Tag Archives: CHA TDL

Testing the new Chameleon Tactical Delta Loop (CHA TDL) antenna

Chameleon Antenna has sent me a number of their antenna systems to evaluate in the field over the past few months at no cost to me. I appreciate not only the opportunity to test these antennas, but to provide the company with my frank feedback.

As I’ve mentioned previously, Chameleon antennas are military grade and build here in the US (check out Josh’s tour of their factory).  You pay a premium price–compared to imported options–but their gear is built for performance, easy deployment, and longevity.

What has impressed me most about Chameleon gear is how flexible and modular it is. Their antenna systems are adaptable to almost any situation and always built around the idea of emergency communications.

Recently, Chameleon sent me their new CHA TDL or Tactical Delta Loop antenna. This vertical loop antenna has been designed to be portable, and tunable from 3.5 to 54.0 MHz (80-6M), but, as Chameleon points out,  “is most effective on the bands from 10.1 to 54.0 MHz (30-6M). ”

TDL deployment

If I’m being perfectly honest, I wasn’t sure what to expect this antenna to look like–in terms of size–once deployed, so I set it up in the front yard prior to taking it to the field.

Set up couldn’t have been more simple: attach the 17′ telescoping whips to the stainless steel spike (with one whip attached to the Hybrid Micro), extend the whip sections, then attach the loop wire to connect the tips of both whips.

It might have taken me four minutes to set up the TDL on the first go.

This antenna needs a little space  for sure: this isn’t one you could easily deploy in a dense forest, but it has a very flat profile vertically. I can’t think of a single park I’ve activated that couldn’t accommodate the CHA TDL.

I like to try to give gear a fair chance when I do evaluations and thought I’d wait until propagation was at least stable before taking the TDL to the field and making a real-time, real-life video (as I used it for the first time). But, frankly, I’m way to impatient to wait for the sun to play fair! Trial by fire…

Lake Norman State Park (K-2740)

On Monday (March 15, 2021) I packed up the CHA TDL and headed to Lake Norman; one of my favorite parks to play radio.


Propagation left much to be desired that afternoon, but the weather was perfect.

I decided to pair the CHA TDL with my Icom IC-705. Since the CHA TDL requires an ATU, I connected the mAT-705 Plus.

NVIS on the low bands

I had no idea what to expect from the CHA TDL in terms of performance, but Chameleon notes that it provides Near-Vertical Incidence Skywave (NVIS) propagation on 40 and 80 meters. NVIS antennas are very popular for the military and for emergency communications since the propagation footprint is much closer to home than it might normally be.

NVIS is also a brilliant option for park and summit activators, especially if they’re activating in an area with a high density of park/summit chasers. For example, if you live and activate sites in the state of Maryland, employing a NVIS antenna might make your site more accessible to the DC metro area, Pennsylvania, Virginia, New York, Delaware, and New Jersey–regions that might otherwise be in the skip zone of your 40 meter signal.

On the air

Operating five watts CW, I started calling CQ POTA on 20 meters and snagged four stations in about seven minutes.

I was very pleased to work a station in California and one in Montana with five watts. (Though I need to check, this might have been my first MT station logged from a park.)

Next, I moved to 40 meters and was very curious if the TDL would provide me with proper NVIS propagation.

It did! One litmus test for me is when I work stations in Tennessee on 40 meters. Typically, I only log TN stations when on 80 meters or when I’ve configured one of my wire antennas for NVIS coverage.

Here are my logs from this 28 minute activation:

Here’s a QSOmap of the activation–the delineation between my four 20 meter contacts and eight 40 meter contacts is pretty evident:


Here’s my real-time, real-life video of the entire activation which also shows how the CHA TDL easily fit in among trees:

In a future video, I’ll show how I deploy the CHA TDL.

Unfortunately, I left my tripod at home, so apologies for the viewing angle as I operated the IC-705.


This first test of the CHA TDL really couldn’t have gone better.

I was able to easily deploy it on sloping ground, among trees, in a state park, and snag both locals and QRP DX within a brief window of time on the air.  All this, while our local star tried its best to interfere.

In terms of construction, the TDL is what I would expect from Chameleon: military grade.

For park activators and Emcomm purposes, the CHA TDL makes for a convenient, portable NVIS antenna on 40 and 80 meters.

While I have lighter, smaller footprint antenna options for SOTA, I must admit I’m very curious how it might perform on 20 and 17 meters from the summit of a mountain. The idea of being able to rotate the antenna and change the propagation footprint is very appealing. I’ll save this experiment for a summit that doesn’t require hours of hiking, though, and one where I know I can jab the stainless steel spike in the ground (i.e. not on top of a rocky mountain).

Any negatives? When I first deployed the TDL at home, we were having 30+ MPH wind gusts. When the gusts shifted, it did move the antenna. This could be remedied pretty easily by using a bit of fishing line filament to tie off one side of the loop. With that said, I’m not sure I’d configure the TDL as a loop if I expected strong winds. Also, as I mentioned earlier, this might not be the best antenna to pack if you plan to include a multi-hour hike in your activation.

And herein lies the brilliant thing about Chameleon Antennas: If I packed in the CHA TDL and found that winds were strong on site, I would simply configure it as a vertical instead of a loop!

The CHA MPAS Lite vertical

The CHA TDL can easily be configured as a CHA MPAS Lite portable vertical: all it’s missing is a counterpoise wire which you can buy separately from Chameleon or, better yet,  just use some spare wire you have on hand!

Or, you could configure it as a random wire antenna by directly connecting a length of wire to the Hybrid Micro transformer.

That’s the thing about Chameleon HF Antennas: they can be configured so many different ways.

If you’re interested in the CHA TDL, I’d strongly encourage you to read though the user manual: it’s chock full of info and ideas. Click here to download as a PDF.

Next time I take the CHA TDL out, I think it’ll be to a summit where I’d like to see how it might perform on the higher bands with the ground sloping away from the antenna site.

Click here to check out the CHA TDL at Chameleon Antenna ($355 US shipped).