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lgottler
August 30th, 2013, 03:28 PM
I lost my old 48 inch fiberglass antenna and need to buy a new one. Google tells me a 102 inch is awesome. Anyone have any comments on this? Can I arc it from back to front?

For a cb if that wasn't clear.

WhiteRhino
August 30th, 2013, 03:29 PM
Yes you can but it impacts it effectivness. They make great tree snaggers.

fsumotorhead
August 30th, 2013, 04:52 PM
I have one on my rig, it is awesome. Yes it does snag trees, but you can bend it over to the ground without it breaking. The clanging into the truck is the worst offense.

My local radio shack had one in stock for $30-35 when I bought mine.

http://i210.photobucket.com/albums/bb226/fsumotorhead/Bumper%20build/IMG_6335_zps5bd88abc.jpg

kb8ymf
August 31st, 2013, 08:15 AM
I lost my old 48 inch fiberglass antenna and need to buy a new one. Google tells me a 102 inch is awesome. Anyone have any comments on this? Can I arc it from back to front?

For a cb if that wasn't clear.

DON'T do it. Strapping the antenna down and curving it over the truck will make is as effective as a set of Dixie cups. The EMI (Electromagnetic Intereference) with the antenna that close to the body of the vehicle will effectively cancel out most of your transmitted watts. You radio puts out typically 4 watts. The rejected wattage with the antenna near the steel body will suck up probably 90% of that. You'll put out maybe a 0.25 of a watt if you're lucky. Leaving the antenna free to whip around is a huge danger to those around you when you're doing some slow rock crawling stuff.
Antennas like wide open areas around it. Plus that antenna is NOT very forgiving when it comes to tuning it. To tune it you have to cut off the length to get it matched. What happenens if you cut to much off? I'll let you figure that out.

I have a better solution. One I have used for years. And with still only putting out 4 watts, I'll challenge anyone to match the performance of my little radio.
See the link below to what I have. Notice the tuning tip at the top. Completely adjustable up and down. The REAL secret is to tune the antenna to the radio properly. Here's where it gets interesting. Antenna's can only be tuned to ONE frequency or channel optimally. Channels on either side of that channel will degrade further and further SWR wise. Meaning if I tune my radio to a SWR (Standing Wave Ratio) of 1.1:1 on channel, it in theory would be transmitting all 4 of the watts out with nothing being consumed as heat. If you measured the SWR on adjacent channels You will find the SWR gets higher and higher the further you move from your set channel. The problem with a high SWR is that if you put out 4 watts with a high SWR, 3.5 watts of that is being rejected or used to create heat actually and NOT being used to communicate. So pick the channel you want to use most often and tune it to that channel. I wouldn't pick channels near the ends because you will have an extremely high SWR on the far reaching channels. Instead pick something near the middle. Channel 19 or 20 if you have a 40 channel or Channel 11 or 12 if you still have a 23 channel unit.
The other thnig to remember, SWR of greater than 2:1 can be VERY distructive to your radio, Meaning too much output is being turned into heat which in turn can start to heat up the internals of the radio. It's one of the reasons big power radios blow out their final amplifiers because at very high output levels you have to be very careful.

Get this antenna and match it properly and you won't be disappointed.

http://www.k40antennas.com/products/cb-antennas-kitswhips-tips/sp/k40-4-superflex-tunable-fiberglass-cb-whip-antenna-1500-watts-black/

WhiteRhino
August 31st, 2013, 08:31 AM
I've used that K40 and have also had good luck with the Firestick in the same format.
http://www.amazon.com/Firestick-II-feet-Tunable-Tip/dp/B00317HUWU

lgottler
August 31st, 2013, 01:12 PM
I give up. Who sells locally?

Renegade II
August 31st, 2013, 10:08 PM
Wilson tunable tip antennas are usually in stock at the truck stop, exit 144 on the Dixie Hwy in Bridgeport. They usually have them in 3' & 4', super flex and regular. I've been running a 3' super flex on a spring for about 2-3 years now and it's still 1.0:1. Fairly impressive for the beating it takes.

Greenway
September 1st, 2013, 10:08 PM
I have had good experiences dealing with these guys.

cbradiosplus.com (http://www.cbradiosplus.com/default.asp)

lgottler
September 2nd, 2013, 09:44 AM
I have had good experiences dealing with these guys.

cbradiosplus.com (http://www.cbradiosplus.com/default.asp)

I tried to order from them just now and ended up using amazon because shipping was 18 bucks less!

Thanks guys, wanted to touch it in my hands before I bought it, but nothing close enough to me.

