Garmin Question for Steve White or Whoever can Awnser it

[doghunter]

Mr. White In past post you seem to know a lot about Frequency’s, Line of Site, ETC. I use the Roof Mount Magnet antenna from Garmin and it about doubles my distance (out to about 2 miles). If I can keep that I am happy but;

1. Isn’t the antenna I use a ¼ wave link antenna.

2. If I use a full wave link antenna would it increase my range or read the digital signal better if weak providing both are the same height.(I know higher is better)
3. Can I use a marine radio antenna like the offshore boats have (like sold in cabalas or boaters world if I put a connector on that will fit the Garmin.
4. And last what antenna would you suggest improving range and reception over the roof mount antenna I currently use.
5. if I purchase an antenna would I have to cut it to the proper length to match the wavelength and where would I find the info on how long to cut it.

Thanks any help would be appreciated. I have compared the extendable antenna from Garmin and it is about the same as the roof mounted I use. (Most of my tracking is done from the truck).

Hound hunters are the most ingenuitive group out there does anyone have any input on this I cant believe someone has not tried this yet and can comment.

Here is a link for an antenna i am thinking about trying or if no one can help i may try the marine radio 8' boat antenna mounted on my bumper http://www.dpdproductions.com/page_murs.html

here is another link that give some info on range of the Garmin (murs) http://www.buytwowayradios.com/blog/200 ... d_vhf.aspx

and this link i had to add because it is on the topic of frequency and it is very informative but it also is just like alot of our threads with getting off topic and upset. you ever wander what a nerd blogs about just check it out. but again very informative and they say line of site is always exceeded. http://forums.qrz.com/showthread.php?t=181314

[Jason Waterhouse]

Thanks for posting these questions dog hunter. Im looking forward to the answers also.

[doghunter]

I cant beleive no one has tried anything other then the garmin antennas. I am trying to find out what i should start with and I would like to use the marine raido antennas for boating. if i cant get any info i will buy one and report back

[Copper]

I don't believe the garmin transmits on the MURS so the antenna doesn't have to be perfect like it does when you transmit. So you could buy or build any type of antenna that you want if you want to get a better signal then build a antenna that has a lot of gain such as a yagi or any other type of directional antenna although it would suck to have to keep aiming it in the right direction. A full wave antenna for 151 MHZ would be pretty big you might want to do a half wave first.

Yes you could use a marine radio antenna not sure what frequency they use but the further away the frequency that the antenna was built for is from the desired frequency will depend on how well it will work.

[doghunter]

Thank you for your response. I know very little about all this stuff but I am trying to learn to better my equipment.

Garmin uses the freq. 151.82MHz, 151.88MHz, 151.94MHz, 154.57MHz, and 154.60MHz

The following are the frequencies authorized for use by the MURS:
Frequency Authorized Bandwidth
151.820 MHz 11.25 kHz
151.880 MHz 11.25 kHz
151.940 MHz 11.25 kHz
154.570 MHz (also part of business band) 20.00 kHz
154.600 MHz (also part of business band) 20.00 kHz

These are public Frequency's and that fit by definition the way Garmin uses them. That is why they did not have to get a license to use them and why a lot of people are having trouble with other legal units interfering or damaging them. Here is a link that backs up the MURS bands I listed. http://www.buytwowayradios.com/blog/200 ... d_vhf.aspx

And you can look at the Garmin owner’s manual to confirm the frequency I gave for the Garmin are correct. (At least it is listed in the older manuals)

I have seen Motorola antennas(MURS) that don’t appear to be much longer than the ones Garmin sells. From what i can find it appears the Marine Frequency’s are between 156.??? and 162.??? I am not sure if this is close enough the receive the Garmin on the MURS band or not. Here is a link to confirm the Freq. http://www.navcen.uscg.gov/marcomms/vhf.htm

Most hunters that use a CB radio use a 102” whip antenna I would not think a full wave length MURS antenna would be any longer than that, but I don’t know for sure or if it would help any.

If anyone know the answers please respond if we can find a better antenna that will increase our range then we will all be better off.

I wonder if we will be able to connect an exterior antenna to the Marshall.

[Copper]

A full wave antenna at 151 M hz would be at least six feet in length and it wouldn't be a huge improvement over a half wave that would be around 3 feet in length. A marine antenna that is built for 156 M would work but you would have some loss compared to a antenna thats built for 151 MHZ.

[PLOTT88]

I have used my truck mount antenna for my VHF radio on my garmin and it works it is about 3 ft in length. Seemed to work near as good as the Garmin long range antenna.

