VHF UHF antenna basics - DIY antennas from surplus 800mhz antennas for 2m 70cm and dual band

Video on repurposing surplus 800mhz 5/8 wave antennas to VHF and UHF. These antennas have little resale value and as such are ready candidates for experimentation at extremely low cost. Build it yourself , save money, and learn as you go.

[@pirateradiooffroad2460]

I came here looking for "antenna basics", and ended up walking into a university science lab. I was ok at first, i just played it cool and sat down and listened. Yup antennas. Ahh cool, an old cell phone antenna. Ripping apart old cell phone antenna. Yup. I got this. THEN....outta no where comes the, the, the thing-a-mometer xj 6000 analizer. I know im already in over my head. Maybe i can bluff my way through this....be cool. Ok. You got this....

[@pirateradiooffroad2460]

I went back and watched it from the start. Good vid. Thanks for the info.

[@survivalcomms]

Thank you ! That's an old video - I have upgraded to an Anritsu CellMaster for antenna testing now that they are being surplused out so cheap . I'm glad you enjoyed the video. Antenna scrapping can be fun . Thanks for watching !

[@acestudioscouk-Ace-G0ACE]

A great piece of repurposing, works well too!

[@survivalcomms]

Indeed it does ! Thank you and thanks for watching !

[@GreekPreparedness]

man you saved me mone,y and gave me a good project to work on. I have a mobile antenna cut to the Airband which now I can fix. TNX and 73s!

[@survivalcomms]

Cool beans ! Let me know how it works out ! Thanks for watching !

[@Stingmni]

Thank you for this. I did tye the same using old mag mounts for commercial band. I straightened some coated wire from a fence and cut off pieces at 1/8 inch each time, watching the results.

[@survivalcomms]

Cool ! It is always fun to make something useful. Thanks for watching !

[@faditech6793]

Amazing ! Very Helpful and excellent explanation.

[@survivalcomms]

Thank you ! I am glad you enjoyed it. Thanks for watching !

[@faditech6793]

You get my full respect, whenever there is a "Coil", a rule of thumb is "Trial and error", coils have very tedious and complicated formulas that takes lots of calculation and end up useless. You did a great job by kicking computing off the table. Saved us time & money and most important it works PERFECTLY !!!

[@survivalcomms]

I played around with what I had laying around at the time. I had lots of 5/8 800 antennas at the time. Since on the VHF side it was just a quarterwave it was pretty simple. Thanks again !

[@RustyOrange71]

A tap and die set is a really useful tool to have. Paired with a box of different size grub and steel machine screws you'll find lots of uses for it.

[@survivalcomms]

I have a nice set here. The whip was much smaller than the stand off. Would have had to seal it regardless. 5 + years later it's still working good. Thanks for watching !

[@dc5833]

Great job. Well done. Again.

[@survivalcomms]

Thank you and thanks for sharing !

[@sudviatradersandco5248]

Hi there!. Many thanks for this very useful video. I´ll tried this with my Motorola DGM8500, and work perfect. The radio model it is for Latin America, so for your area I think it is XPR. This is Chile, South America.Greetings!

[@survivalcomms]

I'm glad it helped you out. Thank you for watching !

[@jamescopeland5358]

Thx a lot that just taught me something

[@survivalcomms]

You are welcome ! Thanks for watching !

[@RobPainless]

Cool stuff. I still have a long way to go.

[@survivalcomms]

Thanks for watching !

[@2009KVFD976]

Can something like this be made in a 5/8 wave for VHF and UHF base station? 95% of the time it will be listening but I will mainly transmit on 146, 154, 451 and 458MHz. Thanks for the awesome video! I'm using a tram 1181 on a ground plane base and it does well for my use. But I'm wanting more gain in the UHF side as it lacks a bit. SWR is about perfect with this setup but would like to try a 5/8 wave and see if it helps any.

[@survivalcomms]

You should look into building a collinear antenna for UHF or a yagi and away from a "dual band " solution IMHO. This is a resonant compromise. Thanks for watching !

[@donarnold8268]

Thank you!

[@survivalcomms]

You are welcome ! Thank you and thanks for watching !

[@dennisweisenreider7314]

Great video. Thanks. Can radials be added to the base if not used with a mag mount? Thanks D

[@survivalcomms]

Thank you ! Yes they can . Placing the nmo base on a sheet of metal with radials or using a commercial kit such as the Larsen BSA KIT (Tessco PN 38748) can adapt mobile antennas to fixed applications. Antennas adapted thus exhibit the same characteristics as they would mount on a vehicle. Thanks for watching !

