New to Ham, this forum seemed as good as any. ;)

[KK4OYS]

Hi everyone!
I found about this forum from YouTube and joined. I have held a technicians class license since March 2013 but have not been on the air, and do not own any equipment yet. I am a teenager who has always been interested in electronics and have built, hacked, and repaired electronics for as long as I can remember. I also work at a grocery store. As such, my spendable money is very very little after car insurance and gas to get to work I am trying to get into Ham as cheaply as possible and was looking for advice, I was looking into a Baofeng BF F8 as my first radio, it is the updated version of the popular UV-5R. As it is cheap, and will still be useful to have a HT once I get a "real" radio. I would like to make my own antenna that I could connect it to when at home, and have about 80 ft in the air.

So, could anyone recommend some antenna designs? Also I have lots of standard TV Coax, would that be acceptable to use as the connecting line, as 100 ft of "ham radio coax" with the SMA connector is $80! I can easily install SMA connectors on my own Coax if that would work.

Do I need a SWR meter and antenna tuner right away when trying to make my own antenna? Would it even matter at this low of wattage? (5W)

I have heard of people running the Baofeng through a amplifier, and have seen some fairly cheap ones, would that seem like a logical upgrade I could make after a while?

Thanks for listening.
Jonathan
KK4OYS

 

[KC9Q]

Welcome Jonathon,

You're on the right track getting the portable and making your own antenna. You can add a dual band amplifier later. Probably the easiest antenna you can build is a ground plane. Using the formula 234/F(MHz) will give you a good starting point for the radiator. Add 5% (1.05 x (234/F(MHz)) for the length of the radials. Mount all parts to a SO-239 UHF Chassis Mount Connector. Use #12 solid copper wire for your elements. Bend the radials down at a 45 degree angle to get a better match to 50 ohms. Two hints: 1 - Since you are likely to operate more in the FM band design the antenna somewhere between 146 and 147 MHz, 2 - The third harmonic of 2 meters (147 MHz for example) will place you in the UHF Ham Band (146 x 3 = 441).

Yes, it would be helpful to have a VHF/UHF SWR meter or antenna analyzer, but at 5 watts the formula above will likely give you a workable antenna. For coax I would suggests a minimum of RG-8/X cable. UHF is you limiting factor since it will have the largest line loss in this system.

Welcome, enjoy the forum, ask questions, learn, and most importantly have fun.

73,
Mike, KC9Q

 

[Tallman]

There are lots of sources to come up with inexpensive equipment. Craigslist can some times yield good bargains but beware there is junk out there for sale too. The swap meets at the ARRL hamventions can be a good way too. The best luck I have had is the estate sales and eBay. Ebay has been the most reliable so far because I will only buy from sellers that use PayPal. Buyer protection is wonderful way be sure you get what is advertised.

 

[KK4OYS]

Welcome Jonathon,

You're on the right track getting the portable and making your own antenna. You can add a dual band amplifier later. Probably the easiest antenna you can build is a ground plane. Using the formula 234/F(MHz) will give you a good starting point for the radiator. Add 5% (1.05 x (234/F(MHz)) for the length of the radials. Mount all parts to a SO-239 UHF Chassis Mount Connector. Use #12 solid copper wire for your elements. Bend the radials down at a 45 degree angle to get a better match to 50 ohms. Two hints: 1 - Since you are likely to operate more in the FM band design the antenna somewhere between 146 and 147 MHz, 2 - The third harmonic of 2 meters (147 MHz for example) will place you in the UHF Ham Band (146 x 3 = 441).

Yes, it would be helpful to have a VHF/UHF SWR meter or antenna analyzer, but at 5 watts the formula above will likely give you a workable antenna. For coax I would suggests a minimum of RG-8/X cable. UHF is you limiting factor since it will have the largest line loss in this system.

Welcome, enjoy the forum, ask questions, learn, and most importantly have fun.

73,
Mike, KC9Q

Thanks for the info!
I was hoping I was on the right track. Now a question is the SO-239 connector the same they use for CB, from the picture on amazon it looks like one. I have a whole box of CB connectors and stuff, a friend gave me. I also got an old 10W CB I thought about getting a frequency counter and messing around with that, although I don't know if I could change its frequency enough to get it into a band I can operate in.

Since you are likely to operate more in the FM band design the antenna somewhere between 146 and 147 MHz, 2 - The third harmonic of 2 meters (147 MHz for example) will place you in the UHF Ham Band (146 x 3 = 441).

Is this why 2M antennas are good for 70CM too?
And excuse me for the noob question but what do you mean by FM band, I thought all ham bands where Frequency Modulated? I shouldn't have watied so long since getting my lisence, I have forgotten stuff, I should have got the little Baofeng right away and learned.

