Tag Archives: LNR Precision

A review of the Par EndFedz EFT-MTR triband antenna

Note: the following post originally appeared on our sister site, the SWLing Post.

The Par EndFedz EFT-MTR triband (40/30/20M) antenna

In July, I purchased a tiny QRP transceiver I’ve always wanted: the LnR Precision MTR-3B. It’s a genius, purpose-built little radio and a lot of fun to operate in the field.

It’s also rather bare-bones, only including a specific feature set built around ultra-portable CW operation.

While the MTR-3B has features like CW memory keying, a wide operating voltage (6-12 VDC), extremely low operating current (20 ma in receive), real-time 24 hour clock, and a full compliment of keying adjustments, it lacks other features like a volume control, SWR meter, speaker, and built-in antenna tuner.

Some of those may seem like big omissions but SOTA and POTA activators who like extremely lightweight/portable gear love the MTR-3B for being so purpose-built.

The MTR-3B (and its predecessors) operate on three bands: 40, 30, and 20 meters. These are, without a doubt, my favorite bands when operating portable since antenna lengths are reasonable.

Since the MTR-3B doesn’t have an internal ATU, you need to pack an external tuner or, better yet, a resonant antenna–ideally, one that can be used on all three bands.

Although many of my portable transceivers have built-in ATUs, I rarely use them because I primarily operate with resonant antennas. Resonant antennas are more efficient–giving you the maximum mileage per watt. In addition, they’re also more simple: connect them to the rig and hop on the air. No tuner or tuning required.

Since I keep self-contained field radio kits, my MTR-3B needed a dedicated resonant antenna.

The EFT Trail-Friendly antenna is incredibly compact and quite easy to deploy.

I’ve mentioned in previous posts that I’m a big fan of the Par EndFedz Trail-friendly EFT tri-band antenna (above) which is resonant on 40, 20, and 10 meters.  I’ve activated well over 130 parks with this little antenna.

After I took delivery of the MTR-3B, I borrowed the Trail-friendly EFT antenna from my KX2 field kit. It worked well on 40 and 20 meters, but it doesn’t cover the 30 meter band. Also, by borrowing the EFT from the KX2 kit, I broke one of my rules: never borrow from one field kit to feed another. This led to me leaving the EFT hanging in a tree at a remote park and returning a week later–a three hour round-trip(!!!)–to retrieve it. (FYI, in all fairness, I also blamed my trusty canine companion for this mishap!)

Enter the Par EndFedz EFT-MTR triband antenna

A few months ago, Vibroplex purchased the Par antenna line from LnR Precision.

I was very pleased with this decision as I’m guessing LnR Precision wanted to hand off antenna production so they could focus on the very popular Mountain Topper transceiver line.

Vibroplex is owned by my buddy, Scott Robbins (W4PA), who is not only a successful entrepreneur, but also an award-winning contester and DXer. I’ve known Scott for years and knew he’d not only be a great steward of the Par product line, but also push new innovations.

I emailed Scott asking if Vibroplex had a field-portable antenna that would be resonant on 40, 30, and 20 meters. Turns out, there’s a Par antenna designed specifically to pair with the MTR-3 series transceivers: the Par EndFedz EFT-MTR.

Scott pointed me to a description of the antenna on the Vibroplex website:

The new EndFedz ® EFT-MTR is a 40m/30m/20m tri-band QRP antenna rated up to 25 watts. The “MTR” name was selected as LNR Precision developed this antenna to be the perfect companion to the wildly popular 40/30/20m Mountain Topper QRP transceiver. The EFT-MTR’s total length is 65′ of 22 AWG polystealth wire and weighs less than 4 ounces! It is built with the same high level of workmanship and quality that you have come to expect with all EndFedz ® antennas.

A particular innovation on this antenna: This EndFedz is a little different than previous designs. The user has the option to remove an SMA connector at the end of the 30M resonator to enable just 30 meters, or keep the SMA installed for 40 and 20 meters. Because of the broad bandwidth of the antenna, it is unlikely that it will require tuning in the vast majority of deployments. This is particularly true of 30 meters where the band is very narrow. As our tagline states, “They Just Work!”

Included with the EFT-MTR is the EndFedz Antenna Winder. Conveniently allowing winding up the antenna line to not have a tangled mess at the end. The winder will hold both the antenna and 25 feet of RG-174U coaxial cable (optional accessory).

Scott offered to send me an EFT-MTR to evaluate in the field (disclaimer: at no cost to me) and I accepted without hesitation, of course!

An EFT-MTR field review

I’ve taken the EFT-MTR antenna to three park activations at this point and have formed some opinions about it.

The EFT-MTR fits perfectly in a slide-in pocket in the main compartment of the Boot Boss.

First of all, I couldn’t be more pleased with the size as it fits perfectly in my MTR-3B field kit built around my Red Oxx Booty Boss pack.

I really like the built-in antenna winder: it’s larger than that of the EFT Trail-Friendly, but also much easier to wind up and manage post-activation.

