...
Jeff Liebermann
Nov 29, 2015, 2:34:19 PM11/29/15
to
On Sun, 29 Nov 2015 11:28:19 -0500 (EST), bitrex
<bit...@de.lete.earthlink.net> wrote:
>Any suggestions on the design before I rig up this failure? ;)
<https://www.dropbox.com/sc/z7qrzqv7lj4h5l7/AACfDZl2fnxKLV5T9p1sH22ea>
<bit...@de.lete.earthlink.net> wrote:
>Any suggestions on the design before I rig up this failure? ;)
What's this transistor thing hanging in the triode plate? If you're
going to do it with a tube, use ONLY tubes. You don't really need the
pentode section in the loop to provide regeneration. It can be done
with just the triode section, leaving the pentode available for audio
amplification. Something like this:
<http://www.junkbox.com/electronics/OneTubeFMReceiverBig.gif>
Some schematics and designs to choose from:
<https://www.google.com/search?q=12ec8+super+regenerative+receiver&tbm=isch>
<http://www.junkbox.com/electronics/lowvoltagetubes.shtml>
<http://theradioboard.com/rb/viewtopic.php?t=6167>
Somewhere in my junk pile is a 45 MHz super-regenerative slope
detecting FM receiver which I build in the 1960's using a 12EC8. It's
one of the few tubes that would work at VHF frequencies with 12V B+
power. It was the prototype of a police motorcycle helmet radio. It
worked, but wasn't quite what they expected. I'll see if I can find
the carcass and schematic.
I don't have an LTspice model for the 12EC8 but this might help build
one:
<https://www.youtube.com/watch?v=fM7qacnRWk8> (5:39)
<http://www.vcu.edu/csbc/bnfo601/Paul_amp_designs/Koren_Tubes.inc>
<http://www.normankoren.com/Audio/Tubemodspice_article.html>
--
Jeff Liebermann je...@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
Rich S
Nov 29, 2015, 4:03:57 PM11/29/15
to
The 'Loose screws' story on his audio page is hilarious.
-RS
Jeff Liebermann
Nov 29, 2015, 5:46:54 PM11/29/15
to
On Sun, 29 Nov 2015 13:03:50 -0800 (PST), Rich S <ri...@engineer.com>
wrote:
>Ha! Norm Koren. A very cool guy (though I'm not a tube-head. We use his Imatest software in the lab).
>The 'Loose screws' story on his audio page is hilarious.
>-RS
<http://www.normankoren.com/Audio/>
I hadn't heard that one before, but knowing the nature of some
audiophiles, I can believe that it's possible. However, from my RF
experiences, "tighten the loose screws" means tighten down the
compression trimmer capacitors,
<https://www.rfparts.com/media/catalog/product/cache/1/image/99a5ad2c495df71db96a88d676e5ff23/4/6/4615_trimmer.jpg>
which wrecks the tuning and alignment. It has happened because I
convinced one of my former friends to do it. Knowing how things
really work is a decided advantage when playing practical jokes.
I'm rather surprised that audiophiles are running SPICE models on
their tube equipment. I've always suspected that they have a fear of
numbers and repeatable tests, preferring instead to use perceptual and
emotional criteria. I demonstrated that long ago with my ambience and
presence meter, and was (temporarily) taken seriously.
wrote:
>Ha! Norm Koren. A very cool guy (though I'm not a tube-head. We use his Imatest software in the lab).
>The 'Loose screws' story on his audio page is hilarious.
>-RS
I hadn't heard that one before, but knowing the nature of some
audiophiles, I can believe that it's possible. However, from my RF
experiences, "tighten the loose screws" means tighten down the
compression trimmer capacitors,
<https://www.rfparts.com/media/catalog/product/cache/1/image/99a5ad2c495df71db96a88d676e5ff23/4/6/4615_trimmer.jpg>
which wrecks the tuning and alignment. It has happened because I
convinced one of my former friends to do it. Knowing how things
really work is a decided advantage when playing practical jokes.
I'm rather surprised that audiophiles are running SPICE models on
their tube equipment. I've always suspected that they have a fear of
numbers and repeatable tests, preferring instead to use perceptual and
emotional criteria. I demonstrated that long ago with my ambience and
presence meter, and was (temporarily) taken seriously.
Tim Wescott
Nov 29, 2015, 9:35:22 PM11/29/15
to
My general impression of regenerative receivers is that because you don't
have many active components, you need to make sure that your passives are
top notch or you get shoddy performance.
I'd go ahead and put a tuned circuit on the antenna side. If you're
using the triode to isolate the antenna from the rest of the rig, I'd use
it as a grounded-grid or grounded-plate amplifier -- either one should
isolate in from out better than what you have.
