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As an experiment, I'm starting this post. If you have questions about amateur radio just ask. If you have an answer to a question, post it!
 
Setting up a mobile station

Alright, you passed your tech exam, got your callsign, now what? You look in the magazines and catalogs and are confused by all the choices in radios and antennas. VHF, UHF, Dual band, dB, dBi, dBd, all the features, what do or don't I need?

First we'll start with the transciever. Resist the temptation to buy an HT (Handie-Talkie) right off the bat. While they're great for short distances on foot or for a nearby repeater, they lack the power to get a signal out when you're out in the field.
If cost is a consideration, consider a simple 2M FM mobile. Two meters is where you'll find a majority of repeater and simplex traffic. Most 2M radios will put out a respectable 50 watts or higher, which is more than enough to hit any repeater you can clearly hear. The prices are generally between $150 and $200. Used radios can be significantly cheaper, but let the buyer beware.
Dual band radios cover the 2 meter and 70 CM (also called 440) bands. They range in price from $250 to $800 depending on the features included. One feature that comes in handy is dual receive, where you can listen to both bands at the same time. This comes in handy when you are on a SKYWARN net on 2M, and a group of chasers in your area are on 440 simplex. Cross band repeat can also come in handy. If you get out of your vehicle to photograph or video, you can use the mobile to retransmit the low power signal from an HT, thereby freeing you from being right around the vehicle.
I wouldn't reccomend tri-banders, quad-banders, or all band dc to daylight rigs unless you are interested in doing more with ham radio besides storm chasing.
Mount the rig solidly in your vehicle to avoid it becoming a projectile in an accident. Consider getting an external speaker, you'll be much happier with the audio quality. Mount this solidly as well. Run the power leads through the firewall and directly to the vehicle's battery. Terminate the wire ends with ring terminals that fit your battery terminals, and the power leads.

Next we have antennas. Antenna advertisments can be the most confusing and downright misleading aspects of equipment shopping. Obviously, get an antenna to suit the radio you have (monoband, dualband, ETC...). You'll soon be asking what length and gain are all about. Gain is how much effective radiated power an antenna puts out when compared to another antenna, and is expressed in decibels (dB). A good rule of thumb to remember is that doubling your power is a gain of roughly 3dB.
Antenna companies will use gain figures to mislead you into thinking their antenna is better than a compareable one by playing with the gain figure. They will express gain in dBi, which means the antenna is being compared to an isotropic radiator, which is an imaginary point in free space that radiates in a perfect sphere. In reality, no antenna works like that. A more realistic reference is dBd, which compares the antenna to a halfwave dipole or a quater wave vertical. Subtract 2.15dB from dBi to get a realistic figure.
A commercially made 20 inch dual band antenna advertises 2.15dB on 2M, and 3.4 dB on 440. Adjusting the figure to dBd gives you 0dB on 2M, and 1.25dB on 440. There is no gain on a 20 inch antenna on 2M, because 18 inches is a quater wave at that frequency. As a half wave on 440, you will not even see a 50% increase in Effective Radiated Power (ERP).
By now you should be asking how does an antenna boost my power? Well, it doesn't. What a gain antenna really does is focus the signal towards the horizon so that the radiation field would look more like a disc than a fat donut. So your 50W radio is still putting out 50W, but it is all shooting towards the horizon instead of up to the sky and down to the ground. More of your signal goes where you need it.
Get the longest antenna you can comfortably put on your vehicle. Keep in mind tree limbs, drive-thrus, and garages. The longer the antenna, the higher gain you will get out of it.

Now that you have your antenna, how to mount it? When at all possible, drill a hole in the vehicle roof and use a through hole hard mount. That can be a horriffic thought to those owning newer nice vehicles. Using a mag mount does much more damage by scratching the paint, and rust sets in (I know this from firsthand experience). Mag mounts couple weakly electrially with the metal it's mounted on, and you will not see the full gain the antenna is capable of. A good ground plane is needed to get the most out of an antenna, and many will not function without a ground plane. The door, bumper or trunk mounts will work decently, but they are a compromise. You will not see the full potential in gain, and the antenna will become directional, that is, more powerful in the direction the most metal is. If you can't bear the thought of drilling a hole in your vehicle, use one of these.

