HDTenEightyP/NetNews huggingface dataset:
From: vbreault@rinhp750.gmr.com (Val Breault)
Newsgroups: rec.radio.cb
Subject: Re: setting up a radio...
Date: 13 Oct 92 15:48:31 GMT
Article-I.D.: rinhp750.VBREAULT.92Oct13114832
Distribution: usa
Organization: General Motors Research Labs
In-reply-to: darrellm@pogo.wv.tek.com's message of 12 Oct 92 18:48:31 GMT

In article <13745@pogo.wv.tek.com> darrellm@pogo.wv.tek.com (Darrell McGinnis) writes:

	   Hi, all...
Howdy.
	   I want to fire up my CB again. I'll be running a
	   homebrew vertical (coxail) dipole fed with ~90 ft
	   of mini-8 type of coax.
A little lossy, but not bad

	   I'll be matching the antenna with a (gamma?)-matching length
	   of other coax.
Once pruned to resonance I don't think that a matching network would
be necessary.  The characteristic impedence may be a little high, but
not by a significant amount.

	   How can I minimize phone/tv RFI problems.
(1) Clean signal, (2) Legal power, (3) Antenna far from phone lines & TV ant.

	   I can buy a Lowpass filter BOOO! HISSS! or what?
$ure you can. It's a good way to assure (1) above.

	   I've seen ARRL discuss coiling 6-8 turns of coax into a loop,
	   does this work as  low-pass ? Whats apropriate to 27MHz ?
It's a choke balun.  It's a high impedence to RF on the outside of
the coax.  It helps prevent the coax from radiating.

	   Also, my radio is an older royce with built-in swr, How can I
  	   calibrate this meter before I use it ?
Best guess would be to assume it's only good for relative measurements.
(ie:  Just use it to observe trends, not absolute values)

	   I tried a 50ohm resistor (5watt) but couldn't get the meter
	   to adjust to 1:1.
Hmmm... If it was a wire wound resistor it probably had a lot of inductance.

	   Do I need a special RF dummy-load  to get a reasonable reading ?
Radio Shack sells low power dummy loads that would suit your needs quite well.

	   If I can't get a good SWR reading should I go for a PI tuning
	   network between the radio & the feed line ? & adjust to the 
	   minimum achieveable ?
Sure, you can build a matching network.  You can buy a matching network
(with built in power/SWR meter) at any amateur radio supply store.  Best
bet though is to concentrate on tuning the antenna.

	   How can I verify the impedance of the antenna system ? 
SWR is *ONE* measure of antenna system "goodness".  It's not the whole
thing, but a relative SWR indicator is already built into your rig.

	   thanks...
Welcome...

-val-

--

Val Breault - vbreault@gmr.com - N8OEF
General Motors Research and Environmental Staff.
The opinions expressed by the author do not necessarily reflect 
those of the GMRES or the General Motors Corporation.
 
Newsgroups: rec.radio.cb
From: jbs@rti.rti.org
Subject: Re: Linear Amps..
Organization: Joe's Bar and Grill
Distribution: usa
Date: Thu, 8 Oct 92 21:02:21 GMT

In article <randall.718564164@seashore> randall@informix.com (Randall Rhea) writes:
>
>>This is a common misconception about skip communications. Back in my
>>younger days, I did plenty of CB skip communications using a mobile
>>AM tranceiver that was unmodified. It had about 3 watts out. 
>>All extra power does is make your signal a little clearer - on the
>>other end. 
>
>I'm not sure when your "younger days" were.  Today, when the
>band is open (i.e. when skip conditions exist), the 500W monster
>stations dominate and cause tremendous interference.   There is
>little or no way for a 3W AM transmitter to get through the
>noise and QRM.  Theoretically, if the channel is empty, you
>can certainly "work skip" with 3W AM.  Such ideal conditions
>almost never exist, however.

You just haven't been staying up late enough.

A year or so ago, when I was up pretty much every night until about 2 a.m.
ragchewing with the locals, short band openings were actually not at all
uncommon in the middle of the night. I talked to many, many people on the
other side of the country on 4W AM with no trouble at all, and with signal
reports of anywhere from 3 to 7 S-units at the other end. These openings
typically lasted an hour or less, but there was one memorable night when
the band opened up at 11:30 and stayed really hot until I went to sleep
around 3:00. I logged around 20 DX contacts that night.

Once during one of these openings I plugged up my TRC-217(?) walkie-talkie
to the coax leading to the A-99 (atop a pine tree), and continued a QSO on
low power (about one watt).