Ended up with same stuff I had before, k40 4' fiberglass. Had to buy a new cable too though, looking at the ends revealed broken solder and frayed ground wires all corroded.

lgottler
September 9th, 2013, 06:47 PM
Now, who has a swr meter really close to me?! New Baltimore.

Also, it says to try and mount it away from metal surfaces that are horizontal, like a hood. Can I mount it on an angle and get awesome power from it?

Greenway
September 9th, 2013, 07:03 PM
You want to mount it near a horizontal surface. It acts as the ground plane. Try to avoid vertical surfaces. They make the antenna weirdly directional and can raise your SWR

lgottler
September 9th, 2013, 08:32 PM
You want to mount it near a horizontal surface. It acts as the ground plane. Try to avoid vertical surfaces. They make the antenna weirdly directional and can raise your SWR

Ok, so I had it backwards lol!

Greenway
September 9th, 2013, 09:51 PM
Now, who has a swr meter really close to me?! New Baltimore.



Do you ever make it up around Fenton?

lgottler
September 9th, 2013, 11:03 PM
Do you ever make it up around Fenton?

Everyone seems to live in or near Fenton. Last 4 parts I bought came within 10 miles. Let me try and get my jeep registered and insured again and then I might be up for a trip there!

kb8ymf
September 10th, 2013, 07:11 PM
Everyone seems to live in or near Fenton. Last 4 parts I bought came within 10 miles. Let me try and get my jeep registered and insured again and then I might be up for a trip there!

We can probably tune it pretty quickly if you have everything mounted correctly @ GG in the campground.
j-kb8ymf

WhiteRhino
September 10th, 2013, 08:44 PM
Good cuz my SWR meter died.

lgottler
September 10th, 2013, 09:32 PM
We can probably tune it pretty quickly if you have everything mounted correctly @ GG in the campground.
j-kb8ymf

I didnt want to show up with a non working cb. It picks up the weather band, but didnt try anything else.

Tumbleweed
September 12th, 2013, 11:09 AM
World of CB in Pt. Huron. Very good guy to work with. Know his stuff.

http://www.topix.com/yp/port-huron-mi/l-54327964-world-of-cb

fsumotorhead
September 12th, 2013, 12:36 PM
DON'T do it. Strapping the antenna down and curving it over the truck will make is as effective as a set of Dixie cups. The EMI (Electromagnetic Intereference) with the antenna that close to the body of the vehicle will effectively cancel out most of your transmitted watts. You radio puts out typically 4 watts. The rejected wattage with the antenna near the steel body will suck up probably 90% of that. You'll put out maybe a 0.25 of a watt if you're lucky. Leaving the antenna free to whip around is a huge danger to those around you when you're doing some slow rock crawling stuff.
Antennas like wide open areas around it. Plus that antenna is NOT very forgiving when it comes to tuning it. To tune it you have to cut off the length to get it matched. What happenens if you cut to much off? I'll let you figure that out.

I have a better solution. One I have used for years. And with still only putting out 4 watts, I'll challenge anyone to match the performance of my little radio.
See the link below to what I have. Notice the tuning tip at the top. Completely adjustable up and down. The REAL secret is to tune the antenna to the radio properly. Here's where it gets interesting. Antenna's can only be tuned to ONE frequency or channel optimally. Channels on either side of that channel will degrade further and further SWR wise. Meaning if I tune my radio to a SWR (Standing Wave Ratio) of 1.1:1 on channel, it in theory would be transmitting all 4 of the watts out with nothing being consumed as heat. If you measured the SWR on adjacent channels You will find the SWR gets higher and higher the further you move from your set channel. The problem with a high SWR is that if you put out 4 watts with a high SWR, 3.5 watts of that is being rejected or used to create heat actually and NOT being used to communicate. So pick the channel you want to use most often and tune it to that channel. I wouldn't pick channels near the ends because you will have an extremely high SWR on the far reaching channels. Instead pick something near the middle. Channel 19 or 20 if you have a 40 channel or Channel 11 or 12 if you still have a 23 channel unit.
The other thnig to remember, SWR of greater than 2:1 can be VERY distructive to your radio, Meaning too much output is being turned into heat which in turn can start to heat up the internals of the radio. It's one of the reasons big power radios blow out their final amplifiers because at very high output levels you have to be very careful.

Get this antenna and match it properly and you won't be disappointed.

http://www.k40antennas.com/products/cb-antennas-kitswhips-tips/sp/k40-4-superflex-tunable-fiberglass-cb-whip-antenna-1500-watts-black/

haha, I hope you realized in my pic, that the antenna tuck is only for storage/getting in the garage.