After sharing a few photos by request comparing the size of the Mountain Topper MTR-3B, MTR-4B, and Elecraft KX2 yesterday, I took a few pmore photos by request comparing those same radios with the Elecraft KX1.
I decided to simply post these on QRPer.com in case they could also be of help to someone else:
A reader/subscriber just asked for photos comparing the size of the Mountain Topper MTR-3B and MTR-4B. I know they were also curious how the MTR-4B might compare in size with the Elecraft KX2. Of course, one can look up the actual sizes, but sometimes a photo adds more context.
I decided to simply post these on QRPer.com in case they could also be of help to someone else:
A question I’ve received several times since sharing my last field activation with the MTR-4B is “why do Mountain Topper radios have three individual band switches–?”
That’s a great question and the answer is actually in the product manual.
The following comes from the MTR-3B manual but also applies to the MTR-4B (save the 4B has four band positions instead of three):
The band is selected by three, three position slide switches. For proper operation, all three switches must be in the same
column[…]. It’s easy to get into the habit of flipping each switch in sequence from the top down.
The top switch tells the processor which band to operate on and connects the Receiver input filter to the first mixer. The
middle switch connects the transmitter low pass filter output to the antenna and connects the antenna to the receiver
input filter. The bottom switch connects the output of the transmitter PA to the low pass filter.
The manual is correct: it’s easy to get in the habit of sliding all three switches with band changes. It becomes second nature in very short order.
It’s easy to tell that all of the switches are in the correct position as well because without all three switches selected, the receiver sounds deaf and audio muted. With them in position, the receiver sounds “alive.” (That said, the noise floor is so low on these radios, it’s quite possible you might think they’re not engaged properly if there aren’t many signals on the band!) Of course, it’s very easily to visually inspect the switches and confirm they’re in the correct position.
Side note: On the Mountain Topper series, each band switch is an independent mechanical switch. On the Venus SW-3B (which was no doubt inspired by the Mountain Topper) the two band switches are bound together as one:
You can’t tell from looking at the photo above, but if you slide the top switch, you’re also sliding the bottom switch: the two switches are only one mechanical piece. An interesting design choice!
Side Note: The (now discontinued) Mountain Topper MTR-5B had a more complex series of six switches. Here are the instructions for it along with a drawing from the MTR-5B manual:
I hope this helps clarify how/why the Mountain Topper series uses multiple switches for band changes!
The entire time I was in Canada this summer–about two months–I used two field transceivers: the Elecraft KX2 and the Discovery TX-500.
I did sneak in two extra radios under the floor of my trunk/boot space, but they both were limited to three watts and conditions were so rough during many of my activations, I wanted the option of a QRP “Full Gallon” (5 watts). Thus, I stuck with the TX-500 and KX2 (which are both actually capable of 10 watts output).
When I got back to the States, I was eager to do a POTA activations with my other radios–many of you know I like to rotate them–but there was one, in particular, I was eager to put back on the air…
This MTR-4B V2 is on loan to me from a very generous reader/subscriber. In fact, get this: he ordered the MTR-4B early this year and had it drop-shipped to me directly from LnR Precision. He knew I’d be in Canada for the summer, so has been incredibly flexible with the loan period (basically leaving it open ended).
My review of the MTR-4B will be published in the November or December (2022) issue of The Spectrum Monitor magazine. Then I’ll be sending the MTR-4B to its rightful owner!
In the meantime, I built an ultra- compact field radio kit around the MTR-4B and in my Tom Bihn HLT2 EDC pouch.
This kit is nearly identical to the one I made for my MTR-3B (just a different color, really).
It contains the radio, a battery, an antenna (although I used a different one during this activation), fused power cord, paddles, earphones, RF choke, RG-316, logbook, pencil, and even a full throw line and weight. I’ve listed all of the components with links below.
It’s hard to believe it all fits in such a compact kit and it works so well. It’s nice to know that with the kit it in my backpack, I’ve got everything I need to play SOTA or POTA at the drop of a hat.
On August 8, 2022, I drove to my hometown to check in on my parents. I didn’t have a lot of time, but I wanted to fit in a quick activation with the MTR-4B along the way.
One of the easiest parks for me to hit en route is the South Mountains State Park Clear Creek Access–it’s maybe a 10-15 minute detour off of Interstate 40.
The weather was amazing that day, although I’ll admit I had to get used to the heat and humidity after spending so much time in Canada this summer!
