Radioditty HF-009 any good?

[TNFrank]

Are these antennas any good for general HF use?

[WRYS709]

Here I am pre-choke:

[WRYZ926]

For those that have the HF-009 or are thinking of getting one.

The ground radials use 3mm banana plugs. You can get some BNTECHGO 18 Gauge Silicone Wire and some 3MM Banana Plug Bullet Male Female Connector and make your own ground radials.

You can fit at least 2 or 3 wires per 3mm male plug.You can also make Y or W adapters so that you can use more radials at one time.

S0 it is possible to greatly increase the number of ground radials with the HF-009. You could easily increase to 27 ground radials by using 3 W adapters and 3 ground radials per 3mm male plug. Another bonus is that you can make the radials different lengths too. 

I suggested 18 gauge wire since that is a good size. But you can always go to 20 or 22 gauge wire to fit more into each 3mm banana plug.

The REZ antenna comes with four 33 ft radials and I went to 24 8.6ft radials and it made a noticeable improvement. I basically cut the new radials to be close to a 1/8th wave. 

Radial lengths are not critical for ground radials. Now you do need to cut and tune elevated radials for each band.

The REZ base has eight 4mm holes. I put 3 18 gauge wires per 4mm banana plug and also made eight Y adapters. So I can run up to 32 ground radials.

[WRYS709]

How do you measure your wire for exact length radials before cutting it?

My MFJ 1880-T 80 meter whip requires 51 feet 6 inches. 

[WRYZ926]

5 minutes ago, WRYS709 said:

How do you measure your wire for exact length radials before cutting it?

My MFJ 1880-T 80 meter whip requires 51 feet 6 inches. 

Length doesn't matter for ground radials. 

You cut elevated radials for a 1/4 wave. It's no different than tuning the vertical wire/telescoping whip.

[SteveShannon]

10 minutes ago, WRYS709 said:

How do you measure your wire for exact length radials before cutting it?

My MFJ 1880-T 80 meter whip requires 51 feet 6 inches. 

A tape measure. 

[WRYS709]

10 hours ago, WRYS709 said:

How do you measure your wire for exact length radials before cutting it?

My MFJ 1880-T 80 meter whip requires 51 feet 6 inches. 

 

10 hours ago, WRYZ926 said:

Length doesn't matter for ground radials. 

You cut elevated radials for a 1/4 wave. It's no different than tuning the vertical wire/telescoping whip.

[WRYZ926]

@WRYS709 your photo shows what the length of the ground plane wire should be for MFJ telescoping antennas. And from the looks of it they are only calling for one ground plane wire. Most other 1/4 wave telescoping whip antennas use at least 4 ground radials, the exception being the HF-009 with only 3 ground radials.

Calum-DX Commander is an excellent source for information on ground mounted 1/4 wave antennas. A ground mounted 1/4 wave antenna will benefit from more radials until you get to the point of diminishing returns. And that is a high number of ground radials.

The length of ground radials for a ground mounted 1/4 wave antenna is not super critical. My own testing shows that 24 8.6 ft radials works better on the 20m band than 4 33 ft radials do.

Once you elevate a 1/4 wave antenna then you definitely need to cut and tune any radials for each band. Most people will run elevated 1/4 wave antennas and radials at least 6 feet above the ground on a tripod.

This is no different than most base station antennas that use 3-4 radials. Base station antenna radials are cut and tuned for the lowest band that the antenna is resonant on.

Elevated 1/4 wave antennas such as the POTA Performer only use two elevated radials. This tends to make the antenna more directional. 

Using a single or two radials will make the antenna directional. Having the radials elevated or on the ground doesn't make a difference.

There are different ways to setup a 1/4 wave antenna. More radials definitely helps when ground mounted.

[WRYZ926]

@WRYS709 Thank you for letting us know how that capacitance hat worked.

 

And if MFJ is calling for a certain length for their antennas then go with what they say as a starting point. Part of the fun is experimenting to see what works better.

[WRYS709]

On 2/9/2026 at 4:59 AM, WRYZ926 said:

And if MFJ is calling for a certain length for their antennas then go with what they say as a starting point. Part of the fun is experimenting to see what works better.

I used my 25' tape measure to mark off 25 feet and then 9 inches on my front fence.

I then double looped it with my 26 gauge BNTECHGO spool to give me the 51 feet 6 inches needed and then a little more for error.

I banana jacked it (4mm) and plugged it into a Desco 09780 Ring Terminal that I installed on a Mueller Electric Heavy Duty Steel Clip and clipped it on the Etsy Choke that I installed on my Tripod Mount and operated tonight on 80 meters with the MFJ 1880-T whip.

Not any success SSB or FT8, but I could see on one of the WebSDRs that 80 was collapsing.

So I swapped it for the 40 meter Thai-Whip and kept the 51/6 counterpoise on it and started operating 40 meters.  Had a successful QSO over to W7ASU Arizona State University's college station operating on an ARRL School Club Roundup tonight!