Next is something most people don't give much thought to, coax. Don't use a longer run than you really need, but use at least six feet. Find a way to get the coax outside without pinching it in a door or window. Pinched coax will have an impedance of more than 50 ohms, and will throw the VSWR off. Try to use an existing through hole for the vehicles wiring harness, or running through the molding and headboard if using a thru-roof mount.

Use an SWR meter marked for use with VHF/UHF and check SWR in an open area at least fifty feet away from any buildings, telephone poles, wires, lightpoles, ETC... Check SWR at the bottom, center, and top of the band, and see where the lowest point is. If the lowest SWR is too low in frequency, adjust the antenna so it is shorter. Conversely, if the lowest SWR is too high in frequency, make the antenna longer. Adjustment is usaully done with an allen key from the bottom of the whip. All that is needed is a change of 1/8 inch to change SWR significantly. If the SWR is off the scale no matter what you do, check the coax, connections, and antenna ground. Check this before cutting the antenna shorter.

Get out and enjoy your new setup, hit some local repeaters and get some signal reports. If something's wrong, most hams will offer advice on remedying the situation. More often though, you'll get compliments on the job you did!
 
Pat- are there any HAM antenna books or other sources that have plans for building a homemade mobile WiFi antenna ? Could you use an old mag mount 2M antenna cut down to the Wifi frequecy/ wavelength whatever that is ? TNX

Jon Miller
WTØRNA
 
Pat- are there any HAM antenna books or other sources that have plans for building a homemade mobile WiFi antenna ? Could you use an old mag mount 2M antenna cut down to the Wifi frequecy/ wavelength whatever that is ? TNX

Jon,
It is possible, but can be difficult. . Cutting a whip to get a quater wave at 2.4GHz would leave you with a whip barely 1.2 inches long. That doesn't give enough capture area to get a solid copy on a signal, and at 2.4 GHz, losses through the feedline, trees in full leaf, and even rain will attenuate your signal enough to eradicate it. For microwave frequencies, high gain antennas are a must. The easiest design I have found would be an omnidirectional colinear vertical (the same design as the high gain verticals for 2M and 440, but scaled down). I found a fairly easy to construct one at http://wireless.gumph.org

Construction will require sharp eyes, a steady hand, and some soldering experience. The parts you will be working with, and areas to solder (and not to solder) will be small.[/url]
 
-.-. --.-

How did you ever get above 20wpm using CW? I am struggling at 10 or less. There are many different opinions on the methodology, I was curious how you did it.

73,
KE5BAU
 
How did you ever get above 20wpm using CW? I am struggling at 10 or less. There are many different opinions on the methodology, I was curious how you did it.
Patrick, KE5BAU,
I started my CW journey with two programs, G4FON's Koch Method (freeware) and Numorse (shareware, but well worth the price).

First I learned the characters. After that I would cut and paste articles and stories I wanted to read to Numorse. The program will play back the text in CW at whatever speed you set it to. When I could almost copy all of it perfectly, I'd bump up the speed 1-2 WPM. Within six months, I went from 7-10 WPM to 20+WPM!

Koch Method starts you with only 2 characters at 20 WPM. When you know those two, it will bump it up one. You tell it to add characters, it won't do it automatically and overwhelm you. once you know all characters, including numbers punctuation and prosigns, you can set it to send random common words.

If you're still using pen and paper to copy, put them away! Get used to listening, and forming the words in your mind. This cuts out a step in the thought process. The sounds go directly into your mind as letters instead of translating on paper first. As you listen to CW, begin sounding the word in your mind syllable by syllable instead of spelling it letter by letter. This will make it feel more natural, and the words will begin to flow smoothly.

Most importantly, don't burn yourself out. Practice 10-15 minutes at a time, then take at least a half hour break. This will keep your mind fresh. If you begin to get fustrated or tired, take a break and come back refreshed. You'll find what you were stuck on coming smoothly.

Try as many different methods as you can, and find out what works best for you. I used to drive a truck for a living, and would use my laptop to play CW as I drove, kind of like "books on tape". Long hours on the road gave me plenty of practice time.
 
