Any ham radio guys here? AC8ZL

So, I use both end-fed half-wave and end-fed random wire antennas. For POTA activations and in my RV, I use a 40m EFHW which is about 66' long and is resonant on 40, 20, 15, and 10m, meaning that it can be used without a tuner on those bands. I'm actually doing a "build session" this weekend at our local hamfest, walking through folks through the process of building one. If you're interested, ARRL has a very nice EFHW kit that goes for about $70 and is what I use as my main antenna while RV'ing. There are lots of other kits out there, and I've built and used kits by KM4ACK, N5FY, and others. And since the antenna is little more than a toroid with a 7:1 ratio of windings (plus usually a 100 pF capacitor), building one from scratch is PDE (pretty darn easy).

At home, I use an end-fed random wire. As you probably know, a "random wire" is anything but "random." It has to be cut to a precise length so that it is not resonant on any frequencies of interest, nor any of those frequencies' harmonics. My home antenna is 71' long and is usable on 80 through 6 meters. But since it's not resonant on anything, it definitely needs a tuner. For me, since I live in an HOA neighborhood and the only antenna I can have is a wire thrown up in a tree, a random wire gives me the most flexibility for my situation.

For my POTA activations, I use lightweight versions of either antenna, but mostly the EFHW. In fact, I can keep my radio (a KX2), my paddle, the antenna, a throw weight, coax, and a bunch of other stuff, in a little pack smaller than a lunch box.

I'm not really aware of any disadvantages to either antenna, although the random wire probably isn't as efficient as other wire antennas. But, as they say, everything's a tradeoff and the band flexibility more than makes up for it.

Hope that helps,
73 Skip K4EAK
 
So, I use both end-fed half-wave and end-fed random wire antennas. For POTA activations and in my RV, I use a 40m EFHW which is about 66' long and is resonant on 40, 20, 15, and 10m, meaning that it can be used without a tuner on those bands. I'm actually doing a "build session" this weekend at our local hamfest, walking through folks through the process of building one. If you're interested, ARRL has a very nice EFHW kit that goes for about $70 and is what I use as my main antenna while RV'ing. There are lots of other kits out there, and I've built and used kits by KM4ACK, N5FY, and others. And since the antenna is little more than a toroid with a 7:1 ratio of windings (plus usually a 100 pF capacitor), building one from scratch is PDE (pretty darn easy).

At home, I use an end-fed random wire. As you probably know, a "random wire" is anything but "random." It has to be cut to a precise length so that it is not resonant on any frequencies of interest, nor any of those frequencies' harmonics. My home antenna is 71' long and is usable on 80 through 6 meters. But since it's not resonant on anything, it definitely needs a tuner. For me, since I live in an HOA neighborhood and the only antenna I can have is a wire thrown up in a tree, a random wire gives me the most flexibility for my situation.

For my POTA activations, I use lightweight versions of either antenna, but mostly the EFHW. In fact, I can keep my radio (a KX2), my paddle, the antenna, a throw weight, coax, and a bunch of other stuff, in a little pack smaller than a lunch box.

I'm not really aware of any disadvantages to either antenna, although the random wire probably isn't as efficient as other wire antennas. But, as they say, everything's a tradeoff and the band flexibility more than makes up for it.

Hope that helps,
73 Skip K4EAK

Great info and lines up with what I've read about these wire antennas. With the EFHW, even if the SWR was a little high on parts of a band, it seems like XCVR's like the IC-7300 have a built in tuner that would solve the issue. I'll take a look at the ARRL kit. From some of the videos I've seen it certainly doesn't look like it would be hard to make a matching transformer. I'd sure like to attend your "build session".

One commercially built kit that looks impressive is the Chameleon EMCOMM II. It appears to be a 60' end fed long wire.

With either the EFHW or the long wire, do you have any issues with getting RF back into your operating area? Seems like some folks are having to use some type of RF suppression/chock in the coax feedline.
 
