QRZ! Ham Radio 4/QRZ Ham Radio Callsign Database - Volume 4.iso/digests/equip/940109.txt

Internet Message Format | 1994-11-14 | 10KB

Date: Fri, 15 Apr 94 04:30:20 PDT
From: Ham-Equip Mailing List and Newsgroup <[e-mail]>
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Subject: Ham-Equip Digest V94 #109
To: Ham-Equip


Ham-Equip Digest            Fri, 15 Apr 94       Volume 94 : Issue  109

Today's Topics:
                   *** FM RECIEVER HELP/ADVICE ***
         Looking for info on new Radio Shack DSP audio filter
                            Mobial Radios
                              Why is it?

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Problems you can't solve otherwise to [e-mail].

Archives of past issues of the Ham-Equip Digest are available
(by FTP only) from UCSD.Edu in directory "mailarchives/ham-equip".

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: Thu, 14 Apr 1994 09:56:39 GMT
From: ihnp4.ucsd.edu!agate!howland.reston.ans.net!europa.eng.gtefsd.com!emory!rsiatl!ke4zv![e-mail]
Subject: *** FM RECIEVER HELP/ADVICE ***
To: [e-mail]

In article <[e-mail]> [e-mail] (NAME = "Andy") writes:
>
>I want to build a reciever to work in the high VHF range ~160Mhz, for
>transmitting digital data, I am considering using IC's because space is a
>premium. I am looking at using a Motorola MC3362 narrowband FM reciever. In the
>many books I have been reading they suggest using a phased lock loop and/or?
>duel modulas prescalers for circuits to work at high frequencies. The problem
>is that I don't understand what the PLL and prescler are supposed to do and
>I don't understand how they work. The PLL seems to allow multiple channels but
>that is not a requirement, does it offer superior frequency stability?

If you're only interested in one frequency, just use a single crystal.
The PLL is for frequency agility. Don't bother with LC tanks, too unstable
at VHF.

>The MC3362 also has two inputs to the first mixer, some example circuits use
>both inputs using a transformer for impedence matching, other examples
>use only one input (other input grouded) and inductors for impedence matching,
>whats the advantage of using the two inputs Vs one input to the first mixer?

It depends entirely on the circuit in front of the chip. If its a balanced
circuit, as in some filter networks, then feed it balanced. If, as is more
likely, its an unbalanced network, then connect it unbalanced.

Gary
--
Gary Coffman KE4ZV          |    You make it,     | gatech!wa4mei!ke4zv!gary
Destructive Testing Systems |    we break it.     | uunet!rsiatl!ke4zv!gary
534 Shannon Way             |    Guaranteed!      | emory!kd4nc!ke4zv!gary
Lawrenceville, GA 30244     |                     |

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Date: 14 Apr 1994 19:00:19 GMT
From: library.ucla.edu!europa.eng.gtefsd.com!news.umbc.edu!eff!news.kei.com!yeshua.marcam.com!zip.eecs.umich.edu!newsxfer.itd.umich.edu!news1.oakland.edu!vela.acs.oakland.edu!@ihnp4.ucsd.edu
Subject: Looking for info on new Radio Shack DSP audio filter
To: [e-mail]

Gee Val,

I wish *I* got some of the commision on these DSP units just from all
the folks in the USECA club that have bought them in the past week!

By the way, I gave a live demo of the unit on the USECA repeater last
night and followed it with a second demo during the Michigan QRP Club 2M
FM net.  Very impressive.

73 =paul= wb8zjl

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Date: Thu, 14 Apr 1994 17:23:21 GMT
From: ihnp4.ucsd.edu!library.ucla.edu!europa.eng.gtefsd.com!news.umbc.edu!eff!news.kei.com!yeshua.marcam.com!siemens![e-mail]
Subject: Mobial Radios
To: [e-mail]

Hi

I am looking to by a new mobile FM radio for 2M and 440.  I am
looking at the Kenwoods  TM 741 (742), TM 732 (733).  I would like to know
what you think of these two radios?

- Are their any known problems with either of them?

- How reliable are they?

- How easy is it to put a third band in the 741?

- How easy is it to remote the control heads on these radios?

Also if you think anohter brand might be better please let me
know.

Thanks very much for your help


Dave Post
WA2QIK
[e-mail]
Princeton, NJ

PS  Please forword your comments directly to me, thanks.