--
www.wescottdesign.com
Jan Panteltje
Nov 30, 2015, 3:15:48 AM11/30/15
to
On a sunny day (Sun, 29 Nov 2015 14:29:05 -0500 (EST)) it happened bitrex
<bit...@de.lete.earthlink.net> wrote in <emI6y.405683$eJ3.1...@fx10.iad>:
>Jan Panteltje <pNaOnSt...@yahoo.com> Wrote in message:
>> On a sunny day (Sun, 29 Nov 2015 11:28:19 -0500 (EST)) it happened bitrex
>> <bit...@de.lete.earthlink.net> wrote in <NIF6y.202565$sK.9...@fx14.iad>:
>>
>>>
>>>I'd like to use one of these junk box 12 volt tubes I have sitting
>>> around to build a regen. I came up with this schematic sitting in
>>> the coffee shop this morning. It's just sort of pieced together
>>> out of various things I've seen over the years.
>>>
>>>
>>>https://www.dropbox.com/sc/z7qrzqv7lj4h5l7/AACfDZl2fnxKLV5T9p1sH22ea
>>>
>>>Trying to inject the detected audio back into the grounded grid RF
>>> stage for amplification. The regen gain stage uses the pentode
>>> section with screen voltage control.
>>>
>>>I'm basically trying to use as few coils/variable capacitors as
>>> possible here.
>>>
>>>Any suggestions on the design before I rig up this failure? ;)
>>
>> No, may even work, even your antenna is isolated from it I think,
>> so should not radiate that much.
>>
>> Why the transistor? Current source more gain? Ri of triode is low,
>> should not help a lot?
>>
>>
>
>Active load for the triodehopefully. High impedance at RF, but
It is a trimmer no?
I am not familar with that symbol but if it is a cap, it should be really small
else it shorts the antenna input?
<bit...@de.lete.earthlink.net> wrote in <emI6y.405683$eJ3.1...@fx10.iad>:
>Jan Panteltje <pNaOnSt...@yahoo.com> Wrote in message:
>> On a sunny day (Sun, 29 Nov 2015 11:28:19 -0500 (EST)) it happened bitrex
>> <bit...@de.lete.earthlink.net> wrote in <NIF6y.202565$sK.9...@fx14.iad>:
>>
>>>
>>>I'd like to use one of these junk box 12 volt tubes I have sitting
>>> around to build a regen. I came up with this schematic sitting in
>>> the coffee shop this morning. It's just sort of pieced together
>>> out of various things I've seen over the years.
>>>
>>>
>>>https://www.dropbox.com/sc/z7qrzqv7lj4h5l7/AACfDZl2fnxKLV5T9p1sH22ea
>>>
>>>Trying to inject the detected audio back into the grounded grid RF
>>> stage for amplification. The regen gain stage uses the pentode
>>> section with screen voltage control.
>>>
>>>I'm basically trying to use as few coils/variable capacitors as
>>> possible here.
>>>
>>>Any suggestions on the design before I rig up this failure? ;)
>>
>> No, may even work, even your antenna is isolated from it I think,
>> so should not radiate that much.
>>
>> Why the transistor? Current source more gain? Ri of triode is low,
>> should not help a lot?
>>
>>
>
> low at audio.
>
>Thought it might be an interesting experiment instead of an RF choke...
The little trimmer from the cathode of the triode to ground ?
>
>Thought it might be an interesting experiment instead of an RF choke...
It is a trimmer no?
I am not familar with that symbol but if it is a cap, it should be really small
else it shorts the antenna input?
Robert Baer
Nov 30, 2015, 4:46:34 AM11/30/15
to
Robert Baer
Nov 30, 2015, 4:47:12 AM11/30/15
to
bitrex
Nov 30, 2015, 5:07:02 AM11/30/15
to
grounded grid RF amp and grounded cathode audio amp we want that
bypassed for audio frequencies to get more gain, but so the
cathode is not shorted for RF. So probably need an RF choke in
series there...
Jon Elson
Dec 3, 2015, 4:11:07 PM12/3/15
to
Jeff Liebermann wrote:
I demonstrated that long ago with my ambience and
> presence meter, and was (temporarily) taken seriously.
>
Oh boy! I would have loved to be there and observe that demo!
I demonstrated that long ago with my ambience and
> presence meter, and was (temporarily) taken seriously.
>
Some guys I knew used to get "The Abolute Sound" magazine, and were mild
audiophiles. We used to laugh at some of the totally insane stuff in there.
I seem to recall an item by Enid Borbeley about interference coming up the
air hose on her air bearing turntable and corrupting the sound. She
recommended grounding the air hose.
Jon
Jeff Liebermann
Dec 3, 2015, 7:45:26 PM12/3/15
to
On Thu, 03 Dec 2015 15:13:45 -0600, Jon Elson <jme...@wustl.edu>
wrote:
>Jeff Liebermann wrote:
>
> I demonstrated that long ago with my ambience and
>> presence meter, and was (temporarily) taken seriously.
>Oh boy! I would have loved to be there and observe that demo!
