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Author Topic: Basic HF+VHF+UHF station  (Read 4283 times)
KB1EVZ
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« on: September 08, 2005, 01:39:26 PM »

Right now all I have is a 2-meter HT, and, as I'm planning to upgrade to General this month, I'd like to set up some sort of HF station.  I'd also like to have VHF and UHF (at least 2m and 70cm) capability, since my HT only puts out five watts.

My first question is, should I buy a new or used rig?  I don't want to spend a ton of money, but I'd like something relatively modern that works well.  I have an old HF rig at home I borrowed from someone, but it's so old it doesn't even have an digitally-set VFO, just an LED frequency display.  (The VFO itself is all mechanical.)  I don't mind "last year's rig" as long as it works well.

My second question is, should I buy one of the bottom-end HF rigs that doesn't do VHF or UHF and then buy a cheaper mobile rig, or should I spend more and get one rig?  Financially it might actually be cheaper to buy two rigs, but there might be other features of a better HF rig that I would want.

My third question is, what's a good, simple wire HF antenna?  A dipole, obviously.  But I'd like something I can put on my roof (I don't think my parents would like wires running into the backyard), and my house is only 25 feet square.  Even if I run it diagonally, that only gets me down to 20 or 30 meters.  Is there a way to "cheat" the length without running the wires so close to the house that they are dangerously close to people?  If I want to be able to use multiple bands, can I just literally connect several dipoles to the same wire, or do I have to use a switch?  Oh, and is a vertical better than a dipole for a VHF/UHF antenna?

Thanks,

Tom KB1EVZ
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WB2WIK
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« Reply #1 on: September 09, 2005, 10:28:56 AM »

>Basic HF+VHF+UHF station  Reply  
by KB1EVZ on September 8, 2005  Mail this to a friend!  
Right now all I have is a 2-meter HT, and, as I'm planning to upgrade to General this month, I'd like to set up some sort of HF station. I'd also like to have VHF and UHF (at least 2m and 70cm) capability, since my HT only puts out five watts.<

::Congrats in advance on the upgrade.  "HT = 5 watts" isn't the problem with using an HT as a "home station."  The real problem is this: For home station operation on VHF-UHF, unless all you want to do is work a few local repeaters, you need a real antenna.  A real antenna, outside, and elevated enough to have a reasonable horizon, so you can work stuff farther away.  That doesn't take more than five watts, but it does take a real antenna.  Once you connect a real antenna to *most* HTs, they fall apart because their receivers can't handle the wide spectrum of strong signals that start coming down the coax.  Before you know it, you actually don't hear *better* with a good antenna, you hear worse, because the receiver's overloaded.  Conclusion: HTs are for belt clips and portable work, not for home stations.
 
>My first question is, should I buy a new or used rig?<

::That's up to you.  New rig advantages are a manufacturer's warranty, and that you aren't buying somebody else's problems.  Disadvantage is they cost more.

>I don't want to spend a ton of money, but I'd like something relatively modern that works well. I have an old HF rig at home I borrowed from someone, but it's so old it doesn't even have an digitally-set VFO, just an LED frequency display. (The VFO itself is all mechanical.) I don't mind "last year's rig" as long as it works well.<

::There's the conflict.  I read elsewhere you have an FT-707, which is a 24 year-old model that's lacking in many ways.  But I think you wrote it's "borrowed," so this isn't your problem.  The FT-707 isn't "last year's rig," it's a "two decades ago" rig, and everything today is better.

>My second question is, should I buy one of the bottom-end HF rigs that doesn't do VHF or UHF and then buy a cheaper mobile rig, or should I spend more and get one rig? Financially it might actually be cheaper to buy two rigs, but there might be other features of a better HF rig that I would want.<

::The most popular rig ever made is the Icom IC-706MK2(G), and it's popular for good reason.  It wouldn't be my choice for a "home station" transceiver, however a lot of hams do use it that way and most are pretty happy.  It covers 160m through 70cm, all modes, except for the 135cm (222 MHz) band.  It does *not* have a built-in automatic antenna tuner, which most larger "desktop" rigs do.  You'll definitely need some sort of good tuner, either manual or automatic, to go with a rig like this.  I'd recommend a visit to a ham radio dealer if possible to try stuff out and take a few "test drives" of the available gear.