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With either the EFHW or the long wire, do you have any issues with getting RF back into your operating area? Seems like some folks are having to use some type of RF suppression/chock in the coax feedline.

Yes, RF coming back is an issue sometimes. At my home QTH, I do use a simple choke where the coax enters the house. I've never used anything on the EFHW antennas, although you're right ... many people stick a choke or some ferrite beads at the transceiver end of the feed line. Obviously, in both cases, the coax shield is operating as the other half of the antenna, so one does not choke it at the wire (which would defeat the purpose).

Which reminds me, I forgot to mention that some EFHW and random wire antennas will use a counterpoise. I have a 15' counterpoise on my ARRL EFHW antenna, and the random wire antenna at my home has an option for a counterpoise. In that latter case, I've tried it both ways and it actually seems to work better without the counterpoise. YMMV.

73 Skip K4EAK
 
So, I use both end-fed half-wave and end-fed random wire antennas. For POTA activations and in my RV, I use a 40m EFHW which is about 66' long and is resonant on 40, 20, 15, and 10m
73 Skip K4EAK

I've now read quite a bit about both antennas and I feel in my case the EFHW using a 49:1 transformer would meet my needs. I'm really just interested in 40 and 20m so resonance and low SWR is not that important on other bands.

It sounds like you are not using a tuner on your EFHW so what kind of SWR readings are you getting on the bands you mention? I also found my neighbor has an MFJ antenna analyzer so I feel I can reach a pretty good compromise by some tuning.

The ARRL kit is interesting but I have wire, parts, etc and just need the transformer so I'm looking at several commercial ones and particularly the ones made by Balun Designs. I really should build the tansformer from scratch but unless you have some of the parts, it doesn't seem like the cost is that much more. Looking at articles and Youtube videos I have not found any that are resonant enough on 40-10m.
 
I've now read quite a bit about both antennas and I feel in my case the EFHW using a 49:1 transformer would meet my needs. I'm really just interested in 40 and 20m so resonance and low SWR is not that important on other bands.

It sounds like you are not using a tuner on your EFHW so what kind of SWR readings are you getting on the bands you mention? I also found my neighbor has an MFJ antenna analyzer so I feel I can reach a pretty good compromise by some tuning.

The ARRL kit is interesting but I have wire, parts, etc and just need the transformer so I'm looking at several commercial ones and particularly the ones made by Balun Designs. I really should build the tansformer from scratch but unless you have some of the parts, it doesn't seem like the cost is that much more. Looking at articles and Youtube videos I have not found any that are resonant enough on 40-10m.

I have a couple QRP radios; one (a Venus SW-3:cool: doesn't have a tuner; the other (a KX2) does, but I usually put the tuner in bypass mode when using the EFHW antennas. Here are the SWRs for the antenna I use most often:
40m: SWR < 1.5 across the entire band, with 1.24 and 1.14 at the CW portion edges.
20m: SWR < 1.2 across the entire band, with 1.2 and 1.07 at the CW portion edges.
15m: SWR < 1.52 across the entire band, with 1.52 and 1.31 at the CW portion edges.
10m: SWR < 2.0 across the entire band, with 1.87 and 1.63 at the CW portion edges.
I also added a link for 30m, and it is < 1.2 across the entire band with the link pulled.

My QRO radio is an IC-7300 and I sometimes will hit the TUNE button just for the fun of it, although I doubt it's ever necessary.

It is true that some EFHWs seem to work better at one end of their resonant range than at the other. At the antenna build workshop I did this past weekend, all 10 antennas were well below 2:1 on 40-20-15m, and all were slightly above 2.0 at the outer edges of 10m. I'm not sure why that is. It's on my list of things I want to learn about, but it's a REALLY long list. ;)

You're probably right about buying something off the shelf than trying to cobble together the parts. I've never used a Balun Designs unun, but I've heard good things about the company. I'm sure it'll work well for you.