This access point of South Mountains only has one picnic table. I’m always prepared with a folding chair if that table is occupied, but so far it’s always been available. I’m sure the reason is because this particular South Mountains access point is way less popular than the main entrances. Most of the visitors here come to fish at the reservoir.
The great thing about having your whole station in a pouch is that setup is quick and easy.
Many thanks to Matt (W7MDN) who writes:
When I was first getting into Ham radio a couple years ago, I ran across a slide presentation done by Fred KT5X on “Ultra-lyte” QRP. In it, Fred has pictures of a trail running hydration vest that contains a complete SOTA station, water, snacks and a jacket. I was sold on the idea, and made it my goal to start making my own ultralight setup.
Click here to download KT5X’s original presentation (PDF).
As time went on, I really got into the ultralight approach to SOTA, taking every opportunity to reduce weight and shrink my pack down. I enjoy some trail running, mountain biking and combining SOTA/POTA with either is the ultimate combo of adventure and ham radio. Continue reading Matt’s “Ultra-Lyte” Hydration Vest QRP Field Kit
As you might have noticed from past field reports, I’m a big fan of the LnR Precision Mountain Topper MTR-3B. It’s a wee CW-only transceiver that is almost perfectly designed for summit and park activating. It’s so lightweight and compact, you barely notice it in your backpack.
Thing is, the MTR-3B is no longer produced and I’m not sure if it ever will be again, but Steve Weber (KD1JB) hasn’t stopped making iterative improvements to the Mountain Topper design and LnR hasn’t stopped producing them.
In late 2020, LnR introduced the new MTR-4B which replaced the MTR-3B and added a few extra features that many of us had been asking for including:
The MTR-4B also has an attractive red gloss chassis.
And the right and left sides of the chassis even protrude a bit to better protect the front panel buttons and switches when the unit is flipped over on its face. Nice touch!
One of the great things about being me is I am often at the receiving end of incredibly generous people who like supporting what I do.
QRPer.com is a pure labor of love and I’d do what I do without any compensation, but it’s an honor when anyone goes out of their way to thank or support me.
Seriously: the kindness I feel here restores my faith in humanity.
In January, a reader (who wishes to remain anonymous) approached me with a deal I simply couldn’t refuse. He is a very seasoned and accomplished field operator but has only recently been upping his CW game. I believe as a reward to himself for starting CW activations later this year, he told me he wished to order a new MTR-4B.
What he proposed was to purchase the radio from LnR and have it drop-shipped to me. He wanted me to have the opportunity to review this little radio and log field time with it as well. He told me I could use it for months before shipping it to him and not to worry about it getting scratched or showing other signs of field use.
Wow.
I loved this idea because, as a reviewer, it isn’t financially viable to buy each and every radio I would like to review. I do like asking manufacturers for loaner radios, but LnR is a small manufacturer and make these units to order. I know them quite well and they simply don’t have extra loaner units lying around the shop–much like new automobiles these day, each one produced is already spoken for.
I accepted his offer with gratitude. I looked forward to getting my hands on the MTR-4B!
But that wasn’t all: this kind reader has actually been sending me coffee fund contributions that will add up to half the price of a new MTR-4B should I decide to purchase and add one to my own field radio arsenal! I tried, but I couldn’t talk him out of it.
So there you go. I’m so incredibly grateful.
As LnR Precision states on their website, there’s roughly a 6-8 week lead time on the MTR-4B. I took delivery of this unit in early March.
As with all LnR Precision products, it was packed amazingly well.
I wasn’t sure what to expect in terms of size, but the MTR-3B is only slightly bulkier than the MTR-3B (indeed, in my activation video below, I compare the two).
I love the hotrod red paint job!
This unit arrived during what turned out to be a crazy time for me–one where there was nearly a four week period with no field activations. That’s how crazy!
I did play with the MTR-4B in the shack, however, during that time and logged numerous POTA, WWFF, and SOTA activators. I even had a couple of 80 meter rag chews.
Many field ops were surprised that the MTR-4B didn’t use the forth band position for 17 or 15 meters and I tend to agree. In the field, efficient 80 meter antennas are a bit bulky for the likes of a summit activator. Then again, when in the shack or for extended camping trips? I find 80 meters a brilliant band for evening rag chews and late night DXing.
Not sure how much I’ll use 80M in the field, but I do appreciate this additional band!
Of course, the MTR-4B is built for playing radio outdoors and that’s exactly what I had in store for it on April 13, 2022. Continue reading My first POTA activation with the Mountain Topper MTR-4B V2