>My third question is, what's a good, simple wire HF antenna? A dipole, obviously. But I'd like something I can put on my roof (I don't think my parents would like wires running into the backyard), and my house is only 25 feet square. Even if I run it diagonally, that only gets me down to 20 or 30 meters. Is there a way to "cheat" the length without running the wires so close to the house that they are dangerously close to people?<

::If you run 100W output power, you can be as close to people as you want with your antenna, as long as nobody can actually touch it.  A perimeter loop antenna 25 square would be 100' long (perimeter) and probably load up okay on 40-10m, maybe even be usable on 6m (with a tuner).  A good HF vertical can be installed on a roof tripod or short roof tower, and models are available that cover lots of bands and can work well if deployed properly.  For VHF-UHF, one "problem" is that if you want to work all modes (mostly, FM and SSB), you cannot do that effectively with any single antenna.  SSB/CW work is *ALL* done using horizontal polarization, and FM/repeater work is *ALL* done using vertical polarization, and the loss when using the wrong antenna polarity is very substantial.  

>If I want to be able to use multiple bands, can I just literally connect several dipoles to the same wire, or do I have to use a switch?<

::With the space limitations you have, you'd probably be better off using a 100' perimeter loop and using it on multiple bands, with an antenna tuner.

>Oh, and is a vertical better than a dipole for a VHF/UHF antenna?<

::Depends on the mode used.  For FM work, you really *NEED* to use a vertical.  For SSB-CW work, you really *NEED* to use a horizontally polarized antenna, and the vast majority use rotary beam antennas, since the whole reason to use SSB or CW on VHF is to work "weak signals" (ones that are way beyond the horizon), and the signals really are weak.  You won't hear many with a dipole, but might hear hundreds with a beam, at exactly the same location.

 
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KB1EVZ
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« Reply #2 on: September 09, 2005, 11:48:49 AM »

> > Right now all I have is a 2-meter HT, and, as I'm
> > planning to upgrade to General this month, I'd like
> > to set up some sort of HF station. I'd also like to
> > have VHF and UHF (at least 2m and 70cm) capability,
> > since my HT only puts out five watts.

> Congrats in advance on the upgrade. "HT = 5 watts"
> isn't the problem with using an HT as a "home
> station." The real problem is this: For home station
> operation on VHF-UHF, unless all you want to do is
> work a few local repeaters, you need a real antenna.
> A real antenna, outside, and elevated enough to have
> a reasonable horizon, so you can work stuff farther
> away. That doesn't take more than five watts, but it
> does take a real antenna. Once you connect a real
> antenna to *most* HTs, they fall apart because their
> receivers can't handle the wide spectrum of strong
> signals that start coming down the coax. Before you
> know it, you actually don't hear *better* with a
> good antenna, you hear worse, because the receiver's
> overloaded. Conclusion: HTs are for belt clips and
> portable work, not for home stations.

Okay.  I'd also like a stronger power level, just in case I want/need to reach farther repeaters.

I'd be happy with some sort of small vertical for VHF and UHF and then the perimeter loop for HF.

> > My first question is, should I buy a new or used
> > rig?

> That's up to you. New rig advantages are a
> manufacturer's warranty, and that you aren't buying
> somebody else's problems. Disadvantage is they cost
> more.

Okay.  I guess it depends on what kind of deals on used gear I can find around Boston (there's always the "junior citizen" discount, where hams see someone under the age of 50 and are willing to give him stuff cheaper to keep the hobby going ;-), how much money I make doing computer work and tutoring this year, and what my parents think.

