Time to talk about antennas and feed lines

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Linnea
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Time to talk about antennas and feed lines

Post by Linnea » 06-16-2003 11:42 PM

We could use an antenna thread here. {{share info, experiences, etc }} Hitchhiker shared info about his antenna. Maybe he could repost the particulars again here. Juno - are you getting an antenna set up? John? How's the stealth model coming along?

So far, I have a good 2 meter vertical, and an 80/75 meter dipole that needs some work. Could use some advice on that. I am able to pull in a clear signal on 3840, but the stations further away are much fainter. Should I change the orientation of the wires? How should I configure the antenna for better gain? Would getting an antenna tuner help bring in the more distant stations?

I think I have too much loss along the feed line. I am using two 50' lengths of R58 coax - with a connector, running from the balun center feed. I have some regular ladder line, and had a suggestion to run the ladder line out from the center feed - and attach the coax at the end - to run into the shack. I've heard that R8 coax is better for lengths over 50 feet...

Any ideas?

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Post by Gwen » 06-17-2003 08:38 AM

Linnea, have you checked out this site: http://www.cebik.com/radio.html There is mucho info about antennas here. I don't have a base unit yet, so am not into that yet. When I do, I think I will get the Antenna Book...I need to see things on paper, not just on a monitor.

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Post by Linnea » 06-22-2003 03:53 PM

Cebik is fantastic! Yes, I have visited his website. Maybe should do some more reading there.

I think I have figured out that I have a problem with line loss. With a frequency, you are either tuned to it or not - I think. So the problem with fainter signals may have to do with line loss. There is more equipment I am going to need. A SWR meter for sure. There is one on the ICOM, but I do not have an antenna switch, dummy antenna - or a transmatch, etc.

There are things that one must do to get the best possible signal in and out - and safety considerations also. An RF meter in the shack would be a good idea - if you are going into transmission and not just SWL.

When I joined ARRL I got a complimentary copy of the book: On the Air with Ham Radio, by Steve Ford WB8IMY. It is a good guide to radio communications set up, and the different equiment you need for many different projects. I guess we will all need some extra bucks to get this stuff! :D I want to get a paddle code keyer too, and see if I can get some code practice in with some patient hams out there.

Thanks for the response, Gwen. Don't know why some of our other hams don't check in here to help us newbies out a little more. Heh :rolleyes:

Well, we live in stressful times, and I suppose everyone has a lot of issues to deal with. I know I do.

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Lastmartian
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Antennae

Post by Lastmartian » 06-23-2003 12:27 PM

Hi Gwen and Linnea,
I'm a newbie ham myself but I hope I can help with some things. Generally when you ask a ham about antennas you get a whole lecture.
When I lived in Port Townsend the house was surrounded by red cedars and they make great antenna trees. I had a multi-band dipole and it worked great with a tuner. Out here in Sequim there are no antenna trees so I put a vertical on the roof. Rg-58 is very lossy in runs over 50 ft. RG-8 is better and there are even better coaxial types if you want to spend more. But 450 ohm ladder line has very low loss characteristics. The drawback is that it can't be too close to anything metal. You also need a balun, which is a feed line transformer to bring the impedance down to about 50 ohms which is what solid state rigs prefer. Many tuners have a balun built in. A tuner is almost a necessity for transmitting, and it's usefull even for just recieving. MFJ makes some affordable ones and they're ok. I see them on Ebay all the time. Dipoles work best when you can get them as high off the ground as you can: at least half the wavelength of the lowest frequency is what I understand. But this isn't always possible. Dipoles have the most gain when they are perpendicular to the desired signal. So to recieve Mr. Bell from Washington the antenna should be located with the wires running roughly from east to west.
If you are learning code it's best to stick with the straight key before you move up to a paddle or a 'bug'. One of the best things I used to learn code was a morse code tutor sold by MFJ. It generates code characters in a variety of ways and the word and character speeds are adjustable. It generates random character groups, whole words, and also practice QSO's as well as other things. It's better than the tapes because you can memorize the tapes after awhile and you don't learn anything. The tutor is the size of a pager and has a speaker as well as a headphone jack. They cost about eighty dollars but I think they're worth it if you want to learn code beyond just passing the 5 wpm test.
I hope some of this helps, and you can certainly ask me more questions.

