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Base Antenna Coax length,Best Coax and best Antenna under $250.00
- Thread starter Lil'Yeshua
- Start date
Length coax needed
So,at 85%vf, I would need 107.56147 ft. of coax for my base station to antenna project. If I buy the 100ft. of coax with pl-259 ends I could add add the final 7.561477ft. In two jumpers between my RedmansCb modulation meter,swr/power meter and my radio. :blink:
So,at 85%vf, I would need 107.56147 ft. of coax for my base station to antenna project. If I buy the 100ft. of coax with pl-259 ends I could add add the final 7.561477ft. In two jumpers between my RedmansCb modulation meter,swr/power meter and my radio. :blink:
Velocity factor plays no part in what you are doing unless what you are doing has to do with the electrical timing/phasing in some way. What you are wanting to do is simply to use a feed line between the radio and the antenna. Phasing/timing has absolutely nothing to do with it and you have no need for it. That 'KISS' is a very nice and simple thingy to do, so just do it.
- 'Doc
- 'Doc
This question keeps coming up now and then and I just do not understand WHY or WHERE this "I need a certain length of coax" myth ever came from. The ONLY times you need a specific length of coax is when phasing multiple antennas or when using coax to transform impedances. The only proper way to calculate how much coax you need to go from the antenna to the radio is to use a tape measure. No formulas. No charts. No BS.
i used a 102" whip at about 18' high for my base antenna for a couple months and it did just fine for what it was i could get out dx no problem, but i could only do about 1500-2000 miles dx, problem was i couldnt receive from the really far stations. then i got the gainmaster up at the same height and within 30min had a contact in hawaii and the next couple days had ireland, italy and france. also the 102 whip has a lot more static noise than the gainmaster. but it will work fine to get ya going and get you inside instead of sitting in the car all day,lol
remember with the 102 whip you will need the other 1/2 of the antenna, either a few ground plane wires or take another 102 whip and make it into a vertical dipole.
remember with the 102 whip you will need the other 1/2 of the antenna, either a few ground plane wires or take another 102 whip and make it into a vertical dipole.
102"
A base antenna will be installed at some point in time. I got interested in 102" whips with radials for a base antenna out of curiosity and to see what one will do. It's no problem changing out antennas. I made my tower to hinge near the base and I use a 8 pulley rope hoist with the free end of the rope to attach to my toe hook on my SUV to lower and raise it. The tower footing base has a 13 ft. Pole next to it with a braided cable attached to it's top with the other end tied to a 1/4 cu. yd. concrete footing block to brace the pole. The hoist is attached to the pole and to the tower. I'll probably get a Gain Master in a month. Now concerning coax length,everybody always measured their coax in 1/4 wave increments adding up what we needed for a certain length of coax. It was just the way we where taught. I'm getting 100 ft. Of coax and go from there. Thanks for the info.
op:
A base antenna will be installed at some point in time. I got interested in 102" whips with radials for a base antenna out of curiosity and to see what one will do. It's no problem changing out antennas. I made my tower to hinge near the base and I use a 8 pulley rope hoist with the free end of the rope to attach to my toe hook on my SUV to lower and raise it. The tower footing base has a 13 ft. Pole next to it with a braided cable attached to it's top with the other end tied to a 1/4 cu. yd. concrete footing block to brace the pole. The hoist is attached to the pole and to the tower. I'll probably get a Gain Master in a month. Now concerning coax length,everybody always measured their coax in 1/4 wave increments adding up what we needed for a certain length of coax. It was just the way we where taught. I'm getting 100 ft. Of coax and go from there. Thanks for the info.
op:
I do remember that the right coax length was crucial to having a balanced swr reading on channels 1 and 40. P.S. thank you for your answers. That's what I trying to find out if getting the coax length right was the proper way to go. I've read different forums and it seems that nobody could agree on coax length.
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Always measure in 3 ft incrmts, thats what i was told 20 yrs ago. But ive tryied different lengths before and it didnt do anything different. I think you're reading into it too much. As for your mobile whip, it will never perform like an Antron, bottom line, i think we all know that. Matter of fact its the best bang for the buck. The other two i stated might be overkill for many ppl cause A) You're probably never gonna own or run 2,000 watts.....EVER!! B) Maco 5000 5/8 ground plane is way too pricey and just doesnt perform magic like some ppl have said. If you get a A-99 for $50 bucks, you already have one of the best. After that put your $$ in another area of our hobby, radio upgrade, bigger linear, bigger P.S. etc. Just dont throw money at bad ideas, take it down over & over, just trying to help.
Other
I read that the IMAX 2000 outperforms the A99. If I bought either,I would buy the ground planes for them. I looked at a Starduster. They were popular around 1980. Thought about a Maco ground plane antenna. I already have the 102" whip. It's been mounted on the tower mast since 9/11/01. The feed point for this tower for a base loaded vertical is 36 to 37 ft. If I temporarily setup the 102" whip,the twin stacked tv antennas might provide a ground plane. In the Star duster scenario,I would remove the top tv antenna to provide clearance for the SD's radials. With the A99 and the IMAX,I would lower the top tv antenna on the mast. The rotor needs replaced with a heavy duty rotor. It's on it's second rotor now. I suspect that high winds over the years have damaged them both. On the subject of grounding,I need to run a bonding ground cable from the tower's ground rod to the one next to the house where my coax feedthrough is and then run one from there to the service panel ground rod.
I read that the IMAX 2000 outperforms the A99. If I bought either,I would buy the ground planes for them. I looked at a Starduster. They were popular around 1980. Thought about a Maco ground plane antenna. I already have the 102" whip. It's been mounted on the tower mast since 9/11/01. The feed point for this tower for a base loaded vertical is 36 to 37 ft. If I temporarily setup the 102" whip,the twin stacked tv antennas might provide a ground plane. In the Star duster scenario,I would remove the top tv antenna to provide clearance for the SD's radials. With the A99 and the IMAX,I would lower the top tv antenna on the mast. The rotor needs replaced with a heavy duty rotor. It's on it's second rotor now. I suspect that high winds over the years have damaged them both. On the subject of grounding,I need to run a bonding ground cable from the tower's ground rod to the one next to the house where my coax feedthrough is and then run one from there to the service panel ground rod.
id give the 102 a chance for now anyways, you can always upgrade later, at least it will get you on the radio. i just got in from my lunch break talkin on the mobile, wilson 1000 got me to washington, cali, florida, canada from wisconsin no problem, at least got to play for a little while today!