Then got an FT8 to Wisconsin and then the sky opened up!!!

I got pretty wet collapsing the whip and tripod and disconnecting and getting the coax inside.  I left the 51/6 counterpoise outside; maybe it will shrink the extra inch or two I cut it for! hahaha

Next project to cut some 5 meter and 10 meter lengths from the BNTECHGO spool and putting banana jacks on them; maybe putting 3 counterpoise to one banana jack and add more Desco's to my antenna mount, so that the Mueller Clip becomes my go to for POTA.

By the way, the smaller banana jacks from my Radioddity HF-009, easily slip into the 4mm banana jacks I purchased so as to be able to use them as well on the HF-009 and my tripod as needed.

[WRYZ926]

It's nice having options. Nice to hear that the 3mm banana jacks do fit into the 4mm jacks.

Longer ground radials won't hurt for higher bands. REZ Antennas includes 33 foot ground radials with all of their antenna kits which is a 1/4 wave on 80m. That works fine for the higher bands. Going shorter won't hurt either as long as you have more ground radials. 24 8.6 Ft radials works better than the four 33 ft radials on 20m and higher with my REZ antenna.

Again, the radio length is only critical if you are using elevated radials.

 

[WRYS709]

2 hours ago, WRYZ926 said:

It's nice having options. Nice to hear that the 3mm banana jacks do fit into the 4mm jacks.

Longer ground radials won't hurt for higher bands. REZ Antennas includes 33 foot ground radials with all of their antenna kits which is a 1/4 wave on 80m. That works fine for the higher bands. Going shorter won't hurt either as long as you have more ground radials. 24 8.6 Ft radials works better than the 4 33 ft radials on 20m and higher with my REZ antenna.

Again, the radio length is only critical if you are using elevated radials.

 

Note: the 3mm banana plugs fit into my 4mm banana PLUGS, as if they were a wire I then screw down to tighten down. 

The choke I purchased was pricey, but it works!

[WRYZ926]

Just now, WRYS709 said:

Note: the 3mm banana plugs fit into my 4mm banana PLUGS, as if they were a wire I then screw down to tighten down. 

The choke I purchased was pricey, but it works!

That still gives you options.

And yes common mode chokes do work and keep RF out of your radio.

[WRYS709]

2 minutes ago, WRYZ926 said:

That still gives you options.

And yes common mode chokes do work and keep RF out of your radio.

How did you decide on 8.6 and 4.33 (ft?)?

[WRYZ926]

5 minutes ago, WRYS709 said:

How did you decide on 8.6 and 4.33 (ft?)?

I meant four radials that are 33ft long. And how I came up with 8.6 feet is that is approximately a 1/8 wave on 20 meters.

[WRYS709]

45 minutes ago, WRYZ926 said:

I meant four radials that are 33ft long. And how I came up with 8.6 feet is that is approximately a 1/8 wave on 20 meters.

Radioddity includes 3 - 5 meter radials with their HF-009, so how did they compute that length?

[WRYZ926]

30 minutes ago, WRYS709 said:

Radioddity includes 3 - 5 meter radials with their HF-009, so how did they compute that length?

The HF-009 is using 1/4 wave ground radials for 20m. A 1/4 wave at 14.250 is 16.98 feet or 5.17 meters. The length of ground radials is not critical so it is fine to round up or down to the nearest foot or meter, which is what Radioddity did.

Here is a good wavelength calculator: ahsystems.com frequency wavelength calculator.

That is how I came up with 8.6 feet for my 24 short ground radials as that length is a 1/8 wave for 20m.

You should double the number of ground radials if you use 1/8 wavelength compared to 1/4 wavelength ground radials for good performance.

[WRYS709]

I recovered the 51’ 6” counterpoise I left out in the rainstorm and until the Winders I purchased on Etsy arrive, I wound it around a cardboard toilet paper tube! 

Even with silicone wire, I don’t want to have to untangle it again!

i am building up the nerve to try out my HF-009 on the tripod! 

[WRYZ926]

17 minutes ago, WRYS709 said:

I recovered the 51’ 6” counterpoise I left out in the rainstorm and until the Winders I purchased on Etsy arrive, I wound it around a cardboard toilet paper tube! 

Even with silicone wire, I don’t want to have to untangle it again!

i am building up the nerve to try out my HF-009 on the tripod! 

What ever works to keep the radials neat.

Remember that if you elevate the HF-009 on a tripod and also use elevated radials that you will need to tune the radials for each band.

[WRYS709]

4 minutes ago, WRYZ926 said:

What ever works to keep the radials neat.

Remember that if you elevate the HF-009 on a tripod and also use elevated radials that you will need to tune the radials for each band.

Im lazy and plan to have the untuned radials just follow the surface after they hit the ground. Proper procedure?

[WRYZ926]

7 minutes ago, WRYS709 said:

Im lazy and plan to have the untuned radials just follow the surface after they hit the ground. Proper procedure?

That should be fine. The only real way to know for sure is to try it.