What makes this work is that the linear jockeys get tired of talking to
themselves after the skip dies out in the early evening, and they go find
something else to do, leaving the really choice band openings to us QRP
folk.

   -joe
Newsgroups: rec.radio.cb
From: johnw@bluemoon.rn.com (John L. Wilkerson Jr.)
Subject: Re: Linear Amplifiers
Organization: Blue Moon BBS ((614) 868-998[024])
Date: Sat, 10 Oct 92 17:33:20 EDT

odonnell@ocf.berkeley.edu (Shawn Christopher O'Donnell) writes:

> 
> Obviously I'm not posting this simply to announce that I will build a
> linear for myself, I am writing because I want other opinions on
> how to accomplish what I want without having to spend a weekend
> buiding something that is illegal in the first place, and might not
> even work in the second: some people have said that increasing 
> the power from 4W to 60W will only make a small difference, if any
> at all. What's that all about? Why doesn't more power on a given
> settup translate into commensurately greater range on the same settup? 
 
     That is a common misconception that MOST linear jockeys seem to 
believe.  They figure twice the legal power gives 'em twice the range and 
so forth.  Wrong!   I'm sure someone else will give you the proper stats 
on that, as I don't have 'em.   Radio don't work like that.  A good 
antenna, mounted good enough would increase range better than an 
amplifier.
 
> 
> Basically, I want to be heard clearly within a 30 mile radius under
> bad conditions. I was planning to build a Linear with variable
> output that would do from 4W on the low side to 150W on the high side.
> I figure, that will be enough for my purposes, and if its too much, I can
> always turn it down. On the other hand, I truly don't want to be
> an irresponsible person and if there is a "right" way to do the same thing
> that is somehow more sensitive to the insensitive people that surround me,
> I would definitely like to know what it is.
> 
    This invalidates the above which sez you aren't indicating you'll 
build it yourself.... gotcha.
     Plus there is /no/ responsible way to use a linear.  As soon as you 
would turn it on, you would become one of those "insensitive" people.
 
   BUT.... I do sympathize with you.  Living in the Big City myself I 
know what you are going through.... probably LESS, as Columbus, OH is a 
lot smaller than LA.

--
  ___                      _       _     __  _
 (   >      /            _//      ' )   /   // /
  __/______/_  ____      /         / / / o // /_  _  __  _   ________
 / /  (_) / /_/ / <_    /___ o    (_(_/ <_</_/ <_</_/ (_/_)_(_) / / <_
<_/     johnw@bluemoon.use.com     jwilkerson@delphi.com
        71140.77@compuserve.com
From: john.denison@yob.sccsi.com (John Denison)
Newsgroups: rec.radio.cb
Subject: LINEAR AMPLIFIERS
Date: 12 Oct 92 12:44:00 GMT
Article-I.D.: yob.519.334.uupcb
Reply-To: john.denison@yob.sccsi.com (John Denison)
Distribution: world
Organization: Ye Olde Bailey BBS - Houston, TX - 713-520-1569

-> criticize me for running a "baby unit" that "only" runs 4W. The Los
-> Angeles area, where I live, seems sufficiently noisy during the day
-> that 4W just is not enough. Furthermore, I haven't seen or met anyone

If you really need to get out then try using a more efficient antenna,
or if your radio is always kept at home then try a base antenna. Most of
the locals I hear use 4 watts with base antenna like the Antron 99 and
they don't need more power. I'm in Houston so I know what it is like in
a big city, but most of what is heard during the day time isn't local
and most isn't unavoidable. Most of the locals around here come on about
9 pm when the skip dies down.
                                                                                            
Newsgroups: rec.radio.cb
From: Kirk.Smith@bbs.oit.unc.edu (Kirk Smith)
Subject: Re: Continuous Tone Signaling on CB
Keywords: CB, CTSS, selective calling, tone actuated squelch, Part 95
Organization: Extended Bulletin Board Service
Distribution: usa
Date: Fri, 9 Oct 1992 17:16:28 GMT

I've got a boxfull of selective call encoders/decoders made by SBE that
I picked up in a radio deal.  I sold the radios (they were VHF-Lo), hand
still have the encoder/decoders.  They were apparently designed for CB,
as they have manuals which talk about how to hook them up.  They
connect to the speaker and microphone in/outs of the CB.  If anyone is
interested in them, I'll sell them.  Send me email for more info.  I'll
dig out a manual and tell you more about them.  