If I were to buy a relatively recent but used HF rig, can you recommend anything?  I guess I'm looking for something a little better than an IC-718 or TS-840, around an FT-857 or FT-897, but maybe with a "desktop" form factor so I don't have to scroll through pages of "F1", "F2" and "F3" labels to pick a function.

> > I don't want to spend a ton of money, but I'd like
> > something relatively modern that works well. I
> > have an old HF rig at home I borrowed from
> > someone, but it's so old it doesn't even have an
> > digitally-set VFO, just an LED frequency display.
> > (The VFO itself is all mechanical.) I don't mind
> > "last year's rig" as long as it works well.

> There's the conflict. I read elsewhere you have an
> FT-707, which is a 24 year-old model that's lacking
> in many ways. But I think you wrote it's "borrowed,"
> so this isn't your problem. The FT-707 isn't "last
> year's rig," it's a "two decades ago" rig, and
> everything today is better.

Yeah.  I'm trying to think of how to explain this to a non-ham, e.g. a parent.  I didn't use the FT-707 much, mostly because it had only a 10-meter dipole that blew down in the wind a while ago.  Clearly it would be nice to have a newer rig, but it's hard to explain that to someone who doesn't understand the technology. ;-)

> > My second question is, should I buy one of the
> > bottom-end HF rigs that doesn't do VHF or UHF and
> > then buy a cheaper mobile rig, or should I spend
> > more and get one rig? Financially it might
> > actually be cheaper to buy two rigs, but there
> > might be other features of a better HF rig that I
> > would want.

> The most popular rig ever made is the Icom
> IC-706MKIIG, and it's popular for good reason. It
> wouldn't be my choice for a "home station"
> transceiver, however a lot of hams do use it that
> way and most are pretty happy. It covers 160m
> through 70cm, all modes, except for the 135cm (222
> MHz) band. It does *not* have a built-in automatic
> antenna tuner, which most larger "desktop" rigs do.
> You'll definitely need some sort of good tuner,
> either manual or automatic, to go with a rig like
> this. I'd recommend a visit to a ham radio dealer if
> possible to try stuff out and take a few "test
> drives" of the available gear.

Oh, believe me, I would love an IC-706MKIIG.  I used one at a field day once; it's an awesome rig.  I'm also looking at the FT-847D or FT-897D from Yaesu.  The 847 is about the same size as the IC-706MKIIG; the 897 is a little bigger, maybe one and a half times as tall.

> > My third question is, what's a good, simple wire
> > HF antenna? A dipole, obviously. But I'd like
> > something I can put on my roof (I don't think my
> > parents would like wires running into the
> > backyard), and my house is only 25 feet square.
> > Even if I run it diagonally, that only gets me
> > down to 20 or 30 meters. Is there a way to "cheat"
> > the length without running the wires so close to
> > the house that they are dangerously close to
> > people?

> If you run 100W output power, you can be as close to
> people as you want with your antenna, as long as
> nobody can actually touch it. A perimeter loop
> antenna 25 square would be 100' long (perimeter) and
> probably load up okay on 40-10m, maybe even be
> usable on 6m (with a tuner). A good HF vertical can
> be installed on a roof tripod or short roof tower,
> and models are available that cover lots of bands
> and can work well if deployed properly. For VHF-UHF,
> one "problem" is that if you want to work all modes
> (mostly, FM and SSB), you cannot do that effectively
> with any single antenna. SSB/CW work is *ALL* done
> using horizontal polarization, and FM/repeater work
> is *ALL* done using vertical polarization, and the
> loss when using the wrong antenna polarity is very
> substantial.

The output power limit before you need to do an evaluation is 225W on most HF bands, right?  (I should know, it's on the exam, I think it's 225.)

> > If I want to be able to use multiple bands, can I
> > just literally connect several dipoles to the same
> > wire, or do I have to use a switch?

> With the space limitations you have, you'd probably
> be better off using a 100' perimeter loop and using
> it on multiple bands, with an antenna tuner.

