Date: Wed, 15 Dec 93 04:30:34 PST
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Subject: Ham-Equip Digest V93 #134
To: Ham-Equip
Ham-Equip Digest Wed, 15 Dec 93 Volume 93 : Issue 134
Today's Topics:
For Sale
Looking for Mods for DJ-580t
pagers
Receiver sensitivity (2 msgs)
Signal/One CX7A help
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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.
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Date: 13 Dec 1993 14:03:54 GMT
From: olivea!pagesat!news.cerf.net!lsi.lsil.com!plf10!willis@uunet.uu.net
Subject: For Sale
To: ham-equip@ucsd.edu
Keywords:
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Date: Mon, 13 Dec 1993 04:48:12 GMT
From: saimiri.primate.wisc.edu!caen!malgudi.oar.net!mercury.wright.edu!alpha!gsmith@ames.arpa
Subject: Looking for Mods for DJ-580t
To: ham-equip@ucsd.edu
Hello:
I am looking for mods for my DJ-580t. I already know about the
red wire/blue wires. And the speeddialer speed increase. Does anybody
know any other mods, I am collecting them. I am interested in anything
you can come up with, let me know. Thanks
-73-De Greg, N8PPZ
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Date: 12 Dec 1993 19:15:27 -0700
From: agate!howland.reston.ans.net!sol.ctr.columbia.edu!news.kei.com!news.byu.edu!cwis.isu.edu!u.cc.utah.edu!not-for-mail@ames.arpa
Subject: pagers
To: ham-equip@ucsd.edu
I am looking for a pager that is in the 454Mhz region. As amatuer
operators, I thought that someone would know where I could pick up a pager
at a reasonable price, used or new. The one I am looking to get cost
around $110.00. They are the Motorola series.
Any help would be helpful
TNX
Christian Nielsen
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Date: Mon, 13 Dec 93 12:53:11 GMT
From: library.ucla.edu!europa.eng.gtefsd.com!howland.reston.ans.net!vixen.cso.uiuc.edu!sdd.hp.com!nigel.msen.com!yale.edu!newsserver.jvnc.net!a3bee2.radnet.com!cyphyn!randy@network.ucsd.edu
Subject: Receiver sensitivity
To: ham-equip@ucsd.edu
I hate to say this... but, being 1993, with everyone using High power,
(both Ham and commercial alike) and noise made by appliances... any
receiver with better than 10 u-volt sens is a waste:
All you do is push the S-meter (if any) up higher with the background
noises...
IMD is more likly, unless you spend $2000 $6000 for a rig with all the
stuff to cure such problems
You end up hearing people who'll never hear you back!
The only people who'd really benifi from such o.1 u-volt rated sets , would
be those who live well away from all other radio emitting devices, and someone
into moon-bounce (or swling voyager maybe) is who'd notice/ appreciate it.
I would say, don't worry about the sens...worry about how well the set will
react to IMD condx and related problems.
As to my self, with the 'un-sensitive' rx set I have, I hear anyone who'd
hear me, and can hear the background noise of the air.
My set was tested to be 11u-volts S/s-n...( 11u-v to produce a hearable sound)
--
Randy KA1UNW If you get a shock while
servicing your equipment, "Works for me!"
randy@192.153.4.200 DON'T JUMP! -Peter Keyes
You might break an expensive tube!
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Date: 11 Dec 93 11:04:10 GMT
From: noc.near.net!news.delphi.com!BIX.com!arog@uunet.uu.net
Subject: receiver sensitivity
To: ham-equip@ucsd.edu
gganderson@augustana.edu (Kevin Anderson -7325) writes:
>I know in general one wants a receiver with a low sensitivity
>threshold in terms of lower microvolts.
>Is there a practical way I can understand the differences between
>receivers of say 2, 1, .5, and .125 microvolts sensitivity?
>Obviously the factors of power of transmitted signal, distance
>to source, interference, etc., all play into this. But is there
>really an effective minimum sensitivity one needs for say local
>VHF repeater/simplex use versus "general" HF versus DX HF?
>How do broadcast AM, FM, TV and international SW stations compare
>to amateur signals in field strength and required receiver
>sensitivity?
>Thanks. 73 de Kevin
>* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
>Kevin L. Anderson, Geography Dept., Augustana College
>Rock Island, Illinois 61201 USA phone: (309) 794-7325
>e-mail: gganderson@augustana.edu or kla@helios.augustana.edu
>* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
There is a critical element that you left out: Bandwidth.
The wider the passband of the reciever, the more noise is
present. This is the major difference between land mobile
and amateur recievers v those for FM broadcast. It is this
noise that the signal must overcome in the limiters, so a
proper sensitivity description is 1 uv for 12 db sinad.
The begining of there being a usable signal is where the
shot noise (popcorn) has just been suppresed. For that
1 uv example, that might be somewhere between .5 and .7
uv from the sig generator.
One limit is sensitivity is that a really.hot reciever
is also more likely to suffer from front end overload
from strong off channels signals, such as someone like
me in the next car over when I ran a 90 watt Motrac on
two meters or now where I run a 70 watt Micor on UHF.
-------------------------------
Alan Ogden, w6spk
arog@BIX.com, moderator of ham.radio
------------------------------
Date: 13 Dec 1993 14:03:05 GMT
From: ucsnews!sol.ctr.columbia.edu!howland.reston.ans.net!usenet.ins.cwru.edu!nigel.msen.com!ilium!gdls.com!usenet@network.ucsd.edu
Subject: Signal/One CX7A help
To: ham-equip@ucsd.edu
I too purchased a Signal 1 at Dayton several years ago after talking to a few
friends about theirs. I spent big bucks getting it repaired/modified and it was
worth every cent. It is a truly marvelous radio to use (especially on CW),
although it was designed for SSB. I have yet to find a radio that can compare
to it on CW (IMHO).
There are two "experts" who repair these radios - Mark Mandelkern in NM and
Paul Kollar here in Detroit. Paul knows just about everyone who owns one, and
the complete history of them as he was the repair source for Payne in Nashville
(the original only dealer).
I have all the SIgnal 1 newsletters and a ton of other correspondence. One should
note that many of the modifications in the newsletters are incorrect or contradictory.
Paul Kollar has come up with a list of (at last count) 125 mods that are needed, or
suggested. Included is a mod for a new audio amp.
If there is interest, I may be able to post the mod list.
I would love to correspond with owners and interested parties. Perhaps a mailing list?
73's
Bill
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End of Ham-Equip Digest V93 #134
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