-Kirk

--
   The opinions expressed are not necessarily those of the University of
     North Carolina at Chapel Hill, the Campus Office for Information
        Technology, or the Experimental Bulletin Board Service.
           internet:  bbs.oit.unc.edu or 152.2.22.80
From: vbreault@rinhp750.gmr.com (Val Breault)
Newsgroups: rec.radio.cb
Subject: Re: CB Tips
Date: 8 Oct 92 14:10:08 GMT
	<1992Oct7.181704.20015@hpcvaac.cv.hp.com>
	<1992Oct8.025412.24699@ke4zv.uucp>
Organization: General Motors Research Labs
In-reply-to: gary@ke4zv.uucp's message of 8 Oct 92 02:54:12 GMT

In article <1992Oct8.025412.24699@ke4zv.uucp> gary@ke4zv.uucp (Gary Coffman) writes:
   In article <1992Oct7.181704.20015@hpcvaac.cv.hp.com> billn@hpcvaac.cv.hp.com (bill nelson) writes:
   >taber@ultnix.mro1.dec.com (Patrick St. Joseph Teahan Taber) writes:
   >: 
   >: Bzzzzzzzt!  Sorry, but we'll give you a copy of our home game for playing.
   >: 
   >: It *is* illegal to posess a CB amp.
   >
   >It is? Then why have hams modified them for use on the 10M band?
   >
   >Why, when the FCC was enforcing 11M regs better, did they not confiscate
   >linears that were not connected to the transceiver and antenna?
   >
   >I think you will find that it is illegal to sell them to the general public
   >but that simple possession is not illegal.

   It has been illegal to *possess*, use, or sell a non-type accepted
   amplifier capable of operation below 144 MHz since April 28, 1978.
   There are two exceptions to this rule. 1) Equipment manufactured
   before the cutoff date is exempt. 2) Licensed radio amateurs may
   build or modify one external power amplifier for use in this
   frequency range without type acceptance in any calendar year.
   This is spelled out in Part 95.509 of the Citizen's Radio Service
   rules and in Part 97.76 and 97.77 of the Amateur Service rules.
   Type accepted equipment operating in this frequency range, must
   be *permanently damaged* by attempts to operate in the Citizen's
   Band in order to qualify for type acceptance, from 97.77.

   Gary KE4ZV

Thanks Gary and (in another post) John for taking the time to look
up the references.  I promised to do it last night but didn't find
the time.  I'm glad that you gentlemen raised the discussion from
opinion to fact.  This information is not in the FAQ.  Perhaps it
ought to be.

-val-

--

Val Breault - vbreault@gmr.com - N8OEF
General Motors Research and Environmental Staff.
The opinions expressed by the author do not necessarily reflect 
those of the GMRES or the General Motors Corporation.
 

Newsgroups: rec.radio.cb
From: johnw@bluemoon.rn.com (John L. Wilkerson Jr.)
Subject: RE: COBRA HT
Organization: Blue Moon BBS ((614) 868-998[024])
Date: Thu, 15 Oct 92 05:04:16 EDT

john.denison@yob.sccsi.com (John Denison)  writes:

> 
> night. I'm wondering if the Cobra HT will use RS's speaker mic since it
> has a mic jack and earphone jack close to each other like one of RS's
> walkie talkies. The Wal-Mart price was $88.95 plus tax.
>                                                                              

     That is a standard speaker mic jack, so my bet is yes, it will work.  
I use one with my Radio Shack Handheld (the new one that allows such a 
mic) and it sounds good for a handheld speaker.  I haven't talked to 
anyone yet, so I cannot tell you how good it "talks"
 

--
  ___                      _       _     __  _
 (   >      /            _//      ' )   /   // /
  __/______/_  ____      /         / / / o // /_  _  __  _   ________
 / /  (_) / /_/ / <_    /___ o    (_(_/ <_</_/ <_</_/ (_/_)_(_) / / <_
<_/     johnw@bluemoon.use.com     jwilkerson@delphi.com
        71140.77@compuserve.com
From: system@gravebbs.UUCP (SYSTEM 0PERATOR)
Newsgroups: rec.radio.cb
Subject: Antenna Mounting...
Date: Mon, 12 Oct 92 10:07:18 PDT
Organization: The Graveyard BBS, CA  [408] 683-4606

Just to briefly get off the topic of LINEAR AMPS..  I bought a 108" steel 
whip and I was planning to mount it onto my roof.  But:
1. Where's the best place to mount it?  (Chinmey, Edge, Gutter?)
2. Is it necessary that I ground it?
3. Does the cable really matter?  (Does it HAVE to be RG-58 or RG-8?)

Thanks.

