Field Report: Pairing the Discovery TX-500, Elecraft T1, and CHA MPAS Lite

You might recall that I’ve been testing a new backpack that I plan to use primarily for SOTA activations. It’s the Spec-Ops Brand T.H.E. Pack EDC.

I’ve now taken it on a few activations, but the very first outing was on Monday, December 7, 2021.

That afternoon, my daughters attended an afternoon art class that was only four miles from our QTH as the crow flies, but took 45+ minutes to drive. Gotta love the mountains!

I had no complaints whatsoever about the drive, though, because it was within five minutes of the Zebulon Vance Historic Birthplace; one of my favorite local POTA spots!

Zebulon B. Vance Birthplace (K-6856)

After dropping off the girls, I drove to Vance and was happy to see that no one was occupying their one picnic shelter. Even though the Vance site is relatively spacious and they’ve numerous trees along the periphery of the property, it’s a historic/archaeological site and as a rule of thumb I only set up at picnic areas in parks like these.

It was a breezy day and temps were hovering around 44F/7C. These are ideal conditions in my world.

I grabbed the Discovery TX-500 for this activation. I had been using it quite a bit in the shack, but realized I hadn’t taken it to the field in a few weeks. I decided to pair it with the Chameleon MPAS Lite vertical antenna since I had already loaded the Lite in my pack, using the pack’s built-in antenna port.

While I knew this activation wouldn’t include any hiking, it did give me an opportunity to pack-out my new backpack and see how it would accommodate a typical field set-up.


Setup was incredibly easy and fast–this one of the reasons I love the Chameleon verticals so much. Simply attach the matching unit, whip, and counterpoise to the stainless steel spike, push the spike into the ground, extend the whip and deploy the counterpoise roughly 25′. Done.

While one might give up a bit of efficiency using a non-resonant vertical, you gain more on-the-air time because setup is so simple and speedy. In addition, band changes are effortless and quick. I prefer the MPAS Lite over my Wolf River Coils TIA for this reason. Both are great antennas, but when I’m in a hurry, I dislike tweaking the coil on the WRC antenna during band changes. (This reminds me that it’s time to take the WRC to the field again!)

On the air

I knew in advance that this would be a very short activation. My daughters were only at their meeting for an hour or so and my wife and I wanted to fit in a little stroll around the Vance property as well.

When in a hurry, I always start on 40 meters. It tends to be the most productive band for park activations in North Carolina–no doubt because there are a large number of POTA hunters within my 40 meter footprint.

I started calling CQ and within 13 minutes had validated the activation with 10 contacts.

I stayed on the air an additional  7 minutes and worked 5 more stations.

Many thanks to KE8ONI for that Park-To-Park!


It’s fascinating looking at contacts on a map. In this case, it looks like the pattern strongly favored a path to the north and northeast. About half of the contacts were in the DC to NYC corridor.

Activation Video

I recorded a real-time, real-life video of my entire activation. As with all of my videos, this one is unscripted and unedited.

Click here to view on YouTube.

I’ll be the first to admit that when I review my videos before uploading, there are often “wince-worthy” moments.

In this case, I noticed how I kept repeating a keying error over and over!

It’s a great reminder that CW is very much an operation in muscle memory. I remember now that as I kept repeating the error, it was as if my fist had a mind of its own. In truth, I think a lot may have to do with the fact that I switch out radios so often. There are often negligible differences in electronic keyer timing between radios and I believe that can trip up my fist.

I always liken it to driving manual transmission cars. Even though I’ve driven them my whole life, when I get into a new manual transmission car it often takes a while for my muscle memory to adapt to the different clutch depth and stick throw. Those first few minutes in a new vehicle, my shifting is less fluid, I might ride the clutch a bit when stopped on a hill, and I could even grind the gears a bit (cringe!).

We all have days when our keying isn’t stellar. Forgive yourself when this happens.

Thank you!

Thanks for reading about this rapid field activation!

Keep in mind: you don’t have to set a full day aside to do an activation. If you have a hankering to play radio in the field, perform a rapid activation.  Don’t even worry about logging the 10 contacts needed to validate a park activation. Just do what you can in the amount of time you have! I believe my rapid activations actually help hone my deployment and packing skills.

