Amazing Fun with 3 Watts: Pairing the MTR-3B, T1, Speaker Wire, and a 9V LiFePo4 battery at South Mountains

I’ve been spending more time with my Mountain Topper MTR-3B (“Tuppence”) recently and have been thoroughly enjoying this little radio’s companionship.

Since I made a dedicated ultra-compact field kit for the MTR-3B, it has also been even easier to toss it in my backpack and take it on little field adventures. The field kit is truly a grab-and-go and even includes a throw line and weight.

On Friday, January 28, 2022, after a total of six individual park activations during the previous two days (a POTA RaDAR run and my first 2020 Antenna Challenge activation) driving back to the QTH I thought, “surely I can skip doing an activation today.

That quickly turned into, “Wait a minute…I’ve got enough time to fit in both an activation and a hike!

So I made a quick detour off of I-40 to visit the Clear Creek access of South Mountains State Park.

South Mountains State Park (K-2753)

I pulled into an empty parking area; not really a surprise on an early Friday afternoon. In addition, I figured many were out grabbing bread and milk since winter weather was in the forecast.

I decided to do my activation first, then pack up and take the full kit on a hike.


I’ve divided up the gear section to list the full contents of my MTR-3B kit even though I used a different antenna on this activation than the one in the kit. The main additions to the kit this time were the Elecraft T1 and speaker wire antenna (the T1 is needed as the MTR-3B has no internal tuner).

MTR-3B Ultra-Compact Field Kit:

Other Gear:

Looking at the long gear list, you’d think you’d need a big pack for them, but it’s quite the opposite. All of this takes up little space and I’d certainly not need the tactical backpack for this activation, but I chose it knowing I’d hike later.

I do love this field kit!

Deploying the antenna was very easy. I actually include this in the activation video (see below).

On the air

Since I had the T1 ATU, I knew I could work all of the MTR-3B’s three bands: 40, 30, and 20 meters.

I started on 40 meters, called CQ POTA and worked eight stations in 7 minutes. A great start!

Next, I moved up to the 30 meter band where I worked an additional four stations in 3 minutes.

Between the 40 and 30 meter bands, I had validated my activation (10 contacts) in 14 minutes. Woot!Next, I moved to the 20 meter band where I worked eighteen stations in 21 minutes.

20 meters was definitely the winner that day!

Here’s my full log sheet for your reference (a cheat sheet if you copy code in my videos):


Here’s what 3 watts into a speaker wire antenna can yield in a total of 41 minutes on the air (click to enlarge):

Activation video

Here’s my accompanying real-time, real-life activation video. As always, my videos have no edits during the activation. In other words, you get to see all of my mistakes in amazing HD video quality!

Click here to view on YouTube.

A quick post-actie hike

Even thought the car was close by and I could stash my SOTA pack prior to hiking, I wanted to hike with my full radio kit in the Spec-Ops Pack. One reason I like doing this besides the extra pack time is that it also contains my first aid kit and other emergency supplies.

I took the Clear Creek trail which is a 2.5 mile out-and-back trail. When I was very close to the end of the trail, I ran into another hiker–and older gentleman who lived only a couple miles from the park.

He started talking to me before I even approached him, as if he’d been waiting on me to arrive for some time. It was great, actually, because on the hike back, he took me off-trail to point out a number of old home sites.

I’ve always enjoyed finding little home sites in the forest and it amazes me how the stone chimneys (or “chimblies” as we’re raised calling them in the foothills) seem to stand the test of time.

In the spring, homesites are easy to find because daffodils pop up around the perimeter of former home sites.

He chatted with me all the way back to the car. He was good company and I was happy to soak in a little of his local knowledge.

Thank you

Thank you for reading this field report and I hope you can fit in a little time to play radio in the week ahead!

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.

Have a wonderful week, friends!


Thomas (K4SWL)

3 thoughts on “Amazing Fun with 3 Watts: Pairing the MTR-3B, T1, Speaker Wire, and a 9V LiFePo4 battery at South Mountains”

  1. I keep looking at getting one of the A PackTenna Mini 20M EFHW antenna.

    got email saying was again stock, went to site and could not add to cart as if they are not in stock.

    It must be good. I am going to try one i made, is simple.

    73, ron, n9ee/r

  2. Great post and video Thoma. Thanks.

    I’m curious how well that battery would work with the Xiegu X6100. The internal battery is only 8 volts and I’m curious how long the 9V Bioenno would work and if the 6100 can do 10 watts on the 9 volts.

    Have you tried it?

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