---
system@Hotcity.Com!gravebbs.UUCP (SYSTEM 0PERATOR)
Graveyard BBS +1 [408] 683 - 4606
[Waffle 1.65]
(19200 Telebit PEP) (2400/MNP)
Newsgroups: rec.radio.cb
From: billn@hpcvaac.cv.hp.com (bill nelson)
Subject: Re: CB Tips
Organization: Hewlett-Packard Company, Corvallis, Oregon USA
Date: Thu, 8 Oct 1992 18:48:12 GMT

vbreault@rinhp750.gmr.com (Val Breault) writes:
: 
: Thanks Gary and (in another post) John for taking the time to look
: up the references.  I promised to do it last night but didn't find
: the time.  I'm glad that you gentlemen raised the discussion from
: opinion to fact.  This information is not in the FAQ.  Perhaps it
: ought to be.
: 

I thank them for listing the references also. However, I will have to
hunt them up and read them myself before I become convinced. I have
seen nothing that prohibits simple possession.

Use on 11 meters is prohibited, as it should be. That is not the point.
Note that the information quoted by John does not say anything about
possession being illegal. It says that the FCC will presume that you
have used the linear on 11 meters if you both posses a linear and there
is other evidence that you have used it.

Bill
From: larson@loren.net.com (Alan Larson)
Newsgroups: rec.radio.cb
Subject: Re: Linear Amps..
Date: 9 Oct 92 00:25:06 GMT
Distribution: usa
Organization: none

In article <1992Oct8.200330.6141@hpcvaac.cv.hp.com> billn@hpcvaac.cv.hp.com (bill nelson) writes:

>The major advantage of SSB over AM is the almost complete elimination
>of heterodynes due to the carriers being suppressed. A secondary advantage
>is the reduced bandwidth - resulting in less noise pickup.

>The additional 3+ db of signal strength does not gain all that much.

  Actually, it is more like 7.8 dB signal strength, assuming you
put the same total power to the antenna.

  Here is why:  With a 4 watt carrier, 100 percent modulation would
add 2 watts of sideband energy, split between the two sidebands.
The upper sideband would have 1/2 of that, or one watt.  This is
1/6 of the total power (7.78 dB).

  This energy is spread over twice the bandwidth of the SSB signal,
so there is a 3 dB difference in noise floor, if dealing with noise.
This, combined with the above, can give a 10.7 dB advantage to SSB.

  AM has a threshold effect, sort of like FM, of about 10 dB,
so there is also that effect as well of minimum signal levels.
As a result of this, by the time the AM signal will be detectable,
the SSB signal will be easy copy.

  Now, in fact, if the band is open, none of this is likely to
matter, since the signal levels will be good enough that AM should
work fine.

	Alan
Newsgroups: rec.radio.cb
From: billn@hpcvaac.cv.hp.com (bill nelson)
Subject: Re: Talking Skip, was Re: Linear Amps..
Organization: Hewlett-Packard Company, Corvallis, Oregon USA
Date: Thu, 8 Oct 1992 18:58:14 GMT

petesk@microsoft.com (Pete Skelly) writes:
: All this talk about how Linears are illegal, etc, as well as other
: illegal activities has moved to talking skip.  Now, as I am a amateur
: radio operator, I was never really interested in skip on CB.  However,
: I seem to remeber that there was something about not communicating
: over 20 (or was it 30) miles away.  This was in the CB regulations
: somewhere.  Now, am I making a fool of myself 'cause I misread the
: rules, or because they remanded that rule, or is talking skip illegal.

If I recall correctly, the distance was something like 120 miles.

: Now, it it is illegal, then shouldn't you not talk about it here, as
: many of you seem to not want people to discuss linears here.

Why shouldn't people be able to talk about such subjects. We have, at
least for now, freedom to do so in the US. 

: Please, someone tell me what the real deal on this is, I'm
: curious.

I assume that working skip is still illegal. I have not been on the
CB bands in a number of years, so cannot say with any authority. Are
CBers still required to possess (and understand) part 95/97?  of the
FCC regs?

Bill
From: wells@hpfcso.FC.HP.COM (John Wells)
Date: Thu, 15 Oct 1992 18:29:06 GMT
Subject: Re: microphone woes...
Organization: Zanzor of the CLOUDS
Newsgroups: rec.radio.cb

In rec.radio.cb, darrellm@pogo.wv.tek.com (Darrell McGinnis) writes:

> 	The mike on my radio is flakey & I want
> 	to build my own.

> 	I want to use an electret mike (have one)
> 	 & eventually put in a band-pass filter 
> 	 centered around 2-3Khz. 
> 	
> 	Given the current thing is a dynamic mike,
> 	what kind of voltage levels does the radio
> 	expect from the mike ?