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Date: 14 Apr 94 15:19:08
From: usc!howland.reston.ans.net!europa.eng.gtefsd.com!news.umbc.edu!eff!news.kei.com!yeshua.marcam.com!zip.eecs.umich.edu!newsxfer.itd.umich.edu!news1.oakland.edu![e-mail]
Subject: Why is it?
To: [e-mail]

In article <[e-mail]> [e-mail] (Gary Coffman) writes:

   The better ham is the one who more effectively communicates with whatever
   equipment he has. That's what radio is about, communication.
<balance of excellent post deleted>

Gary went on to explain levels of abstraction as "building blocks for
communications systems" and that they are all valid levels for amateur
communications operation and experimentation.  He enjoined us to see the
larger picture.  "That larger picture is to effectively transfer
information from location to location via EM radiation."

I don't normally go on so, but it really addresses the major portion
of the homebrew/appliance,  CW/digital/voice,  contest/QSO... kinds of
flamewars.  Everyone can see at least one "tree" in the "forest".  Some
think it's the only "real" tree.  Some folks can see much more of the
forest and can appreciate their various and singular beauty.

I wish I had said it as well.
--
Val Breault - N8OEF - [e-mail]   \      /|
Instrumentation dept  GM NAO R&D Center   \    / |
My opinions are not necessarily those of   \  /__|
GMR nor of the General Motors Corporation   \/   |___

------------------------------

Date: Thu, 14 Apr 1994 20:02:54 GMT
From: ihnp4.ucsd.edu!library.ucla.edu!europa.eng.gtefsd.com!news.umbc.edu!eff!news.kei.com!world![e-mail]
To: [e-mail]

References <[e-mail]>, <[e-mail]>, <[e-mail]>p
Subject : Re: Adding 1750 Htz tone to HT

In <[e-mail]> NADO000 <[e-mail]> writes:

>Do give us this info please, although it turns out that with some
>rigs, it is just a matter of knowing which jumper to cut... And
>Alinco does not want to tell us which one it is. They want $50 to do
>it, which is a bit of a ripp-off, in my opinion.

I looked at the schematic for a friends's Alinco Dual-Bander because I
needed a dual-bander and 1750 toneburst for my UK trips.

It turned out that this Alinco replaced the DTMF board with the 1750 tone
burst board on European models.

I wrote an article back in 1991 that made it's way into info-hams (and also
the QRZ disk) that tells how to add tone burst to a ICOM 24AT (It's two
surface mount resistors added for the audio path and removing a diode for
configuration). I ended up with a W2A which looks like it is 5 components
and diode configuration change, but I have not tried it yet.

I would suggest that if there is tone circuitry on the board, then there
very well might be a configuration jumper to cut.

73 Eric   [e-mail]

------------------------------

Date: 14 Apr 94 16:21:45 EDT
From: ihnp4.ucsd.edu!swrinde!gatech!udel!pacs.sunbelt.net![e-mail]
To: [e-mail]

References <[e-mail]>, <[e-mail]>, <[e-mail]>,<[e-mail]>∙
Reply-To : [e-mail]
Subject : Re: I passed my tests-now what?

In article <[e-mail]>, [e-mail] (hamilton on BIX) writes:
>[e-mail] (Roger Keating) writes:
>
>>Doug Hamilton's description of how he picked his first new rig was fun
>>to read.  Doug, now what do you like more about the hobby, shopping for
>>the rig, or actually using it?
>
>I'm glad you enjoyed my comments.  I hope they were useful to others faced
>with trying to decide how to decide on a radio.
>
>As you guessed, shopping for the rig and actually using are BOTH fun.
>Right now, since I'm still waiting for the FCC to mail me the license
>(9 weeks and counting after taking the exams) so I'm still just
>listening.  But that's fun.  I'm intent upon developing my CW ability
>so I'm copying any signals I can, just plugging along.  It'll only
>get better once I can try actually participating.
>
>Thanks for your comments!
>
>Regards,
>Doug Hamilton   [e-mail]   Ph 508-358-5715
>Hamilton Laboratories, 13 Old Farm Road, Wayland, MA  01778-3117


As you look for a "first rig," don't forget hamfests...there are lots of
good "older" rigs out there...and at the hamfests you can talk with hams who
have actually used the rig and know how it performs.  After saving my
pennies, I bought a Yaesu Ft101-E (circa late 1970's??) about 6 weeks
ago, and it is working great.  Came in under budget, even considering
the purchase of antenna wire, cable, books, etc.  So, as many of the
other writers have commented, don't get "wowed" by the glitzy ads in
the magazines and don't think you have to have all the bells and
whistles on your first rig.  I am a "re-tread" ham - was licensed
in the 1960's BST (before solid state) - and have re-activated since
1987.  Lots of differences...lots of improvements...but I think there
is a dependency on high-tech stuff that might get in the way of the
simplicity of making contacts sometimes...and it is  certainly
MUCH more expensive than the old, simple gear.  Hope this helps.  C.U> on
the bands.

73

N4QIX

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End of Ham-Equip Digest V94 #109
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