Let me know how things work out for you. This is interesting ...
73 Skip K4EAK
 
I'm getting ready to leave on a 3-week trip to Florida, which will include Hamcation, Fort Wilderness, Kennedy Space Center, and a bunch of POTA activations. Most of the time my radio setup will be out on a park bench, but if I want to operate at the dinette table I just realized I don't know how I'm going to bring the coax into the RV. I'm not opposed to a permanent bulkhead connector pass-thru, but I don't know where that would go.

How do you guys bring the coax in?

Thanks very much,
73 Skip K4EAK
 
I'm getting ready to leave on a 3-week trip to Florida, which will include Hamcation, Fort Wilderness, Kennedy Space Center, and a bunch of POTA activations. Most of the time my radio setup will be out on a park bench, but if I want to operate at the dinette table I just realized I don't know how I'm going to bring the coax into the RV. I'm not opposed to a permanent bulkhead connector pass-thru, but I don't know where that would go.

How do you guys bring the coax in?

Thanks very much,
73 Skip K4EAK

Hi Skip!

We're doing something similar ourselves. I've run coax through a window or even through the rubber seal at the corner of a slide down by the floor (just bend the seal back a little and you'll see a pretty decent gap). I haven't done POTA yet, but since I like staying in parks more than private campgrounds it makes sense to activate a few. I'll be taking along a Yaesu FT-891 and a couple antenna options but I might just operate out of my truck a little since I have HF in there.

Are you camping at the Hamcation location? We could start a Hamcation Grand RV rally!

-Mike, K8AN
 
Hi Skip!

We're doing something similar ourselves. I've run coax through a window or even through the rubber seal at the corner of a slide down by the floor (just bend the seal back a little and you'll see a pretty decent gap). I haven't done POTA yet, but since I like staying in parks more than private campgrounds it makes sense to activate a few. I'll be taking along a Yaesu FT-891 and a couple antenna options but I might just operate out of my truck a little since I have HF in there.

Are you camping at the Hamcation location? We could start a Hamcation Grand RV rally!

-Mike, K8AN

Thanks ... I'll check the slideout location.

Yes, I'm camping on the grounds at Hamcation. My RV club (FMCA) has its own amateur radio chapter. We all camp together in the same area. I missed last year, but the year before that we had 23 (!) RVs all parked together. It's great fun. Most of the RVs are motor homes, but I like your idea ... we could enlist a bunch of GD owners and stage a take-over! :)

I also have an FT-891 in my truck, running to an ATAS-120 mounted at the front of the bed. It works pretty well when I'm doing a quick activation and it's cold, raining, or otherwise more than my aging body wants to deal with.

Thanks again,
73 Skip K4EAK

[On edit] P.S. I see from your qrz page that you're down in Ft. Lauderdale. It's a haul, but if you'll be up at Hamcation, let me know and you can swing by our RV gathering and we can compare notes on radio setups in RVs.
 
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Thanks ... I'll check the slideout location.

Yes, I'm camping on the grounds at Hamcation. My RV club (FMCA) has its own amateur radio chapter. We all camp together in the same area. I missed last year, but the year before that we had 23 (!) RVs all parked together. It's great fun. Most of the RVs are motor homes, but I like your idea ... we could enlist a bunch of GD owners and stage a take-over! :)

I also have an FT-891 in my truck, running to an ATAS-120 mounted at the front of the bed. It works pretty well when I'm doing a quick activation and it's cold, raining, or otherwise more than my aging body wants to deal with.

Thanks again,
73 Skip K4EAK

[On edit] P.S. I see from your qrz page that you're down in Ft. Lauderdale. It's a haul, but if you'll be up at Hamcation, let me know and you can swing by our RV gathering and we can compare notes on radio setups in RVs.