[tman308]

Just what I know,

You can't use a CB antennae for the Garmin because the frequency is too low. It will improve overall reception but won't give you the desired results. The best thing that you can do is get on a Ham radio site and buy a high gain antennae that is designed for the 155 band. This will give you the best overall performance. I used to have an antennae on my vehicle that was tuned to 155 and programmed the Murs frequencies into the radio. The radio had a watt meter on it and I utilized this to get close to the dogs. I could pick up the beeps from the collars on the truck radio for a long ways before my Garmin started picking it up. The truck would start picking up at around 10-15 miles depending on terrain. The garmin I have has a high gain antennae on it that I purchased from a Ham supply store. It will pick up on average out to 5 miles I have seen it pick up further and I have seen less. It mostly depends on your relative location and the location of the collar. If you are in a canyon and the dog is over the ridge you won't pick them up. When I am looking for dogs I just get some elevation and start from there. The other thing you can use on your truck is an attachment sold at most CB supply stores that looks like a star. It makes your vehicle a better plane for receiving radio signals.


Hope some of this helps

[doghunter]

Thanks for the info everyone.

I have been reading some of the Ham radio sites and they really understand this stuff. but it is a bit over my head. they have a base antenna called a fire stick and i may try. Firestik has a center frequency of 153.210MHz which is right in the middle of 2 of the MURS bands. take the speed of light (982,000,000 feet/sec) and divide it by the center of the operating frequency which is 153,210,000 and the result is r 76.5 inches for a full wave. or if the operating frequency is 154.570MHz, this means a full wavelength is 76 inches. you can check out the fire stick at this link http://www.firestik.com/CatalogFrame.htm.

I just have to figuare how to hook it up to my truck I am also checking out some better antennas for the collar. Has anyone tried to put a better antenna on the collar.

tman308 do you know of any Ham stores online i could check out or could you tell me where you got your antenna.

[doghunter]

I am going to try one of these two antennas today I will let you know if there is an improvment.

1. http://www.truckers-store.com/store/sho ... 2040814086

2. http://www.dpdproductions.com/page_murs ... rsmobile58

Anyone got any tips on which one to start with.

Also anyone know of a better antenna we can put on the DC 30

[not color blind]

doghunter, for getting the longest range I use a directional yagi for the 150-155 frequency(beep-beep antenna). But like Copper said it is a little bit of a pain getting it out and pointing it in there direction (but most should be used to that we have been doing it for years with the beep beep ). I don't have to use it very often but it gives me AT LEAST 2 or 3 times the range of the roof mount.

[tman308]

doghunter,

aesham.com is the website for Ham radio and other supplies.

Vertex Standard USA
Attn: Amateur Repair
10900 Walker Street
Cypress, CA 90630
For Technical Support or Customer Service call, (714)827-7600 between 8AM – 5PM PST

Vertex is where I got the antennae for the DC-30. You just tell them that you want a high gain antenna for a vertex 150 (handheld radio) it is tuned to the 150-160 band. It's only about 12 inches long so it's easy to pack around on foot or horse. It screws right on to the garmin no other attachments needed.

[houndcrazy93]

doghunter have you tried any of the two anteneas that upu mention yet. because i just have the garmin unit, and i want to get a better one. so will you just let me, and the rest of us know how they worked out if you tried it thanks

[doghunter]

I have both ordered. I will let you know when they come in. i went through a local dealer and it is taking kinda long to get here T

They install all the radios in the police cars and other buisness owners that use them in my area. he said he was impressed we could get 2 miles out of a 2 watt transmitter so low to the ground.

We talked about increasing the watts on the collar but he said even if the unit could take it, it would cause so much heat it would greatly reduce the life of the collar.

He also said he beleives the front end of the antenna is what is being damaged with the raido use and said it does not have to be the same frequency to damage the unit. any radio even a cb if pushing enough power to jamb siginal into the garmin at close range could burn up the garmin. just his 2 cent as someone that installs and repairs radios on the MURS band.

I ask everytime i send my unit back for them to tell what is being broken but i still havent gotten a good awnser from garmin or from someone that could make me understand exactly what is going on.

I also found a guy on another site that claims "I make a long range aerial for the dc30 which here is only about 25% better overall coverage not alot but still very handy especially with deep gullies/creeks or drop offs.where they excell" here is a link to the site. http://67.20.89.228/boar_hunts_forum/vi ... f=1&t=8713

I just am not sure about buying something from overseas. anyone hear of someone in the states doing this. I can remember putting them on the dc20. but not sure if they would heip on the dc30

[houndcrazy93]

hey doghunter do them antenas work for the garmin?