Okay.  How complicated and/or annoying is a manual tuner, or should I just get an automatic one?  If there is one that integrates with a rig (FC-30 for FT-847, IIRC), is it a good thing to get that one, or are they not as good as independent ones?  Can you recommend a good one of either type (manual or automatic)?

> > Oh, and is a vertical better than a dipole for a
> > VHF/UHF antenna?

> Depends on the mode used. For FM work, you really
> *NEED* to use a vertical. For SSB-CW work, you
> really *NEED* to use a horizontally polarized
> antenna, and the vast majority use rotary beam
> antennas, since the whole reason to use SSB or CW on
> VHF is to work "weak signals" (ones that are way
> beyond the horizon), and the signals really are
> weak. You won't hear many with a dipole, but might
> hear hundreds with a beam, at exactly the same
> location.

I'm probably not planning to do 2-meter SSB-CW work (yet), mostly because I'm upgrading to General precisely to get privileges on lower bands.  What's a good vertical then?

I would rather build an antenna in most cases than buy one, especially if it's relatively simple, just because something that costs $100-$200 can be built for probably $30-$50 in parts.

Oh, might it be a good idea to have separate HF and VHF/UHF rigs so I can monitor packet clusters, or is Telnet good enough for that?

Just for reference, what's a reasonable price for a basic HF station to aim for?  (Or is that impossible to quote because it depends on new/used rig and commercial/homebrew antenna, etc...?)  I'm just looking for a ballpark figure to know what is reasonable to buy.

Thanks for your help!
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WB2WIK
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« Reply #3 on: September 09, 2005, 01:58:06 PM »

A good manual tuner costs about as much as a decent 100W auto-tuner, so I'd go for the automatic tuner if possible.  Here's a good one that works with *any* rig, of any manufacture:

http://www.ldgelectronics.com/at-100pro.html

There are others, from LDG as well as SGC, MFJ, Icom and Yaesu.  I think the LDG's a "best buy," but that's just my opinion.

You can homebrew a 2m/70cm vertical antenna, but I honestly believe this is usually not a great investment of resources (time + money).  It's really difficult to build a *strong* antenna that will survive outdoor climates in Boston (wind, ice, snow) and do so any more cheaply than simply buying one that will definitely do the job.  The ubiquitous "j-pole," for example, can be assembled for probably $20 in materials, and then you have a so-so antenna that's not a great performer and may not withstand the first good winter storm if mounted on your roof.  Most j-poles are made of copper tubing to keep them simple, and copper's weight-to-strength ratio is horrible.  It's heavy, and not terribly strong.  Aluminum's much better, but problematic because it cannot be effectively soldered using conventional materials and as such requires a lot more drilling, screwing, clamping and other stuff.

Comet, Diamond, Hustler, Cushcraft and others make perfectly good 2m/70cm vertical omnidirectional antennas that mount easily to conventional antenna masts and will withstand 70 mph winds, even when ice-coated.  They cost in the $100-$150 range and are a worthwhile investment.  I know, having lived there, Boston's a windy place.

Regarding "power," on VHF-UHF FM, you don't need much if you have a good antenna.  100W into a crappy antenna doesn't work anywhere near as well as 5W into a good one.  I routinely work FM-simplex (not repeaters) on 2m FM (like 146.52), working mobiles out to about 75 miles, running exactly 5W from my home -- to a good antenna up sixty feet.  I could run a kilowatt and not make those contacts if I used a ground plane at 20 feet.  I mostly wouldn't make them, because I wouldn't be able to hear them.  The antenna's the important part of the station.

An IC-718 is a "best buy" rated rig.  Simple, easy to set up and use, works.  It lacks some features, but has most of the one's you'd need to simply get on the air and make contacts -- if used with a good antenna tuner (it doesn't have one built-in, but then neither does the IC-706MK2G or the FT-857, or the FT-840 or any of the rigs in this size/price class).

As for a "budget," let's see: If you buy all new stuff...

