Many thanks to Mike (2E1BFH) who shares the following photos of a new field kit he’s built around the Icom IC-705:
Continue reading Photos of Mike’s uber-organized Icom IC-705 field kit
Category Archives: QRP Radios
Ken’s photos comparing five field radios
Many thanks to Ken (WW5A) who writes:
Hello Thomas-
I enjoy reading the posts on the QRPer. The size comparison photos recently posted got me thinking. I had taken a photo several months back of a X5105, 817, RS918 (McHF), G90 and a 705, basically to do the same thing (size comparison).
I have attached them for your amusement [click to enlarge]:
73,
Ken WW5A
Thanks for sharing these, Ken. To me, it’s interesting to see the comparison between the FT-817 and the G90. When I owned a G90 I didn’t have an 817 at the time for comparison. It reminds me just how long/deep that G90 was! Also interesting to see that the mcHF clone is a wee bit wider than the IC-705. Thanks for sharing!
Photos: Comparing sizes of the Mountain Topper MTR-4B, MTR-3B, and Elecraft KX1
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:
Mountain Topper MTR-3B v Elecraft KX1
Mountain Topper MTR-4B v Elecraft KX1
Elecraft KX1 v KX2
Photos: Comparing sizes of the Mountain Topper MTR-4B, MTR-3B, and Elecraft KX2
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:
Mountain Topper MTR-4B vs MTR-3B
Mountain Topper MTR-4B vs Elecraft KX2
Why does the Mountain Topper MTR-4B (& 3B) have three separate band switches?
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 FX-4L QRP SDR HF transceiver is on order!
This year, I’ve had a couple of readers very kindly offer to loan me their FX-4C transceivers to take to the field and review.
Those offers have been very temping because I’ve only heard positive comments from owners of this wee feature-packed SDR transceiver designed by Yu (BG2FX).
Earlier this year, I learned that Yu was retiring the FX-4C and would be introducing two new radios, so I decided to hold off on an FX-4C review for this reason.
My buddy, Don, informed me that the new radios were now available for pre-order, so I checked out the option on Yu’s website, and placed an order.
Details (features and specs) are still a little sparse because BG2FX is still finalizing the design and lining up production, but here’s a snapshot of the two models based on Yu’s preliminary info:
The FX-4CR
I was very pleased to read that my buddy John (AE5X) has one of these on order.
The FX-4CR can push 15-20 watts on most bands according to John, which is most impressive for a one pound radio that fits in the palm of your hand! It covers 80 – 6 meters, sports a color screen with a 48 kHz wide waterfall display, an internal sound card for digital modes, built-in speaker and microphone, 9 – 18 VDC input range, and even sports Bluetooth!
That’s an impressive array of features for $550 US (on pre-order).
The FX-4L
I pre-ordered the FX-4L and am told by Yu that it should ship by end of October or early November 2022. I wouldn’t be surprised if that’s an optimistic projection.
The FX-4L is essentially a more basic QRP version of the FX-4CR; it’s maximum output power is around 5 watts.
It’s very similar to the FX-4CR in many respects: it has the same display from what I can tell, covers 80 – 6 meters, has a wide voltage range 9 – 18 VDC, sports an internal sound card, and is super compact and lightweight.
The FX-4L doesn’t appear to have Bluetooth. Lu doesn’t mention a built-in speaker or microphone, but there’s an obvious speaker grill and even a small hole that might be a microphone. I’ll try to confirm this. Yu does note that there’s room in the chassis for the user to add a battery or ATU.
I’ve been more interested in the FX-4L because, as you likely know, it’s very rare for me top operate over 5 watts of power.
That said, I certainly see the appeal of a 15W+ radio like the FX-4CR.
(Many thanks to Yu for sharing all of the FX-4L photos above.)
Stay tuned!
I’m really looking forward to checking out the FX-4L and also reading AE5X’s assessment of the FX-4CR.
I’m curious if anyone else has pre-ordered one of these radios. Also, if you’re an FX-4C owner, I’d love to hear your comments!
What are my favorite QRP field radios in terms of audio quality–?
Many thanks to QRPer.com reader, Charles, who recently sent me the following question:
Thomas, I’ve watched a number of your videos and read your activation reports. I’m studying for both my Technician and General class license right now and hope to pass both in one session later this month. I’m also learning CW.
I consider myself an audiophile and appreciate good audio fidelity. I know that amateur radio modes are narrow and by their very nature have less audio fidelity than commercial broadcast modes.
I’ve already obtained a Kenwood TS-590G for the shack. It was practically given to me by a friend. I’m very pleased with its audio fidelity especially when I connect it to an external speaker.
Next year, I plan to buy a dedicated QRP field radio. Out of the radios you’ve owned, what are your favorites in terms of audio fidelity. Also, what are your least favorites?
Thank you.
What a great question, Charles!
Being an audiophile, I’m sure you understand that this is a very subjective area: one person’s idea of good audio might not match that of someone else’s.
I can only speak to how I evaluate a transceiver’s audio.
What makes for good audio?
A lot goes into what I would call “good audio” in an amateur radio transceiver.
To me, “good audio” means the radio
- produces clear accurate sound,
- has stable AGC (Auto Gain Control),
- has audio properties that benefit amateur radio modes like CW and SSB,
- has enough audio amplification to be heard in noisy field conditions,
- and has little to no internally-generated noises leaking into the audio amplification chain. (In other words, a low noise floor.)
In contrast, radios with poor audio
- sound noisy/harsh,
- have a high noise floor or produce audio hash making it difficult to hear weak signals,
- have speakers that become distorted at higher volume levels,
- have poor AGC characteristics which lead to pumping,
- and are simply fatiguing to listen to during extended on-air sessions (like long activations or contests).