[@joeschnell544]

Hey don’t forget the ferrule the whip gets inserted to also counts as part of the whip itself.

[@survivalcomms]

Yes indeed it is conductive. Thanks for watching !

[@tomw5vlt119]

Thanks. Wish you’d shown how u were testing the antennas, for beginners, don’t know how you connected them to antenna analyzer... only seen them hooked up to coax.

[@survivalcomms]

Back when I made this video I was using my buddy's MFJ 259. I try to keep my videos short and sometimes details get left out. The feedline connects from the antenna's NMO base and goes the the RF connector on the 259 in this example. I use an Anritsu Cellmaster now for VHF/UHF/SHF antennas and the antenna connection is on the RF out on that one. I hope this answers your question and thanks for watching !

[@Aaron48219]

Thanks. Question (since I'm not good at coils)...would it be possible to make a 1/4w vhf and 5/8w uhf with these? Gonna make me some dual band MURS/GMRS antennas for the cars and HTs.

[@survivalcomms]

With old 800 antennas it wouldn't work out. It is possible with other antenna designs. If you want good performance go with monoband antennas IMHO. Thanks for watching !

[@gregbeyer3904]

Thank you, very interesting video, and I like homebrewing with what I have at hand. It seems you have identified the length of an 800mhz resonator which works on VHS simply by finding that the elevated feed resonator on the low mount has proper SWR - so, luck? Knowing the length of the long resonator, you built the other resonator up, and created other variations. But -- what length, in inches/cm, of a 800mhz resonator are we wanting to find or build? They come in at least two lengths, maybe more? I didn't hear in the video any length -- only lengths of segments relative to parts of the long resonator. Thanks for clarifying.

[@survivalcomms]

5/8 wave 800mhz antennas were all the rage in the smartzone and amps days and every one I have found will work if you extend the resonator as shown. Just find a 5/8 wave 800mhz (806-870) antenna and add length. These antennas pulled out of the pile unmodified are typically resonant around 160-170mhz just add a couple inches overall and your VHF is done. Thanks for watching

[@chrissewell1608]

I was recently gifted a hand full of old ham radio antennas, and odd radio stuff & junk. One was a mag mount (odd sized) dual band antenna, which now appears to be a cell phone antenna! (Its crap on 2 meters!) So I will try and convert it into a 2M/440 or something usable? Great video and explanations!

[@survivalcomms]

The 5/8 wave cell antennas are resonant about 160 + - 5mhz in my experience. If you remove the finish , put a test clip on the top, and add a couple inches of wire adding length above the coil you can see if it helps. Thanks for watching !

[@stewartrv]

I wonder if you can get you hands on some stainless steel welding rod and use that to make your own elements - the only issue will be making the little thing on the end but I guess another coupler could be used instead. I think they can be a cheap source for these, not sure what the max length is.

[@survivalcomms]

Those will work. I have access to the rods. I just used the pile of surplus antennas I had to make the video. Thanks for watching !

[@TaitGuy]

Very Nice, thank you! Question regarding the dual-band antenna. I noticed you put the UHF antenna closer to the base and then worked with the two meters at the top. Does it matter? Thanks again! Good info!!!

[@survivalcomms]

You are welcome ! I wanted the UHF length before the coil. I have not tried it the other way to see if it would work. BTW I still use this antenna on a mag mount when I use a rental car. Thanks for watching !

[@jotinnalynmabolo3077]

were we can buy the materials

[@superaprendendoacozinhar]

Explain the following to readers. It's 6 inches before the load coil that is this loop, and after the loop it's 8 inches. This loop of 8 turns makes the resonance at what length ? This loop has 2/4 wave, that is, half wave ? The antenna has 2 radiant and if we want to put more radiant it should repeat that same amount of coil + radiant? Because there are no new videos about these collinear antennas for VHF and UHF on your youtube channel.

[@SuAmigoElilegal]

Sir I got a radio UHF car mount antenna for my radio. I just recently got a dual vhf/uhf baofeng . Can I use that same antenna for my baofeng dual radio . Now the whip rod on the uhf antenna is removable and is about 9 inch

[@survivalcomms]

Yes you can as long as you keep the antenna parameters within the VHF / UHF frequencies you wish to cover. Thanks for watching !