I recently received my call sign and I have a dual band mobile rig. Now I need to purchase a dual band mobile antenna. I read in previous post about a glass through antenna which sounds interesting. My SUV is new, and still under warranty, so I am not too interested in a hard mount at this time. I had not thought about what damage a mag mount could do, thanks for that info. I do like the idea of being able to quickly move my mobile set up from one vehicle to another as I own two, and I may possibly take the set up on a my next out of state vacation. Let me know what you would suggest in my case and also, some suggestions on a good place or places to purchase an antenna and other ham equipment too.

Rodger
KI4HJF
 
I read in previous post about a glass through antenna which sounds interesting. My SUV is new, and still under warranty, so I am not too interested in a hard mount at this time.

Rodger, KI4HJF,
First of all, congratulations!

I have a glass mount dual band on my pickup as a back up. They work well enough, but they can't handle much power. They got very hot at 50W, which is the limit of what they can handle. They also transmit poorly due to lack of a ground plane. These antennas definately suffer when you are far from a repeater.

Diamond, Comet and MFJ make mounts which should suit your needs. If you have a luggage rack on the roof, that type would be the best. They clamp right on to the luggage rack, and can be removed in minutes. You would be able to place the antenna closer to the center of the roof to take advantage of the ground plane. If you don't have a luggage rack, there are mounts that will attatch to the top of a door or hatchback. They tighten with allen screws, and have a rubberized back that won't scratch the paint. They are also easy to move to another vehicle.

Along with these mounts, they make coax assemblies that have a short length of very thin coax that won't pinch in the door or damage weatherstripping. Mobile applications use coax runs short enough where loss through the cable isn't a factor to worry about.

Suppliers on the net abound. These are a few off the top of my head that have a wide selection.
www.aesham.com
www.gigaparts.com
www.hamradio.com

Again, welcome to the world of ham radio!
 
Congratulations Rodger! Welcome to the hobby!

This is great Pat, great answers, and great questions from everyone.

...Now, how do I hook up the Christmas lights on the outside of the house to my paddles so I can send CW blinking to the neighbors, hmmmm... :lol:

By the way, for those interested in a bit of history, I am reading a book titled Signor Marconi's Magic Box. It is written by Gavin Weightman. The book is about Marconi's invention of the first wireless transmitter. It's a great book for amateurs, or anyone else interested in radio for that matter.

73 de Tim
 
...Now, how do I hook up the Christmas lights on the outside of the house to my paddles so I can send CW blinking to the neighbors, hmmmm...

Tim,
You could wire a straight key right into the power cord, and make sure the knob is insulated.... :shock:
To use a paddle, wire 2 relays in parallel into one side of the power cord, run the control leads off the relays to a 1/4" stereo jack, and plug a keyer in. Your neighbors will look quizzically at your house for sure! :D
 
David,

From what I can tell in browsing the manual for the IC2720 online, it does not have the cross-band function on it.

EDIT: After looking at the product listing on Ham Radio Outlet, I think I see where the confusion comes from.

"V/V, U/U, V/U, U/V (Work dual or cross band)"

Their cross band reference is to the ability to use one channel on UHF while using the other channel on VHF. This is not Cross-band Repeater, but the ability to use the two separately. That is, unless I am missing something all together.

Tim
 
That's exactly what that means.

My Yaesu FT7100M mentions that V/U, U/U junk, and is referencing receive, not repeat.

That's one function I wish I had on my rig, though aside from that it's a good mobile.

mp K5TVT
 
Morgan,

Did you have problems with the 7100M? I got one three years ago, and it had serious transmit audio problems. Six months and three times in the Yaesu tech center and it was finally fixed. It also has a very wide RX, lots of intermod on the sub band.
 
Thanks for the info, I could never find anything that would help me figure it out, but it makes sence, v/v, v/u so on, and so on.
:roll:
 
Pat, I read in one of the first posts that you made about an HT radio. I have had my call sign for around a month now, but still have no radio or anything. Money is a major issue it you get what I am saying, so what are the main problems with a HT radio?? I know they will not get you much power, but it is one of the only things I can afford. Just wondering your thoughts on this... Thanks
 
Originally posted by Jayson Prentice
Pat, I read in one of the first posts that you made about an HT radio. I have had my call sign for around a month now, but still have no radio or anything. Money is a major issue it you get what I am saying, so what are the main problems with a HT radio?? I know they will not get you much power, but it is one of the only things I can afford. Just wondering your thoughts on this... Thanks


Jason, congrats on your ham ticket! HT's are OK to start with. I think what Pat is trying to get accross is, at best, an HT is going to put out roughly 5 watts, if that much (depending on the model). This is OK if you are in town and close to a repeater. On a mobile 2M radio, you can pump it up to around 50 watts if needed.