IC-718 is about $600.
LDG smart auto tuner is about $220.
Good external balun for that, if you want to use twin lead or ladder line for the loop, $30.
Good VHF-UHF omni vertical is about $150.
Coax, allow probably $75.
Antenna hardware (misc), $30.
Materials to build loop (wire, insulators, etc), $25.
Ladder line for loop, $20.
Power supply for station including IC-718, if you don't already have a suitable one, $140.
Total = $1290.

This might be a recommendable approach for a newcomer, if you have the budget.

Frankly, if it were me (and I'm not a newcomer), if I had $1290 to spend, I'd spend about $1000 of it on antennas, and find a junky old used rig someplace to use them with.  That would be a better investment for me, because I don't mind old gear and greatly prefer good antennas!  But that approach isn't for everyone.

73!

Steve WB2WIK/6


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KB1EVZ
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« Reply #4 on: September 09, 2005, 04:31:39 PM »

$1290 looks like a bit more than I wanted to spend, although I may not need everything you listed.

A few more questions:

1. If I make a 100+ foot random wire antenna, can I feed it with coax or ladder line?  Are there reasons to do it one way or the other?
2. If I make a random wire antenna, how do I feed it?  Do I ground the shield of the feedline and then attach the core to the wire?
3. If I have a manual antenna tuner from the FT-707, is it a) usable and b) worth using?
4. What should I look for in an antenna tuner?
5. Is it worth buying a separate SWR meter that has more than the 0.2 SWR resolution of the meter on the tuner.
6. If I do that, can I buy a cheaper tuner without a meter and use the real meter?
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WB2WIK
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« Reply #5 on: September 10, 2005, 03:26:04 PM »

 
>RE: Basic HF+VHF+UHF station  Reply  
by KB1EVZ on September 9, 2005  Mail this to a friend!  
$1290 looks like a bit more than I wanted to spend, although I may not need everything you listed.

A few more questions:

1. If I make a 100+ foot random wire antenna, can I feed it with coax or ladder line? Are there reasons to do it one way or the other?<

::A "random wire" is usually end-fed, in which case you certainly would *not* want to use coax to feed it, and even ladder line isn't necessary.  The most effective feed system is to bring the "rig" end of the wire right to the tuner, directly, without any transmission line.  In this case, the tuner must be well grounded (RF ground), which means it needs to be close to earth to be effective.
 
>2. If I make a random wire antenna, how do I feed it? Do I ground the shield of the feedline and then attach the core to the wire?<

::No, see above.
 
>3. If I have a manual antenna tuner from the FT-707, is it a) usable and b) worth using?<

::Of course it would be worth using.  There's nothing wrong with manual tuners except they take time and skill to adjust.  Before automatic tuners became available for amateur use, which was only maybe 15 years ago or so, everybody used manual tuners.
 
>4. What should I look for in an antenna tuner?<

::The bigger, the better!  That is to say, a "1 kilowatt" (or higher) rated power tuner does a better job of matching antennas, even if you only run 5 Watts.  This is because its internal components are larger and will have less loss -- a factor that's even more important when you run lower power.
 
>5. Is it worth buying a separate SWR meter that has more than the 0.2 SWR resolution of the meter on the tuner.<

::No.  Absolute accuracy or great resolution in an SWR meter is not important at all.  Tuning for a "dip," or the lowest SWR possible, is the only important thing, and as long as you can find a "dip," it doesn't matter if the meter reads 1.0, 1.2 or 1.4.  Who cares?  Minimum is minimum.
 
>6. If I do that, can I buy a cheaper tuner without a meter and use the real meter?<

::You could, but a meter in a tuner *is* a "real meter."  There's no difference in the circuitry between an "internal" (inside the tuner) meter and an "external" (separate component) SWR bridge/meter, except for its physical location.  The circuits remain the same, as do the accuracy.  