[@esmaeil_smile]

great thanks

[@syspangylium]

I haven't done any antenna fiddling before so I wonder if I can solder a resonator to the center of a pl259 plug? If so, what do I do about the outer part of the plug? I assume I have to isolate it from the resonator so it doesn't short out. Or am I totally lost in the woods and it can't be done this way?

[@survivalcomms]

You can totally make your own antenna in that fashion. You will need a resonator that you can solder , solder it to the center pin, insure that your resonator is insulated from the body of the connector. Thanks for watching !

[@syspangylium]

@@survivalcomms Thanks! Any particular material I should use or is it good enough as long as it is insulated and the plug is filled up for sturdiness? Edit: Could I use the dielectricum in a coax cable and slip it on the resonator? If it's too tight I could split it and insert a strip of dielectricum in the split and fill up excessive space in the plug with non conductive silicon that hardens, for sturdiness and to prevent water to enter. I will have to find a resonator that will not bend easily and still fit the plug because I'm planning to put it on a magnetic base and use it on my car. It will not be for the ham bands. It will be for commercial frequencies in the ranges 154-160 MHz and 445-460 MHz. I will start with the measures from your videos and experiment from there, shorten it bit by bit. Do you think it's possible to make the antenna resonate in both the above mentioned frequency ranges? Any other comments on my plan? I can use all the advice I can get.

[@survivalcomms]

@@syspangylium some dielectric from RG8 should suffice

[@syspangylium]

@@survivalcomms Thanks again! ☺️

[@survivalcomms]

You are welcome !

[@jotinnalynmabolo3077]

what is the measurement

[@lawrence1md]

Have you tried stacking 2 5/8 or 2 1/4 waves? (Colinear)

[@survivalcomms]

I haven't as I was interested in keeping a compact profile but others have done it . I did have the hustler colinear 2m one 28 years ago and it was legit perfomance wise but enormous. Thanks for watching !

[@lawrence1md]

@@survivalcomms I can imagine it was long….

[@survivalcomms]

@@lawrence1md It is still available www.hamradio.com/detail.cfm?pid=H0-003363

[@williampriest2224]

What kind of Mount are you using?

[@survivalcomms]

NMO mount Thanks for watching !

[@jloaiza9188]

Why are 1/2 wave gmrs antennas longer than 6” like the the laird 12.5 ?

[@survivalcomms]

That is because it is a half wave radiator and not a quarter wave radiator. Thanks for watching

[@sebastiantufigno6955]

Would it do any difference if you use same antenna like these if I use on 5w handheld or 25w base in car ?

[@survivalcomms]

Sebastian Tufigno No difference at all. If you have a solid connection you are good to go. Thanks for watching !

[@MSgt101]

Odd question. If you can make another UHF band for GMRS can i buy it off of you? I have been looking for a cheaper alternative to paying $47 I also have an old CB antenna if you can make a video on how to cut that down... its a cheap schochi from walmart

[@survivalcomms]

There are lots of cheap UHF antennas out there. Which one is 47 bucks ? You can make a UHF quarter wave out of that scosche cb antenna pretty easily.

[@MSgt101]

Is there any way you could make a video explaining how to make one? and I was talking for the magnetic base and the antenna whip itself

[@survivalcomms]

MSgt101 spin the spring off of the base and let me know what size the post is .

[@MSgt101]

It doesnt sat what size it is but it is the same size on bothe ends and i only have the antenna not the base

[@survivalcomms]

so you have no magnet or feedline ?

[@esmaeil_smile]

i wana make an L_ROD metal detector please help me...tnx

[@ciedrickdorilag3626]

what metal is that sir

[@aasdarwati6151]

Can use this antenna for freq 138-176 Mhz and 400-520 Mhz?

[@survivalcomms]

You could but it would not be completely efficient across that range. Thanks for watching !

[@rickymcdaniel6708]

I want to see a UHF GMRS antenna mod.

[@survivalcomms]

It you have close to 6 inches above the coil you are good cutting that off and using it as a 1/4 wave resonator on GMRS. Thanks for watching !

[@Johnysoutherner]

Could you give me an idea of what size dc couplers you used here?

[@survivalcomms]

The motor couplers were 3mm Thanks for watching !

[@Johnysoutherner]

Thank you for the fast response, 73 from KK4PGM

[@Ibelieve218]

lets see if I get this right you take the length of the vhf and add the length of the uhf to get dual band antenna

[@survivalcomms]

The length beneath the loading coil will dictate your UHF resonance. The overall length will dictate the VHF. Do you have an old 5/8 800 mhz antenna you are working with ?