In reality, you should probably be able to pick up a used 2M radio in the $100 range. I bought an icom 229 as a backup for 100 bucks not too long ago, and it works great. Check with a local Ham club as they usually have sidewalk sales once a month. If your funds are limited like you say, this would probably be your best bet.

A pic of the ic-229

[Broken External Image]:http://www.mods.dk/pic/icom/ic-229.jpg

A single band 2 meter is fine. Dual Band (2m and 70cm-440) is nice, but depending on the area you live in, there probably isn't too much happening on 70cm - 440. I think you would be fine with a single band 2 meter mobile. If your lucky, the person selling the radio might also have an antenna they will throw in. Alot of hams are nice this way, and like to help out beginners.

Check out www.arrl.org and follow the "clubs" link to find a local ham club in your area.

Good luck!
 
Jayson,

For the price of a lower end HT, you can get a lower end 2M mobile like the Icom 2100H, Kenwood TM-271A, or Yaesu FT-2800M. All are priced in the $150-$200 range.

HT's are great if you backpack a lot, or live in a metropolitan area with lots of repeaters nearby. But when on the backroads, 5W won't get you very far (10 miles at best). This problem is made even worse if you use the rubber dickie antenna inside the vehicle. They also get quite hot after a moderate length QSO. The other issue with HT's is the audio quality, both on transmit and recieve. The small speaker inside an HT delivers substandard performance. The standard condenser mic isn't quite so bad, but I prefer a speaker mic so my head isn't right next to the HT when transmitting.

Setting up an HT to work well and comfortably can cost more than buying a mobile. A speaker mic adds about $30, and buying a 18" 1/4 wave/ dual band antenna adds another $30. Believe me, you will want to replace the cheap helically wound rubber duckie the HT comes with! Add another $30-$50 for the 12V power cord if you don't want your batteries to die after an hour.

A mobile comes with a decent mic, power cord, and a speaker somewhat better than the one in an HT. The only extra expense is an antenna and mount. I bought a simple 5/8 wave 2M antenna with 3/8x24 thread for $25. A cheap CB bumper mount and length of coax can be had for less than $20 at Radio Shack (you got questions, they got blank stares :D )

Try looking around at a hamfest for a used mobile. You could find one on E-bay, but I've always been wary of used equipment and e-bay in general. Most of the catalog and internet merchants offer used/demo radios with a limited warranty, but you'll only save $20 or so.

If you're saving up cash for a rig, wait a few extra pay periods and get something you'll feel happy with, instead of settling for less of a rig.

Hope this helps. Feel free to ask about anything else, and WELCOME TO THE HOBBY!
 
:lol: I figure if I'm going to get advice, I might as well get it here. Sorry if I'm being a pain.
I've narrowed it down to either a Kenwood TM-271A, Icom IC-2100H, or an Yaesu FT-2800. Does anybody have experience with these and had any problems, or any type of comment on these? I've looked at a couple different sites for prices, but wondering what is the best site that you know of for buying radios?? I know I have found a lot of off sites, such as the austin amatuer radio store, or other stores such as that. Should I just go with the lowest price that i can find anywhere, or is there an outlet store that should be cheap and have good support.
Thanks
 
Hey if your still looking for an HT I have a Icom IC-V8 5.5 watts 2m and works great. i got mine for 124$ so just search around compare prices.
 
The way it looks, is that I am going to go with a mobile.. I have found a couple different ones from 175 to 225... I'm better off going with the power and the mobile accessories than with a HT.
 
I'm not a very big fan of Icom radios, so I can't recommend any of those. The other two are a pretty close match. The biggest difference I see is that the Kenwood only has 100 memory channels when alphanumerics are used for channel names. According to what I read the Yaesu keeps its 221 channels no matter what naming. They both have a wx alert, which I wish I had.

Take a look at the E-Ham reviews and see what you think. Both radios have a lot of reviews.

Yaesu FT-2800M: http://www.eham.net/reviews/detail/3077

Kenwood TM-271A: http://www.eham.net/reviews/detail/3684
 
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