I have an old (80s) VHF Radio Shack project kit I found unused at a yard sale and built when I was about 12. I recently pulled it out again, and found it is 108-170 MHz and was able to pick up some 2M Morse code. Now I want to learn Morse code!

 

[Dipole]

Good luck with the BF-F8+ I had one delivered on Monday and It went back today I put it on My base antenna at 40 ft and could not hit a repeater that is 12 mi away I was however able to hit it when I could see the top 1/3 of the tower by eye at about 1 mi. Might have just been that radio. Anyway the Hobby need more young men like you welcome to the forum, 73's from KF5AQH

 

[KK4OYS]

Good luck with the BF-F8+ I had one delivered on Monday and It went back today I put it on My base antenna at 40 ft and could not hit a repeater that is 12 mi away I was however able to hit it when I could see the top 1/3 of the tower by eye at about 1 mi. Might have just been that radio. Anyway the Hobby need more young men like you welcome to the forum, 73's from KF5AQH

I was wondering about the Bf-f8 its supposed to just be an updated uv-5r but its pretty new and I couldn't find very many reviews. I wanted the extra watt, which is the biggest new feature, besides a supposedly better speaker/mic amp and other random improvements.
Did yours have the white on black screen? there is a version two that went back to the normal screen and as they revised the screen there may be other fixes. Does Baofeng release firmware updates that you can install over the usb cable?

 

[vkrules]

Try this antenna design. http://vk2zoi.com/articles/half-wave-flower-pot/ easy to make out of coax. Has a lot of high gain and dual band variations . VK2ZOI s page is well worth a look.The 75 ohm TV coax is less than ideal but will work.Some of the quad shield pay tv cable is actually fairly low loss and this design comes out at about 60 ohms anyway. No you can't upgrade the firmware on the Baofeng . I've owned a uv-5rb for three years now and still going strong except that the battery life is a little lower than it used to be. They do suffer from poor selectivity however, so if you have high power pagers in your area fitting an external antenna is not advisable.

 

[KK4OYS]

They do suffer from poor selectivity however, so if you have high power pagers in your area fitting an external antenna is not advisable.

Nice antenna idea.
By poor selectivity do you mean where they go into overload shutdown when they are to close to a high power output? I've hear the uv-5r does that if to close to a high powered ham rig.
The repeater I would be trying to hit is about 20 miles. I know that's hard for an ht but I can get my antenna up to about 80ft which is a good 15ft higher than all surrounding trees. I live in Florida, so its pretty flat but I do live on the top of the tallest "hill" in my county.

 

[w9cll]

What he means is they will pick up everything in an high RF area like a bigger city. Here in Chicago my uv-5r is fine out in the burbs where I live but in the City it's just about useless because of all the RF it's picking up.

 

[vkrules]

just made up the dual band version took about 15 mins to construct works well. Just a note though if your 75 ohm cable has foam dielectric add 30mm per side to allow for the higher velocity factor. IE 487 and 477

 

[KK4OYS]

just made up the dual band version took about 15 mins to construct works well. Just a note though if your 75 ohm cable has foam dielectric add 30mm per side to allow for the higher velocity factor. IE 487 and 477

Awesome, this will be my first home antenna for sure.
My coax is plastic core.
Also, does the whole assembly go in the pipe, the coil and all? Because it looks like the coil is outside the pipe. I would like to put the whole thing in a pipe and put a cap on both ends so I can drag it to the top of the tree with a rope.

As for selectivity, I shouldn't have any problems I live over an hour from any big cities (Jacksonville, Gainseville, Tallahassee, and Valdosta).

 

[vkrules]

OK use the original measurements. I built the dual band version with the sleeve over the center. No the coil is wound over the tube.( standard electrical conduit)you will still be able to pull it all up a tree. I got 1.2 to 1 vswr on 438 mhz and 1.3 on 146.5 with a random length of foam dielectric tv 75 ohm cable .Sitting inside my shack it out performed the original Antenna dramatically . It's good to go.I will make another with 50 ohm cable to make sure the results are repeatable I also like the high gain colinear dual band version.!

 

[vkrules]

 

[w9cll]

Think I am going to make one of these just for fun.

 

[KK4OYS]

I am going to make one of these when I get my radio in, but I have a few misunderstandings, does the pipe have 2 holes drilled in it and the wire comes up inside, goes outside for the coil then goes back inside for the rest of the antenna?
Also are you stripping the parts that say coax inner down to the copper or is that copper + plastic insulation, just remove outer plastic and shield?

And you pretty much lost me with the double segment one. What are the sleeves for? Are they supposed to be metal so as to block RF?

Thank you guys for all the ideas!