[@Ibelieve218]

@@survivalcommso was thinking of buying some on ebay. just needed more understanding s othe rule is the bottom half is the uhf and the overall is the vhf .I want to get into understanding antennas during and emergency and you have to vacate be nice to know what you could use to get by with for antenna

[@survivalcomms]

The 800 5/8 waves can be pressed into service as VHF quarter waves if need be as is. In this circumstance the main consideration is to keep the length of the UHF at 1/4 wavelength below the loading coil. The overall length should equate to a 1/4 wavelength at VHF. The best practice is to test what you have to see where you are before you start cutting. You can always lop off 6 inches above the coil remove the coil and make a UHF antenna.

[@superaprendendoacozinhar]

@@survivalcomms SurvivalComms explain the following to see if we understand 100%. If we put 6 inches or 1/4 of a wave into UHF we will have, for example, an antenna for the UHF resonator down below the charge coil. Now above the charge coil will have another 6 inch or 1/4 wave UHF resonator with the same measurement, okay?! Now what is the measure of this turn that lies in the middle of these two UHF resonators? What happens if this coil is larger or smaller in turns, and in turn the more coil (the coil) increases in size and the less the coil the smaller the coil. We want to understand the following: 1/4 wave of resonator at the base just after the magnetic base and before the charge coil, then the charge coil, after the charge coil another 1/4 wave resonator, is this? What is the purpose of the load coil because it is not responsible if the antenna will cover 1/4 wave in vhf. If 1/4 wave is used above and below the load coil, what is the purpose of the load coil? You can explain it better. Because we like antennas and understand how we can improve our own antennas. SurvivalComms Makes more videos with this antenna analyzer format, but specifically for GMH and vhf uhf. As this antenna has 6 inches of resonator, then has a coil of 6 turns and size approximately 6 centimeter, then has another resonator of 8.5 inches. So this type of antenna is more suited to UHF GMRS? To further increase the bandwidth of this antenna in GMH UHF, should you increase more the resonance or reduce, or even increase the number of coil or reduce? Because our idea is UHF GMRS / FRS, but to increase the bandwidth across the 70 cm range. Now if you have three resonators, will the antenna have a higher gain in uhf GMRS / FRS SurvivalComms?

[@Ibelieve218]

what about dual band

[@survivalcomms]

This works so-so on UHF as well. The angle of radiation is not as good as it could be. Thanks for watching !

[@krisraps]

It's Receive Only, RIght? :) Good Project :)

[@survivalcomms]

It transmits just fine. Still working fine today.

[@jloaiza9188]

How much did you cut for uhf 6” or 5 3/4 ?

[@survivalcomms]

With the height of this base it was 5.75" When you look at the overall length of the whip and base over the NMO connector it was a tad over 6 inches. Thanks for watching !

[@jloaiza9188]

@@survivalcomms thanks for responding 👍

[@survivalcomms]

@@jloaiza9188 You are welcome - anytime we can bend e-waste to our will it's a bonus.

[@robsdeviceunknown]

I'm still learning HAM. This is definitely a nooby friendly channel. I didn't understand a damn thing you said lol

[@survivalcomms]

Keep your eyes peeled I'm going to do a video on antenna theory that might clear things up a bit. I will be happy to answer any specific questions on the subject matter as well. Thanks for watching !

[@attilarivera]

👏👏👏👏👏👏👏👏👏👏👏👏👏👏👏

[@survivalcomms]

Thanks for watching !

[@faditech6793]

By the way, here is a tip try "Rat Tail" or "Counterpoise" if you need to use a whip or ducky antenna, it increases reception by far - Full details at: kzbin.info/www/bejne/pIq5f6uBr9GXY8k

[@survivalcomms]

I have been doing that for years now. It is a great adjunct. I have it as part of my bugout bag radio video kzbin.info/www/bejne/o5PEeqWmerx8gsk Thank you and thanks for watching !

[@enriquedario2835]

I know I'm kind of randomly asking but does anyone know a good site to stream newly released movies online ?

[@elishashawn3188]

@Enrique Dario i watch on flixzone. Just search on google for it :)

[@tomasrussell6594]

@Elisha Shawn definitely, I have been using flixzone for years myself =)

[@enriquedario2835]

@Elisha Shawn Thanks, I went there and it seems like they got a lot of movies there =) Appreciate it !!

[@user-pc5hz5zu2e]

nnj

[@survivalcomms]

Thanks for watching !