Hi,

  I have replaced the dynamic element in several of my radios... both ham and
cb.   The only thing that you will need to do is to be able to supply
a phantom voltage to the mic element while transmitting and to block the 
dc voltage from the input to the audio amp input (usually done by the 
designer anyhow)  There are audio shaping components in the radio already and 
you shouldn't need to mess with it too much... the only thing you might find 
is that there is too much high frequency (treble) and that there may be a bit
of a pop (on the receive end) when the transmitter and mic is "pushed to talk".

  In general, I found the audio voltage level to be simular to the dynamic 
mic and that this mod usually improves the quality of the audio a whole lot
more than even adding a megawatt linear amp!   ;-)  And I don't think this 
really messes with 'type acceptance' since it dosen't tamper with or harm 
the internal workings of the radio.

  As far as schematis are concerned... go to Rat Shack and look at their 3 wire
condenser mic and you will get the idea of how to connect these things.

			Have fun		John in das Fort
Newsgroups: rec.radio.cb
From: wrb@cbnews.cb.att.com (wallace.r.blackburn)
Subject: Re: Continuous Tone Signaling on CB
Organization: AT&T
Distribution: usa
Date: Thu, 8 Oct 1992 12:36:39 GMT
Keywords: CB, CTSS, selective calling, tone actuated squelch, Part 95

>
>A much easier method would be to use a tone burst selective calling system.
>A two-tone system would give you some flexibility and could be easily built.
>All the audio tones would be within the normal voice frequency range.  The
>tones could be inserted at the microphone jack and detected at the speaker.
>No transmitter modifications would be required, hence you could do this work
>yourself.
>
>Commercial systems are readily available.  You can often find advertisements
>in many amateur radio magazines.  You local two-way radio shop may also sell
>aftermarket systems.  At one time Exar Semiconductor had some good application
>notes on tone encoders and decoders.
>
There is an article in June '92 73 Magazine (second time in two days I've
referred someone to that magazine - scary) that shows how to build a
DTMF-based squelch.  Generating the tones would be simple with the
tone-generating chips around today.

Perhaps a tiny microcontroller (the '705K1 or PIC come to mind) coupled
with DTMF generator and decoder chips.  Chips are available that
encode/decode between DTMF and 4 bits.  The correct sequence of tones
simply opens the squelch for 10-15 seconds.  Squelch is a MOSFET that
switches the speaker on/off.


			Wally Blackburn AA8DX
From: edwardl@freddyk.uucp (Edward Langenback)
Newsgroups: rec.radio.cb
Subject: Re: Linear Amps..
Date: 7 Oct 92 12:57:43 GMT
Organization: NightMares R Us

cobra@jab.tucson.az.us (Cobra) writes:

> johnr@mik.uky.edu (John S. Roberts, Jr.) writes:
> > => 75 lines of mindless drivel removed for bandwidth constraints...
> > 
> > Why don't you quit arguing about it al him how to do it.  If you want
> > to talk about policy then start snother thread.
> > 
> > John
> > 
> 
>  
> Seems that Bryan Doyle was *debating* the topic, not arguing 'bout it...
>  

     "debating" is only a polite word for "arguing"
 
  "A difference which makes no difference IS no difference"--Spock


--
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
|                 freddyk!edwardl@engr.uark.edu                 |
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
|                                                               |
|    "He's dead Jim"                                            |
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
From: michaeln@hpcvnb.CV.HP.COM (Mike_Nason)
Date: Sat, 10 Oct 92 19:39:56 PDT
Subject: Re: mobil sideband radio recommendations?
Organization: Hewlett-Packard Co., Corvallis, Oregon
Newsgroups: rec.radio.cb

   Hello, 
     I can only say that I bought a uniden pc-122 ssb radio for a friend of
mine thru that company. The radio was delivered quite promptly and worked 
fine. Other than that I don't know. I'd probably buy another from them.
              Mike Nason KA7HBB.
Newsgroups: rec.radio.cb
Subject: Re: CB tips
From: jonc@status.gen.nz (Jon Clarke)
Date: Sat, 17 Oct 92 10:52:52 GMT
Organization: The Z*NET Global News Gateway. Parnell New Zealand

212ATDX@OwnMachine.fi (DX-pedition) writes:

> There will be 14 AT members on the activation. Please contact US.
>  
> 73 de 56AT485 ( Jari )
>  
> PS. Don't contact me via network I don't have own account.
> 

 Ah well someone tell these chaps that division 41 will be listening

                                                  _
 Jon Clarke                                     o( )       
 jonc@status.gen.nz                            /  /\        GE: J.CLARKE6
 The Z*NET Global News Gateway in Auckland New Zealand      HSBC NZM  EBD