Well, we're not in Ft. Lauderdale yet. Leaving Ohio in a couple days when the weather clears a bit. We'll get to the Hamcation on Wednesday and have to leave Saturday to get set up for a SuperBowl party in FTL. You had me checking my QRZ page, though -- I thought I was way out of date! I do need to update the equipment, though. I'm running an FTM-400 and FT-891 in my F350 now. The 891 runs into an ATAS-120 just like you do. I used to run a tarheel 200A-HP but I haven't figured the mount on this truck yet. It's a great antenna but it's also always in the way when it comes to drive-thru, parking garages, car washes, etc.! I may set it up with an A-B switch so I can mount the big antenna and dismount it at will.

On our way south we'll be spending a week at Skidaway Island S.P., just south of Savanah. That's probably my first good opportunity to activate a POTA. It will be my first, so it will probably be pretty haphazard! LOL! Picture an episode of "I Love Lucy"!

I'll look you up at Hamcation. My brother, KO4HG, was supposed to make it but something came up at the last moment. We may meet up with him somewhere in FL later on. TBD.

So, one more call out to any forum members who may be hams and may be attending the Hamcation this February in Orlando. Anybody else?

73,
Mike
K8AN
 
Well, we're not in Ft. Lauderdale yet.

(snip, snip)

I'll look you up at Hamcation. My brother, KO4HG, was supposed to make it but something came up at the last moment. We may meet up with him somewhere in FL later on. TBD.

So, one more call out to any forum members who may be hams and may be attending the Hamcation this February in Orlando. Anybody else?

73,
Mike
K8AN

Great idea to put out a call for other hams going to Hamcation, so I started a separate thread (since I'm not sure who's following this one). We'll see who'll be there.

73 Skip K4EAK
 
Hello, K4EJD here and my wife and I are waiting for our house to sell so we can get our truck and trailer. I'm planning on having a ham shack in the garage area so any input would be welcome! im thinking going with ICOM 7300. No clue what antenna to go with though.
LLAP
 
Hi Skip!

We're doing something similar ourselves. I've run coax through a window or even through the rubber seal at the corner of a slide down by the floor (just bend the seal back a little and you'll see a pretty decent gap). I haven't done POTA yet, but since I like staying in parks more than private campgrounds it makes sense to activate a few. I'll be taking along a Yaesu FT-891 and a couple antenna options but I might just operate out of my truck a little since I have HF in there.

Are you camping at the Hamcation location? We could start a Hamcation Grand RV rally!

-Mike, K8AN

Back to how to run the coax into the RV, I came up with a solution. Our XLS 23LDE has a port with an RG6 F-connector. We don't use a TV outside, so I replaced that with an 4" SO-239 bulkhead connector, and then ran a short length of RG-8X to another bulkhead connector on the face of the dinette seat.
IMG_0777.jpgIMG_0778.jpg

73 Skip K4EAK
 
WX4CCC here, planning on doing 3 radios in my rig, HF/VHF/UHF and a Lime full Xmint 4 port SDR. Also looking for antenna advice, especially for HF.
 
WX4CCC here, planning on doing 3 radios in my rig, HF/VHF/UHF and a Lime full Xmint 4 port SDR. Also looking for antenna advice, especially for HF.

I don't know what your requirements for an antenna are, but I've recently put up an end fed half wave antenna and I feel I'm getting good results considering it's not up very high.

SWR readings are very acceptable on 40, 20, and 15m. I bought a few parts and made a 49:1 matching transformer, and then strung up about 67 ft of #14 stranded wire. Lots of info on YouTube and building this type of wire antenna.
 
Right now I have a pair of hamsticks for 15m and 20m. The attachment point is on a painter's pole, and I sit outside. Today I thought I'd try using the surplus 12V 105AH LiFePO4 batteries that I don't need with my new setup. One was under 4 volts and the other was just under 10. I've got that one on a charger now. I suspected that there was a problem with one of those batteries, but no one would believe me. The batteries have been disconnected for about a month now.

Eventually I'll run a pair of wires to where I can plug in a radio and then I'll be set.
 