The demo was a flop, mostly because nobody was paying attention to the
demo, but instead were arguing with each other over whether ambience
and presence actually existed and was worthy of measuring. The
equipment worked, but experts would have none of it, especially from
students. I think it was about 1968, while I was still in college.
At the time, there was no clear definition of presence. I had read
somewhere that it was the sound quality of an empty room or stage. So,
my meter measured background noise. Essentially, it was a modified
General Radio sound level meter with some extra gain followed by a
differentiator driving a meter amplifier. You could measure the
background noise level on the GR meter, and the degree of change on
the added meter. Incidentally, I still have the original GR sound
level meter buried somewhere. Something like this:
<http://www.radiomuseum.org/r/gener_raco_sound_level_meter_759_b75.html>
I kinda missed with my definition of ambience. I thought it was a
measure of reverberation. I generated a "click" (pulse) and measured
how many returns could be seen on an oscilloscope.
Since then, ambience and presence have been fairly well defined:
<https://en.wikipedia.org/wiki/Ambience_(sound_recording)>
<https://en.wikipedia.org/wiki/Presence_(sound_recording)>
but during my demo, it was akin to witchcraft.
>Some guys I knew used to get "The Abolute Sound" magazine, and were mild
>audiophiles. We used to laugh at some of the totally insane stuff in there.
>I seem to recall an item by Enid Borbeley about interference coming up the
>air hose on her air bearing turntable and corrupting the sound. She
>recommended grounding the air hose.
In early college days, I worked for a h-fi store selling ummm... hi-fi
equipment. I've posted a few anecdotes in the past, so I'll skip the
horror stories. The interesting part of the experience was
discovering how much money was being spent on what I considered
useless home audio devices and components. I had always assumed that
the objective was to produce the best possible sounding music. Nope.
The real objective was to spend more money of the stuff than one's
friends, neighbors, and business associates. The critical moment,
where it all came together, was the next party. The host would show
off his new hi-fi system. Someone would ask what it all costs. The
answer was intended to impress everyone present, who later ran out and
spent even more money on the hi-fi stuff. Like all such pyramid
schemes, eventually one would be expected to run out of money, but I
haven't seen it happen yet.
Fast forward 40+ years, and found myself dealing with one of these:
<http://elanhomesystems.com/gallery_residential.asp>
You don't know what expensive can be until you've seen one of these
smarthome systems. Hi-fi is a big part of the puzzle, but there's
plenty more to help empty the bank account.
wrote:
>Jeff Liebermann wrote:
>
> I demonstrated that long ago with my ambience and
>> presence meter, and was (temporarily) taken seriously.
>Oh boy! I would have loved to be there and observe that demo!
demo, but instead were arguing with each other over whether ambience
and presence actually existed and was worthy of measuring. The
equipment worked, but experts would have none of it, especially from
students. I think it was about 1968, while I was still in college.
At the time, there was no clear definition of presence. I had read
somewhere that it was the sound quality of an empty room or stage. So,
my meter measured background noise. Essentially, it was a modified
General Radio sound level meter with some extra gain followed by a
differentiator driving a meter amplifier. You could measure the
background noise level on the GR meter, and the degree of change on
the added meter. Incidentally, I still have the original GR sound
level meter buried somewhere. Something like this:
<http://www.radiomuseum.org/r/gener_raco_sound_level_meter_759_b75.html>
I kinda missed with my definition of ambience. I thought it was a
measure of reverberation. I generated a "click" (pulse) and measured
how many returns could be seen on an oscilloscope.
Since then, ambience and presence have been fairly well defined:
<https://en.wikipedia.org/wiki/Ambience_(sound_recording)>
<https://en.wikipedia.org/wiki/Presence_(sound_recording)>
but during my demo, it was akin to witchcraft.
>Some guys I knew used to get "The Abolute Sound" magazine, and were mild
>audiophiles. We used to laugh at some of the totally insane stuff in there.
>I seem to recall an item by Enid Borbeley about interference coming up the
>air hose on her air bearing turntable and corrupting the sound. She
>recommended grounding the air hose.
equipment. I've posted a few anecdotes in the past, so I'll skip the
horror stories. The interesting part of the experience was
discovering how much money was being spent on what I considered
useless home audio devices and components. I had always assumed that
the objective was to produce the best possible sounding music. Nope.
The real objective was to spend more money of the stuff than one's
friends, neighbors, and business associates. The critical moment,
where it all came together, was the next party. The host would show
off his new hi-fi system. Someone would ask what it all costs. The
answer was intended to impress everyone present, who later ran out and
spent even more money on the hi-fi stuff. Like all such pyramid
schemes, eventually one would be expected to run out of money, but I
haven't seen it happen yet.
Fast forward 40+ years, and found myself dealing with one of these:
<http://elanhomesystems.com/gallery_residential.asp>
You don't know what expensive can be until you've seen one of these
smarthome systems. Hi-fi is a big part of the puzzle, but there's
plenty more to help empty the bank account.
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