Hmmm…there might be another article in this. Stay tuned!

I’d like to send a special thanks to those of you who have been supporting the site and channel through Patreon and the Coffee Fund. While certainly not a requirement as my content will always be free, I really appreciate the support.

Cheers & 73,

Thomas (K4SWL)

13 thoughts on “Field Report: Pairing the Discovery TX-500, Elecraft T1, and CHA MPAS Lite”

  1. Hi Thomas, as always, thank you for your videos and detailed set-up.

    If you don’t mind, I would like to ask your opinion about a cheap set-up to use of the field. I have an IC-705 with the tuner AH-705. I was thinking in building a cheap MPAS-like setup without the coil, using a long fishing rod with a spike, a wire to be raised with the rod (wire parallel to a non-conductive rod, as a mast), and another wire as counterpoise, using the AH-705 at the rod base (or farther using coax). Do you think it would work? It will tune at least in 40m and shorter wavelengths, that for sure, but I don’t know if it will also work (that is, hear and be heard), or if the coil at the base is a must.

    Thank you!

    1. I should think the setup you’re talking about would work brilliantly. In a sense, it would be similar to how I deploy my 28.5′ speaker wire antenna. I typically hang the radiator wire vertically and use only one counterpoise. All of my ATUs can find matches on 40M and higher. Having the ATU at the antenna is a great practice and that is a huge plus with the AH-705. If you add a couple more counterpoises (at least 17 feet), all the better.

      By combining the telescoping rod, you’d make the whole system self-supporting. I think you could get away without using a coil–the AH-705 should handle the match, no worries.

      Let us know how it goes!


  2. I love my TX-500 and it’s due for an outing. When you first sent your callsign, you changed to L to the Prosign AS which means Wait. I am just a wealth of useless information. I have a X6100 due here tomorrow (I hope). I hate bad finger days. I have been playing with Begali’s CW Machine and using a keyboard to send code. I does a good job. It also logs for me. So far I’ve hunted with it but I may take it on an activation soon.

    1. Ha ha! I look forward to hearing how you implement the Begali machine in POTA! I have a lot of bad finger days. The worst is when I change rigs in the shack and do casual hunting–there are days I can’t send my callsign correctly. 🙂

  3. Great blog article, thank you.
    Yes I’m trying to keep my mind open to just getting out there. Only 10 needed for activation, so why not get out there.

    I’m looking at your spec op bag and considering one, hopefully soon, though in multicam which I don’t mind, looks like they are out of several other ‘patterns’
    Thanks again & 73

    1. Their inventory has been low, like a lot of other US manufacturers. The MultiCam is a great pattern!

  4. Another great article trying to decide on whether to buy the TX-500 but already have a KX3 and IC705 not sure if it would get much use , shame the bag isn’t available in the UK looks ideal and just what I have been looking for

    1. That’s disappointing that Spec-Ops can’t ship to the UK. I would have thought for sure.

      Honestly? With the KX3 and IC-705, there’s no real reason to grab a TX-500 other than for the fun factor and weather-proofing. Both of those rigs outperform it on the bench.

    2. Hi Andrew, a bag to consider (I ordered mine direct to Doncaster, from the manufacturer) is a Red Oxx Gator EDC. Excellent and robust construction and readily houses my entire TX500 based station or my KX3 equivalent.

      1. That’s brilliant to know that Red Oxx ships to the UK. The Gator is an excellent choice!

        I would only add that the Gator is not a backpack, so if you’re planning to do SOTA, you might go for a backpack style bag. For anything/everything else, the Gator would serve you well. I really like the exterior pockets on the Gator,

  5. I have been using Kyle’s POTA Logger software and it makes sending in a log super easy even if I have to transfer from paper to the computer after the fact. Sending in the log was one of the reasons I hesitated to do an activation but with POTA logger it is worth activating even if you don’t make 10 contacts.

    You can get it free here:


  6. I recently bought a set of CW Morse Pocket Paddles just like yours. I think they’re very nice, especially for the price. He has upgraded the design a bit and they now come with a tension adjustment in addition to the spacing adjustment (that’s not yet shown on the website). I’ve used my on a couple of activations and a few backyard ops with my KX2. 73 de KR8L

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.