Ken W
Last edited by Lastmartian on 06-23-2003 12:34 PM, edited 1 time in total.

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Post by Hitchhiker » 06-23-2003 02:11 PM

Antennas are a subject for endless discussion; I know guys who just about devote their lives to building different kinds of antennas. Eventually, you'll ruin at least one antenna by cutting it too short trying to set the SWRs.
Proper tuning can make a world of difference. The last time I tuned my 10-meter antenna, a half-inch clipped off the end made the difference between hearing nothing and hearing stations 3000 miles away. An antenna tuner will definitely help. Line loss shouldn't be that big of a problem unless you've got a run of more than 50 feet, in which case you'd want to use RG-8.

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Post by mudwoman » 06-23-2003 07:36 PM

Lastmartian I just read your post and hung on every word. I live 9mi. S of Port Townsend in Chimacum.

If you would like to post or email me more about your dipole set up I would love to hear more. I sure have the trees, even have them picked out.

I would like to hear about your rig and tuner also. I bought a RS HTX-100 on eBay for $25. It was in the box and in great shape but w/o the manual which RS no longer carries. I found on (where else) eBay though.

I am also looking at the MFJ Versa Tuner 949 D or E on eBay.

Being a tech only what do you think? ALL info loved and respected. I am so tired of books and websites where I hear (as you pointed out) something different from every HAM.

Thanks a bunch :D

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Antennae

Post by Lastmartian » 06-23-2003 08:06 PM

Hi Mudwoman,
I live in Sequim now but I first set up my station while I lived at my mother's place in Kala Point. The dipole was made by Van Gorden antennas. It's called the "shorty multi-bander". It's a 70 foot dipole with loading coils that make it 135 ft. electrically. It has to be used with a tuner but it tuned up in all bands, although it was a little difficult to tune at 40 meters. It was fed with 450 ohm ladder line because of the varying impedance when it's tuned to different bands. Coax likes 50 ohms impedance and if the impedance is high coax can radiate rf energy. I got it up in the trees with a sling-shot combined with a fishing reel. I made it myself but you can by these things on Ebay. I lost a lot of fishing weights and line but I finally got it up there. In fact it's still there. The nasty winds we get here didn't bring it down.

My present set up is an old but trusty Icom IC-740. The antenna is a Diamond six band vertical my landlord let me install on the roof. The tuner is an old Drake tuner but I think I'll get my MFJ roller inductor tuner and try that here. MFJ tuners tend to be a little chintzy in my opinion but they're affordable. If you buy on on Ebay make sure you know the price of a new one. I've seen people bid near the new price for a used tuner.

I have an HTX-100 in my truck. It's a great 10 meter rig. I have the original manual too. I can scan it and send it to you. Let me know your e-mail if you want the manual.

73 de KD7IZU or just Ken

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Post by mudwoman » 06-23-2003 09:33 PM

KD7IZU (or just Ken):D

Thanks so much. Will check out the Van Gorden.

I went to the RS web site. They no longer sell the HTX-100 manual but they have it archived and I just downloaded it and printed a copy so I am all set in that department. Thanks for the offer. (I may end up putting it in my truck, not sure at this point.)

Linnea you said you had a 2-meter HT? Is that correct? Can you tell me more?

Thanks! :)

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Post by Lastmartian » 06-25-2003 11:37 AM

I have a 2meter rig as well. I'm using an indoor antenna right now and I could probably hit the Port Townsend repeater but I'm going to throw up an outdoor antenna today. With an outdoor antenna Seattle shouldn't be hard to get and we could probably talk to Linnea.