-WB2WIK/6
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KB1EVZ
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« Reply #6 on: September 10, 2005, 07:59:06 PM »

Well, $1290 is too much.  Right now, I have the following (it doesn't include everything):

Power Supply: Astron SS-30 (switch mode 25 amp cts./30 amp peak power supply): $129.95
Transceiver: Yaesu FT-857D: $689.95
Antenna Tuner: LDG Electronics AT-100 Pro: $209.95
Balun: RBA-4:1: $30.95
Total: $1060.80

It's still a bit high for my liking, though, but I'm a) a student and b) cheap, so...

I'm hoping I can find one or more of those used for cheaper.  The radio I will only buy used if it's relatively lightly used (I don't want something that sustained heavy use for a long time, just something someone doesn't want.) but the power supply and antenna tuner just have to work.

As for antenna hardware, what's a good brand of cable and miscellaneous hardware?

Oh, and if I split the random wire in half and turn it into a dipole, does it need to be longer than the random wire would have been?  A dipole is a half wavelength; what does a random wire need to be to work well?
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KB1EVZ
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« Reply #7 on: September 10, 2005, 08:00:49 PM »

Oh, by "have" I meant "have in mind as what I wanna buy", not "have already purchased". ;-)

I'm drooling over the tons of PSK31 signals I'm getting on 40m with my 10m dipole hooked up without a tuner and lying half crumpled-up on the bed... having a General Class license is gonna ROCK!

73's de KB1EVZ
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WB2WIK
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« Reply #8 on: September 11, 2005, 08:38:32 AM »

You can make a dipole any length you want.  The definition is an antenna made from two equal length wires, and that's about it.  Frankly, the wires don't have to be equal length, either, although making them equal length helps achieve a "balance."

A dipole is resonant where it is electrically 1/2-wavelength long, or any integer of 1/2-wavelength long (e.g., 1WL, 1.5WL, 2WL, 2.5WL, 3WL, etc).  However, just because it's resonant doesn't mean it's useful.  A dipole feedpoint resistance goes through a "useful" range at .5WL, 1.5WL, 2.5WL, 3.5WL, etc. -- all *odd* multiples of 1/2 wavelength.  On the even multiples, it's resonant, but has a very high feedpoint resistance that makes it very difficult to match, even using a good tuner -- and you *definitely* cannot feed such an antenna with coaxial cable.

A "random" length dipole should simply be made as long as possible and fed with open-wire or ladder line, to a balanced tuner.  That's it.  No use making calculations, because "the longest possible" is the best, and your property will dictate what that is.

If it's easier to achieve one high support point and two lower end points, and this allows space for "more wire" (longer dipole), then that's often a good alternative: An inverted vee.

If you buy a used rig and want to be sure of its condition, buy it locally from somebody you can meet in person, and check the rig out on all bands and all features before buying it.  Can't do that over the internet.  Another option: Buy a used rig from a major dealer, who offers a warranty on used gear.  AES does this.

Good luck!

WB2WIK/6

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KB1EVZ
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« Reply #9 on: September 11, 2005, 12:18:49 PM »

Is a balanced tuner significantly different from a regular (coax-connected) tuner followed by a balun?
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WB2WIK
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« Reply #10 on: September 11, 2005, 01:37:48 PM »

Actually, it is significantly different.  But a single-ended or unbalanced tuner (intended for coaxial input/output) followed by a good 4:1 current balun isn't a bad substitute.  

Most all the commercially built manually tuned unbalanced tuners on the market have a built-in wideband balun (inside the tuner case), providing binding post type balanced line connections.  Most of the automatic tuners don't, so if you choose an auto tuner that does not provide balanced line connections, you'd need an outboard balun.  

WB2WIK/6
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KB1EVZ
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« Reply #11 on: September 12, 2005, 06:10:44 PM »

Wheeeeeeeee, say hello to KB1EVZ/AG!
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K7VO
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« Reply #12 on: September 18, 2005, 04:06:33 PM »

Congratulations on the upgrade!

73,
Caity
K7VO
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