WX4CCC here, planning on doing 3 radios in my rig, HF/VHF/UHF and a Lime full Xmint 4 port SDR. Also looking for antenna advice, especially for HF.

Since I like camping in new places and I really don't know the setup of a new site, I was thinking about going this way for an HF antenna on the RV. https://mfjenterprises.com/products/mfj-2104

I should be able to set this up wherever I go.

I haven't used that MFJ "octopus" model, but I've used hamstick dipoles a lot and they work fine. Since the elements are base-loaded, they don't work as well, obviously, as a longer wire, but for temporary setups they'll do. I also have the dipole connector mounted on the top of a 12' extendable painter pole that I attach to the rear ladder via a Flag Pole Buddy.

However, when circumstances permit, I also prefer to go with an EFHW thrown up in a tree. It's resonant on the four bands I use most often (40, 20, 15, and 10) and is easy to deploy using an arborist weight/line, and very efficient. As noted above, there are gazillions of pre-made, kits, and DIY versions. They're all basically the same and work great. I've found that sometimes an EFHW will work better with a counterpoise, but the ordinary method of using the coax shield as the counterpoise works well enough in most cases. If trees aren't an option, for one reason or another, I sometimes use a collapsible pole in a Flag Pole Buddy as the attachment for the EFHW wire end, although the logistics of that setup can get cumbersome.

Where an EFHW won't work (because no trees or park restrictions on putting wires in trees), my next-best option is usually a Wolf River Coil, except that I use it with an MFJ-1979 (17') collapsible whip. That gives me all bands 40m and higher and works great.

And finally, you didn't ask, but I also have an FT-891 installed in the truck and an ATAS-120 mounted on the front of the bed. The 891 is a so-so radio, and the ATAS-120 is a so-so antenna, but who cares? If I'm just driving around and want to get on HF, or do a quick park activation, the combination works well enough. In fact, operating this way, sitting in the truck, is my go-to way to operate when all else just won't work.

Hope that helps,
73 Skip K4EAK
 
I don't know what your requirements for an antenna are, but I've recently put up an end fed half wave antenna and I feel I'm getting good results considering it's not up very high.

SWR readings are very acceptable on 40, 20, and 15m. I bought a few parts and made a 49:1 matching transformer, and then strung up about 67 ft of #14 stranded wire. Lots of info on YouTube and building this type of wire antenna.


Here is what I am looking at for HF, have built several of them and they seem pretty solid. Setup would be fairly quick once you get the ground planes installed and the pole up. Not optimal but a good quick RV solution. https://mfjenterprises.com/products...37251&pr_ref_pid=4381042573411&pr_seq=uniform . Process: I tune the antenna then number and mark the flyout radials and horizontal planes for quick assembly and setup using the same cable and tuner setup. I think this would be fairly quick setup and good solid DX'ing. Thought?
 
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When traveling to my campsite, I use a ICOM 5100. I will be staying at camp off and on this year, and am looking at bringing my ICOM 7300 with me. Still looking for an antenna. Thinking about a Chelegance MC 750. Anyone have any experience with that particular antenna? - KD4TW
 
When traveling to my campsite, I use a ICOM 5100. I will be staying at camp off and on this year, and am looking at bringing my ICOM 7300 with me. Still looking for an antenna. Thinking about a Chelegance MC 750. Anyone have any experience with that particular antenna? - KD4TW

I bring my 7300 with me on most trips, although I usually use my KX2 most of the time.

IMG_0864.jpg

I haven't used the Chelegance antenna, but a Parks on the Air guy I follow (Thomas K4SWL) uses it a lot and loves it. If you go to his website (http://qrper.com) and search for it, you'll find lots of field reports and videos on that antenna. FWIW, I often use a Wolf River Coil, which is a similar concept (base-loaded vertical with several radials) and it's fine. Assuming the Chelegance is that good or better, I'm sure you'd like it.

73 Skip K4EAK
 

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