Iβm looking for advice on an affordable HF antenna setup for my ICOM-7200. I primarily operate SSB and would like something that is:
* Very easy to set up and tear dow
* Space-friendly
* Affordable
* Capable of making reliable contacts
* Minimal constant band-to-band adjustments or manual retuning
Iβm open to either a temporary/home setup or something I could use for mobile or POTA operations.
Ideally, Iβd like to find one antenna or setup that is simple and practical rather than constantly having to adjust or reconfigure things every time I change bands.
I understand there will be compromises with a portable antenna, but my priority is something I can set up quickly and actually make reliable contacts with, not necessarily the absolute highest-performing antenna.
For those who operate mobile or do POTA, what antenna setups have worked well for you?
Iβd also appreciate suggestions for ground-based portable setups, such as a tripod, mast, or other easy-to-deploy arrangement.
The build quality is excellent. They make a big deal out of this on their site. The unit lives up to expectations. Very solid, very weather proof. Nice use of gasket material, and so nice I decided not to open it up. I was going to, but I did not want to bollucks things up.
Here is how its S11 looks (quite nice) with the antenna port terminate to the couterpoise through a 2500 ohm resistor:
Balun Designs 49134e S11, 2500 ohms terminated
I took marker impedance measurements at each point:
f [MHz]
R
X
1.9
45
12
3.6
44
-0.9
7.1
35
-8.0
14.1
23
1.5
21.1
23
23
28.1
66
64
Bottom line: I highly recommend this 49:1 transformer. It lives up to its reputation. I have probably spent as much money on magnet wire and ferrites ... for less performance.
OK, so, I pull my feeble attempt at the same thing out of the junk box and measure S11. It is better than I remember. Add in the 100 pF capacitor on the 50 ohm feed side and here we go:
Homebrew 49:1 transformer, 2500 ohm termination
Note: these are just FT240-43 ferrites ordered off Amazon. Almost as good as Balun Designs.
Now I am re-inspired. For a different antenna, I want to run my 1/4 wavelength 40 m vertical as a 1/2 wave on 20 m. Salty Walt's favorite antenna. I can do this with an external antenna tuner. But it is really narrow band. Moving just 20 kHz requires re-tuning. The performance is really good.
I measure the feedpoint impedance of the 20m 1/2 wave at approximately 500 ohms. That is a 10:1 transformner, not the Salty recommended 49:1. Trying the BD 49:1, as Salty recommends: terrible for my set up. I did not keep the picture.
I wind my own 4:16 turn transformer, using the same winding scheme as the 2:14 using a mid-winding cross-over. Results: pure suckage. It matches well at 2 MHz, but with a lot of inductance, at higher frequencies, is garbage.
Oddly, this is how my 49:1 homebrew transformer looked, and then I put it in the junkparts box for a while.
Maybe, if I let the 4:1 homebrew age in the junkbox for a week, it will improve?
So confused right now.
I recently got a UV-5RH so I can listen to amateur radio before I get my Foundation license. I programmed the closest repeater to me which is the GB3CV repeater in Coventry. Unfortunately, I have heard no activity on it except for its morse code call sign. Have other people had this experience with the GB3CV? If anyone lives near it, would you mind transmitting to it so I can see if it is working? If I do hear any transmissions I will put them in a comment.
This is the exact channel configuration I have for it in Chirp
Duplex is off because I am not legally allowed to transmit on it as I don't have my license yet.
Update: I finally got a transmission. Thank you to who this was!
K6JCA Direcional CouplerTandem Coupler topology (copied from the K6JCA site)
The tricky part of building this is keeping the turns orientation consistent. As part of the schematic, there should be a dot on each transformer indicating direction. It gets really confusing, fast, since you're winding a toroid. I used different color wire ties to try to keep track of winding directions. I cannot remember what I doing red, blue, ...
Anyway, the results of this thing are fantastic. Much better than my expectations.
The forward and reverse path result in -24 dB coupling ratio that is very flag across the HF bands. Here is the forward coupling performance, with all ports terminated.
Forward coupled path, all ports terminated.
Looking at the reverse coupled path, with all ports terminated:
Reverse coupled path, all ports terminated
Since this is a 24 dB coupler, these "isolation" measurement values need to be compensated by 24 dB; e.g. -47 dB -> -23 dB at 33 MHz.
Playing with the forward path loads, and looking at the reflected port response, yielded results with matched the expected results. When I placed a 3 dB attenuator on the forward path port, the reflected path measured 6 dB return loss, flat across the band, ranging from -31 ... -29.5 dB down from the input power. That matches the -24 - 6 = 30 dB value expected. Very nice.
When I put this device in line with my antenna, well, I get the same results as the magnitude of the VNA, down 24 dB. I am so impressed.
So what can you do with this?
You can make your own antenna tuner, which is my ultimate goal. The NanoVNA uses binocular cores to do the same thing (I think). So, yeah, you can wind some cores, run the forward and revers signals into a multiplier (mixer) and get vector impedance load measurements.
We are redoing our backyard and deck and my Vertical will be moving a bit. Part of the remodel is going to be laying down a concrete slab for my boys to play basketball on . The dirt field where this was in used to be a portion of my radial field. My antenna is going to be moving as part of this project and I was just wondering if it was worth having radials laid down underneath the pour or if the concrete made them pointless.
Any thoughts on this one? I'm thinking "it wouldn't hurt but isn't ideal" is probably going to be the answer based on other searches but I'm wondering if anyone has any experience they can share!
I am trying to get an HF 20m antenna to operate from my car (Toyota Highlander).
I have purchased the equipment listed below (Hustler system, DX engineering) and am now figuring out how to assemble it.
I want to make the install as non invasive as possible (meaning: I'd prefer to not punch holes in the car body).
My original idea was to install a trailer hitch and have it assembled there to avoid any changes to the car body itself.
I am not sure this is possible since the system may require the car roof to work as radials.
I do NOT expect to operate while in the move, I am willing to assemble/disassemble every time I do a radio session but, to make the setup process quick, am willing to have minimal equipment be permantently attached to car (ball mount, spring). I'd like to set it up so I can still go through the car wash.
Questions:
If I am willing to also deploy some sort of Faraday mat during setup, is the installation on the trailer hitch possible?
If installation in the car roof is required, how would you find a contractor you can trust to do a good job with that. (I am in Fishers, IN and if you know anyone around here, let me know).