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1994-11-13
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Date: Thu, 25 Aug 94 04:30:27 PDT
From: Ham-Homebrew Mailing List and Newsgroup <ham-homebrew@ucsd.edu>
Errors-To: Ham-Homebrew-Errors@UCSD.Edu
Reply-To: Ham-Homebrew@UCSD.Edu
Precedence: Bulk
Subject: Ham-Homebrew Digest V94 #252
To: Ham-Homebrew
Ham-Homebrew Digest Thu, 25 Aug 94 Volume 94 : Issue 252
Today's Topics:
PC Board design Software
ss delay relay ?
Send Replies or notes for publication to: <Ham-Homebrew@UCSD.Edu>
Send subscription requests to: <Ham-Homebrew-REQUEST@UCSD.Edu>
Problems you can't solve otherwise to brian@ucsd.edu.
Archives of past issues of the Ham-Homebrew Digest are available
(by FTP only) from UCSD.Edu in directory "mailarchives/ham-homebrew".
We trust that readers are intelligent enough to realize that all text
herein consists of personal comments and does not represent the official
policies or positions of any party. Your mileage may vary. So there.
----------------------------------------------------------------------
Date: 23 Aug 1994 20:45:42 -0400
From: america.com!not-for-mail@uunet.uu.net
Subject: PC Board design Software
To: ham-homebrew@ucsd.edu
------------------------------
Date: 24 Aug 94 19:46:52 GMT
From: ihnp4.ucsd.edu!sdcc12!jeeves!daniels@network.ucsd.edu
Subject: ss delay relay ?
To: ham-homebrew@ucsd.edu
I've got an Omnetics Inc. solid-state delay relay that I need
the pin-out for. Part # MMS115A5Y60A, with four spade lugs
numbered 1 - 4. The surplus shop I got it from says it's an
adjustable delay, but I'm pretty sure it's a fixed 60-sec delay.
Does anyone have any information on this part or know the
address/phone # of Omnetics?
Many thanks for any help mark daniels
daniels@jeeves.ucsd.edu
------------------------------
Date: Mon, 22 Aug 1994 13:48:36 GMT
From: agate!howland.reston.ans.net!EU.net!CERN.ch!dxcern!jeroen@ames.arpa
To: ham-homebrew@ucsd.edu
References <32c5hi$mtg@ohlone.kn.PacBell.COM>, <776791198snz@arkas.demon.co.uk>, <fred-mckenzie-1708941430140001@128.159.123.111>
Subject : Re: regenerative sets and selectivity
In article <fred-mckenzie-1708941430140001@128.159.123.111>,
Fred McKenzie <fred-mckenzie@ksc.nasa.gov> wrote:
>The "super-regenerative" receiver (detector) should also be considered in
>the discussion. I never understood how they worked,...
These things have always puzzled me too.
As my current understanding goes, an oscillator tuned to the
approximate frequency of reception is periodically stopped and then
allowed to restart at a rate of, say, 40KHz. If some received
energy at the right frequency is coupled into the resonant
circuit, the restart tends to be quicker, with a noticable effect
on the current drawn by the oscillator.
The current drawn by the oscillator contains the output signal.
Is this how it works?
Best regards,
Jeroen Belleman
------------------------------
Date: Thu, 25 Aug 1994 00:30:45 GMT
From: ihnp4.ucsd.edu!news.cerf.net!mvb.saic.com!MathWorks.Com!europa.eng.gtefsd.com!howland.reston.ans.net!swrinde!sgiblab!ga!kevin@network.ucsd.edu
To: ham-homebrew@ucsd.edu
References <776791198snz@arkas.demon.co.uk>, <fred-mckenzie-1708941430140001@128.159.123.111>, <1994Aug22.134836.8674@dxcern.cern.ch>rinde
Subject : Re: regenerative sets and selectivity
In article <1994Aug22.134836.8674@dxcern.cern.ch> jeroen@dxcern.cern.ch (Jeroen Belleman) writes:
>In article <fred-mckenzie-1708941430140001@128.159.123.111>,
>Fred McKenzie <fred-mckenzie@ksc.nasa.gov> wrote:
>>The "super-regenerative" receiver (detector) should also be considered in
>>the discussion. I never understood how they worked,...
>
>These things have always puzzled me too.
>As my current understanding goes, an oscillator tuned to the
>approximate frequency of reception is periodically stopped and then
>allowed to restart at a rate of, say, 40KHz. If some received
>energy at the right frequency is coupled into the resonant
>circuit, the restart tends to be quicker, with a noticable effect
>on the current drawn by the oscillator.
>
>The current drawn by the oscillator contains the output signal.
>
>Is this how it works?
That is pretty accurate. Usually the circuit can be made to be self quenching
by utilizing the base emitter junction to charge up a suitable time constant
RC network so that the transistor is biased off and oscillation stops.
They are commonly used for garage door opener receivers, burglar alarms
X-10 RF remote control in the 300 MHz range, they can be very simple and
low power but fairly sensitive (1 microvolt).
My first radio control receiver I built 30 years ago used this technology
which was originally developed in the 30's.
They are very broadly tuned, and have a very high noise output on no-signal.
They are also very tricky to design and get going. I find it helps if the
transistor is fairly close to its maximum frequency, otherwise it oscillates
too readily and is not very sensitive.
kevin white
------------------------------
End of Ham-Homebrew Digest V94 #252
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