I would add that a good receiver front end is an important part of audio because it keeps imaging and overloading at bay, thus producing a less cluttered and noisy audio experience.
My field audio favorites
I’ll keep this discussion limited to QRP field portable radios. There are numerous 100 watt desktop radios with excellent audio because those models aren’t trying to limit their current consumption like field radios typically do. They can use more amperage to benefit audio amplification and push a much larger speaker.
In addition, I’ll limit the scope to field radios with built-in speakers. There are some great CW-only radios out there that lack an internal speaker but have great audio (thinking of the Penntek TR-35 and the Elecraft KX1, for example); choice of earphones or headphones can have a dramatic effect on audio. That’s a different discussion altogether!
Best audio: My top three picks
The following are three of my favorite portable field radios in terms of audio quality. I limited myself to three simply because all of the radios I use regularly in the field have what I would consider good and acceptable audio.
The following are simply stand-outs, in my opinion:
Continue reading What are my favorite QRP field radios in terms of audio quality–?
Taking the Mountain Topper MTR-4B on a quickie activation at South Mountains State Park!
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…
The Mountain Topper MTR-4B.
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.
South Mountains State Park (K-2753)
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.
Setting up
The great thing about having your whole station in a pouch is that setup is quick and easy.
The New Penntek TR-45L: A Video Tour/Overview, then a full POTA activation!
Yesterday, John (WA3RNC) opened orders for his long-awaited Penntek TR-45L 5 band, CW-only, QRP transceiver.
As I mentioned yesterday, I’ve had the pleasure of helping John beta test this radio for the past month. In that time, I’ve gotten to know the radio from the inside out and have even taken it on a few POTA activations. In fact, with John’s permission, I just posted my first TR-45L activation video for Patreon supporters yesterday. The radio was using an early firmware version in that video.
TR-45L Video Tour and Overview
Yesterday, after an early morning appointment, my schedule opened up; a rarity in my world.
I then got the idea to take the TR-45L out to a park, do a full video overview of its features, then put it on the air in a POTA activation.
Hazel loved this idea too.
So I packed the TR-45L, a log book, my throw line, and two 28′ lengths of wire. Hazel jumped in the car before I could invite her.
I’ve used a wide variety of antennas on the TR-45L over the past weeks, but I hadn’t yet performed a park activation only using two lengths of wire and relying on the TR-45L’s optional Z-Match manual antenna tuner. This would make for a great real-life test!
Quick note about video timeline
Side note for those of you who follow my field reports and activation videos…
I pushed this video to the front of the line since the TR-45L just hit the market. I wanted to give potential buyers an opportunity to see and hear this radio in real world conditions thinking it might help them with their purchase decision.
I’m currently about 7 weeks behind publishing my activation videos. Much of this has to do with my travel schedule, free time to write up the reports, and availability of bandwidth to do the video uploads (I’ve mentioned that the Internet service at the QTH is almost dial-up speed).
I was able to publish this video within one day using a new (limited bandwidth) 4G mobile hotspot. Patreon supporters have made it possible for me to subscribe to this hotspot service and I am most grateful. Thank you!
So that I can publish this report quickly (this AM), I’m not going to produce a long-format article like I typically do. Instead, this is one of those rare times when the video will have much more information about the radio and the activation than my report. I’ve linked to and embedded the video below.
Now back to the activation…
Continue reading The New Penntek TR-45L: A Video Tour/Overview, then a full POTA activation!
Introducing the new Penntek TR-45L
If you’re a fan of the Penntek TR-35 or its predecessor, the TR-25, I’ve got some good news for you.
John (WA3RNC) announced this morning that he is now taking orders for his latest design: the long-awaited TR-45 Lite (TR-45L).
I’ve been helping John Beta test this radio since mid-August. I’ve activated a number of parks with it and have used it almost exclusively from home.
In short? I really love it.
Here’s the announcement John (WA3RNC) has posted on his website along with a form to fill out if you’re interested in purchasing from the first run. John notes:
The TR-45L 50-unit pilot run construction is now underway! These first units will be factory wired, tested, and aligned. These units will be available for shipment over the next several weeks. The plan is to have kits available in about 6 to 8 weeks. The kit price is expected to be $430.00. Please understand that this will not be a kit for beginners…
Pricing has been set at $580.00 for wired and tested pilot run units, with an additional charge of $22.00 for USPS Priority Mail shipping. There are two available options: The first is an internal 5200 MAH Li-Ion battery pack and charger with a price of $80.00, and the second is an internal Z-Match antenna tuner for easy matching in the field to simple wire antennas. The Z-Match tuner option is priced at $60.00. Note that the Z-Match ATU can be added later but will require that you drill some rather precise holes in the back case housing and a do a bit of soldering. [Continue reading…]
This radio is pricier than the TR-35, of course, but I would argue it’s very well worth the money: the receiver and audio are superb. The radio has a fun factor that’s hard to describe.
I’ve just updated the radio with the latest firmware and will be taking it on an activation this morning (Monday, Sep 26, 2022). Check the POTA spots page for me.
I’ll make a video including a full tour of the radio, then perform the activation. If the hotspot bandwidth gods are on my side, I may have this posted later today or early tomorrow.
Note that John (AE5X) has also been testing the TR-45L and will also have updates and videos.
The upshot?
If the TR-45L looks like the sort of radio you’d enjoy taking to the field, just go ahead and get one. I think it’s brilliant.
I suspect his first production run will sell out in very short order.
It’s a simple radio with simple–almost Apollo era inspired–controls. The audio is gorgeous and I’m pleased with the filtering options. The internal battery option will power it for ages and the Z-match tuner options works beautifully.
Again, if you want to hear it on the air, check the POTA spots for me sometime between 16:00-18:00 today!
Stay tuned!