Query about hf Mobile Antenna
I am looking to purchase a good mobile antenna for 40, 20, and 75 meters. I know that there are a lot of screwdriver type antenna's available. But please my wife ( she things they are ugly), what would be the best one that could be trunk lip mounted, and not cost an arm and a leg.
Most cost $400-600 and only provide 3-5% efficiency at best on HF. So you can use your 100w rig to put out maybe 5 watts of mobile power!!
Its called GLOBAL WARMING using these things! Check the ARRL archieve search on mobile antenna, back in 2007 or so they did a comparison of 5 moible antennas most screwdriver types with the best doing less then 5% efficiency.
For a start, forget about 75-80 metres, a poor band for mobile operating 100 watts in and radiate about 3 watts. Buy a Hustler, years of reliability and you can remove the mast from the car in seconds
Different take on this:
Other than die-hard mobile lunatics (!), for many years almost all mobile HF operators used very inefficient antenna systems and had fun and made contacts, anyway. Nowadays the best (largest) "screwdriver" antennas mounted in the best possible ways are substantially more efficient than what most of us used 40 years ago, but we still had fun and made contacts.
So, I wouldn't sweat the small stuff unless your life revolves around it somehow.
A Hamstick on a trunk lip mount will make lots of contacts for a total of about $50 invested (for the first band) and then another $30 or so per-band extra. It's not automatic, and you will have to stop the car and get out to change bands; but it's cheap, it works, and you'll make contacts.
75m is about the worst band for this, though. I'd stick with 40m, 20m, 17m and above.
Get a strong trunk lip mount, spend a few extra bucks there. Make sure it has good electrical contact to the trunk, and run some extra ground straps around the trunk lid hinges to bond it well to the body of the vehicle. A bit of extra work, but almost zero extra cost, and it can help.
A government which robs Peter to pay Paul can always depend on the support of Paul.
-- George Bernard Shaw
Where do you get that rubbish from? On 10m they're not far off the size of a quarterwave. On 20m they'll still be several times your claim. On 80m they'll be worse.
Originally Posted by KD5SPX
I would betcha on that one! Antenna "shootouts" have proven the screwdriver to be superior to the Hustlers---especially on the 75-40 meter bands. None of the known mobile antennas give equivilent efficiency to a dipole or "V" high in the air, for several reasons, but the screwdrivers come the closest to giving reliable and regular contacts on these bands. It is rare for someone not to be able to hear my mobile station, and if I add the "heat" (750 watts), it comes close to a 100 watt mobile in signal reports.
Originally Posted by G0GQK
Hamsticks are CHEAP and work surprizingly well. Not anywhere near as good as Screwdrivers, but they are very light and easily removable or interchangable. Thats what I run on my trunklip mounts.
I mostly agree. I now use a Bugcatcher; it is quite efficient as mobile antennas go, and easy to remove and store with quick-disconnects. But I started out with hamsticks and had a lot of fun. With quick-disconnects, and a set of antennas for your chosen bands, you can change bands very rapidly. On 20 meters and above, they will work quite decently; 40 is so-so; 75, almost pointless if you don't have friends listening for you.
Originally Posted by WB2WIK
If you use a trunk lip mount, get the very best one you can find - at minimum a K-400. After mobiling for a while, if you want to take a BIG step forward, drill and put in a ball mount - I recommend Breedlove. If you do this, on 15m and above you will be competitive with almost all other mobiles, even with a hamstick. Until then, do ground the trunk lid with nice wide straps,
And have fun!
i got both a big screw driver antenna,from larry's antenna and a little tarheal antenna both work great I also have ham sticks and they do just fine I have been happy with them. I used ham sticks on my way back from Dayton last year when I drove and they did just fine. the problem with ham sticks you have to change the antenna every time you change bands
Born to be Wild
Well, I was thrilled with my big Tarheel for a while. Then, one day, I went to use it, and I couldn't get a good match with it. Last week, I replaced the ground strap I used initially and that fixed the issue. But I noticed that I had some kind of inermittent in it. I couldn't pursue it immediately, though.
I have to make an urgent trip to California, followed by a rush trip to Florida. This morning, I discovered that the Tarheel wouldn't tune. The screwdriver works and the antenna moves up and down, but there is no indication of resonance. My antenna analyzer shows a resonance at about 35 MHz! So, not having time to investigate, I threw my old Hamsticks and Hustlers back on the truck and headed out. The big Tarheel works much better than a Hamstick on 20, but at least the Hamstick works.
I am hoping it's not really the antenna and maybe my feedline is bad. I'll find out when I get to a stopping place. But if it is the antenna, I am not a happy camper. Until this stuff started, I was really impressed at it's performance, and ease of use.
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