Ken KD7IZU

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More Radio Stuff

Post by Lastmartian » 07-01-2003 04:18 AM

Just wanted to keep this thread alive.

Linnea, Do you have a 10 meter? I think you mentioned it before. I know Mudwoman has one. It's always worth a try to see if we can make contact on that band.

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Post by Hitchhiker » 07-01-2003 10:32 AM

How about an agreed-upon meeting time and frequency, just to see it we can hit it on 10 meters? Maybe Friday or Saturday.

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Post by Linnea » 07-01-2003 10:35 PM

Hitchhiker - hey, nice to hear from you! Currently I have the 75 meter di-pole which I will be adjusting this weekend. Have to pull it down to attach a support line, ladder line and coax. So far, I am only able to hear as far away as Oregon, Nevada and California. I don't have a tuner yet, so don't know what it can pick up. Really need to get rid of the line losses at this point.

I am working on getting a 10 meter vertical, but don't think I'll have one up by this weekend. Far as I know, Hitchhiker - you, Boomer Geezer, Elk and I have the HF privileges of at least General. Ken will be taking the General on the 12th. Gwen, Juno and Sandy are working on code and General (or equivalent).

Looking forward to QSO-ing with all of you guys! I think Boomer Geezer is still investigating a stealth antenna. Don't know what bands he plans on setting up for. I also have a 40 meter di-pole I have not put up yet. Think I need to figure out where I want to be, and get things configured here. Probably 2, 10, 40 and 75.
Maybe I can shoot for a vertical that can handle 2 through 40, and either keep the 75 di-pole, or when I get a tuner, put up a 65' end fed wire and see what I can tune in.

I'll drop a post here this weekend when I at least get the 75 meter antenna re-rigged. Maybe we could attempt something on 75. Are you set up for 75 meters, Hitchhiker?

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Post by mudwoman » 07-02-2003 01:03 AM

Linnea I have seen many a MFJ VERSA TUNER IIs on eBay. If you stay on it you can probably grab one for anywhere from $50 to 100. They are from what I have read, a good unit. I just checked and eBay has 7 right now (various models) I also have noticed a trend on eBay. Sat. morning seem to be the most popular day for ham equipment listings. Sun is the second most popular day.

Hint: (if you don't know this) Don't do a search if you are looking for a good BIN deal. The search usually lags behind the actual listings. Just zip to ham>new today. By the time a really good deal gets into the search data base it is often sold.




:)

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Tooners

Post by Lastmartian » 07-02-2003 11:01 AM

Hi Linnea, If you buy a tuner on Ebay make sure you know the price of a new one. Go to HRO's or MFJ's site and get the prices. I've seen them sell for too close to the new price, and then there's shipping. At least with a new tuner you know it should be in good shape and there's a warranty.
I also have a gadget called a tuner tuner, it's made by Palomar. It's basically a noise bridge. You tune the receive to the desired frequency, turn on the tuner tuner and it generates static noise. You adjust the tuner until the noise quiets down, and the tuner will be at or very close to resonance. Then you just transmit at low power and touch up the tuning. This takes some of the stress off your transmitter and reduces interference(QRM) that you might cause while tuning . I like this thing because I can spend several minutes trying to tune up, and I don't have to be one of those operators who generate a cw signal for a long time while they fumble with their tuner. The tuner tuner is about $99 new but I bought one on Ebay for around $50.

Happy Shopping!

Ken

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Post by Linnea » 07-05-2003 06:36 PM

Hey, Ken - I am saving my pennies to buy the auto tuner add on for the Icom. Meanwhile - I've got my 75 meter di-pole all taken down and am now trying to get a ladder line installed on it. Seems like a lot of work! Well, better get off the pc and back out into the yard - arrrrrrrrh

{{at least soon I will have an excuse for that ice cold beer... :rolleyes: }}

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