Tag Archives: N6ARA MiniSWR

Field Radio Kits, Grab And Go, News, Portable, POTA, QRP, QRP Radios, SOTA

Deep Dive: My Mountain Topper MTR-3B Watertight SOTA Field Kit

5 Comments

Last week, in response to a reader’s question here on QRPer.com, I was reminded that I hadn’t yet made a video specifically about my Mountain Topper MTR-3B SOTA field kit.

Yesterday, I made a short video (see below) where I show what I pack in my MTR-3B field kit and why I choose to house it in a Pelican 1060 case.

First, let’s look at a list of the gear, then I’ll talk about what went into my choices, and I’ll link to the video.

Gear:

Note: All Amazon, CW Morse, ABR, Chelegance, eBay, and Radioddity links are affiliate links that support QRPer.com at no cost to you.

Self-Contained Watertight Field Kit:

Optional Gear for SOTA/POTA:

Design Choices

Here’s the philosophy behind my design choices in this kit:

Pelican 1060 Case

I chose to house this field kit in a Pelican 1060 Micro Case even though, at one pound, it weighs more than the typical pouch I also use for small field radios. The Pelican, however, protects the entire radio kit as it’s fully watertight and crush-proof. If I trip while fording a creek or fall and land on my pack, the Mountain Topper will be safe. Yes, there’s a mass/weight cost, but I feel it’s very minimal for the protection it offers.

Counterpoise-less End-Fed Half-Wave

When I build the K6ARK EFHW antenna kit for my MTR-3B, I chose to make it without a counterpoise. Even though the antenna would be more efficient with a dedicated counterpoise and less prone to the effects of body capacitance, I feel like the benefits of this design outweigh the compromises. For one thing, leaving off the counterpoise saves space inside the Pelican case. In addition, by designing the antenna to attach directly to the MTR-3B’s BNC port, there’s no need to include a feedline, thus saving quite a bit of space.

So far, I’ve been very impressed with how forgiving this antenna has been and, most importantly, with how well it has performed.

N6ARA SWR Meter

I include the N6ARA MiniSWR  in my field kit to give me some peace of mind if my antenna deployment is compromised (for example, if the trees on a summit are too small, etc.). Since my MTR-3B version has no built-in SWR metering, I feel this is a meaningful addition tot he kit.

Throw Line and Weight

At least 90% of the summits and parks I activate here in western North Carolina have trees. To me, no field kit is truly sufficient unless I include a throw line and weight. I find that the Marlow KF1050 Excel 2mm Throwline is small, lightweight, and effective—-25 meters is enough to deploy any wire antenna I’d carry on a SOTA activation.

Many SOTA ops use a small sack that they place stones in to act as a throw weight for their line. This is very clever because you don’t have to pack in that extra 8 ounces on the roundtrip hike. Still, I like the convenience of a throw weight that’s designed to glide through tree branches with ease–especially if the tree is dense. If I were to do a multi-day SOTA backpacking trip, I’d probably use an empty throw sack instead of a dedicated weight.

Rechargeable 9 Volt Battery Packs

I love these 9V rechargeable batteries. It’s hard to believe that the MTR-3B can complete 2-3 typically SOTA activations on one charge! Then again, the MTR-3B uses something like 18ma in receive? That’s crazy low current consumption. These batteries are super lightweight and the particular brand I use has never produced any RFI (I’ve read that some others can). What’s best is that I can recharge these easy via a USB-C cable.

The MTR-3B will operate on nine volts, which yields three watts of output power.

Helinox Chair and Kneeboard

Yes, these are luxury items. I know many SOTA ops who are quite happy to sit on the ground and balance their radio on their leg. Perhaps it’s my age, but I don’t like doing this anymore because my legs tend to fall asleep and I lose feeling in them if not careful.

My Helinox Zero chair weighs 1 lbs 2 oz (509 g). I feel like it’s weight and mass well-spent. Since I record activation videos, the chair also gives me a much better position for my camera angle (bonus!).

My Tufteln/N0RNM kneeboard is an essential part of my SOTA kit. I never leave without it. The chair and kneeboard combo gives me the flexibility to set up anywhere, anytime. I love it.

Video

Here’s a video showing the breakdown of my Mountain Topper MTR-3B SOTA field kit:

Click here to view on YouTube.

Thank you!

 

Thank you for reading my field kit post and watching the video! I hope you enjoyed it.

As always, I’d also 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 not a requirement, as my content will always be free, I really appreciate the support.

If you’d like to see loads more field kits, check out our field radio kit gallery!

Thanks for spending part of your day with me!
Cheers & 72,
Thomas (K4SWL)