I’ll admit, the length of the EFT-MTR was a bit surprising the first time I deployed it: 65 feet.  Keep in mind, though, I had been used to a much shorter 41 foot radiator on the EFT Trail-friendly. Occasionally, I operate in spots where I simply don’t have the room to deploy a long antenna. I also worried that the EFT-MTR resonance might be negatively affected by winding its way through trees and over a branches. The MTR-3B transceiver does not like high SWR values and has no built-in SWR meter to monitor it. Last thing I wanted to do was harm the MTR finals.

You might be able to spot the feed point of the EFT-MTR at my activation of K-6952 this week.

Fortunately, winding its way through trees doesn’t seem to have a significant impact on SWR.

Each time I’ve taken the EFT-MTR to the field, I’ve also taken my KX2 which I’ve used to read the antenna’s SWR value. So far, the difference has only been negligible and SWR well within the tolerances of the MTR-3B.  Score!

I should note here that since I’ve started using an arborist throw line, I’m also able to hang antennas much higher than I could before. This has had a huge impact on all of my field activities.

Removing the SMA cap changes the EFT-MTR from a 40/20 to a 30 meter resonant antenna.

To be resonant on 40, 20 and 30 meters, the EFT-MTR requires a field modification. On the coil about 2/3 the way up the antenna, there’s an SMA connector with a small screw on cap (see above). When the cap is on (thus completing the connection) the antenna is resonant on 40 and 20 meters. You must remove the cap for it to be resonant on 30 meters.

Since I’ve been using the EFT-MTR, I start an activation on 40 meters (which is typically my most productive band), then move to 20 meters (typically, my least productive). If I have the time, or need the extra contacts to confirm a valid activation, I lower the antenna, unscrew the SMA cap, and raise the antenna again.

I thought at first this would be a major pain, but it hasn’t. Now that I’m using an arborist throw line, it’s super easy to lower and raise antennas. But even when I’ve used fishing line, it really hasn’t been an issue.

The only issue I see is I’m afraid I’m going to lose that little SMA cap in the field. To prevent this, I’ve made it a routine to immediately put it in the internal zippered compartment of the Booty Boss pack. I might find a source for those caps, though, just in case I still lose this one.

I’ve been very pleased with the EFT-MTR’s performance. I’m guessing it’s actually higher gain than my beloved EFT Trail-Friendly antenna. On my last activation with the EFT-MTR, I knocked out eight 40 meter contacts in about eight minutes during a period of poor propagation. Note that the MTR-3B was only pushing 3 or 4 watts of power.

I then moved to 20 meters where, frankly, propagation was so crappy I didn’t hang out there long. Instead, I lowered the antenna, removed the SMA cap, and started calling on 30 meters. Within a few minutes, I racked up the rest of my contacts.

I was very pleased with how quickly the Reverse Beacon Network picked up my CQs and was thus auto-spotted on the POTA website.

Conclusion?

If you own a Mountain Topper MTR-3 series transceiver, I highly recommend the EFT-MTR antenna. As with my EFT Trail-friendly and Par sloper, the quality is top-shelf. I expect the EFT-MTR will last even longer than the EFT Trail-friendly since the winder is so accommodating and the in-line coil is designed so that it doesn’t snag on branches as easily.

I’m looking forward to much more field fun with the MTR-3B and EFT-MTR combo!

Click here to check out the EFT-MTR at Vibroplex.

Click here to check out Vibroplex’s full line of antennas.

Many thanks again to Scott at Vibroplex for sending me the EFT-MTR for evaluation!

LnR Precision’s new Sideswiper produced for the Straight Key Century Club

Those of you who are fans of single lever paddles will be pleased to learn that LnR Precision has announced the latest key in their product line: the SKCC Sideswiper.

Here’s the description from the product page:

The SKCC Sideswiper is patterned after the Kungsimport key produced in Kunsbacka, Sweden in the 1980’s by Hakan Scard (professional operator at Gothenburg Radio, SAG) and Ben Jomkert. It is a classic very traditional Sideswiper produced for the Straight Key Century Club.

The light weight Oak fingerpiece allows for a close gap setting making it a very fast key with little chance of chattering. The heavy 2.8 pound base makes it a very stable device on your desk. No chasing this key around the desk or needing two hands to operate.

Key Features:

  • The SKCC Sideswiper base has a 4″x 3.25″ powdercoated cold rolled steel base with SKCC logo
  • The blade is highcarbon spring steel and features a Lightweight Oak Fingerpiece
  • Upper hardware is anodized aluminum with matte finish.
  • Weight is 2.8 lbs

I think this is a beautiful key–I love the simple design, heavy base and the fact they’re made by a quality key manufacturer.

The price will be $94.95 US.
Thanks for the tip, WD8RIF!

Click here to learn more about the SKCC Sideswiper at LnR Precision.

The new LNR Precision LD-11 transceiver is essentially general coverage

[FYI: This is a re-post from my blog, the SWLing Post]

LNR-Precision-LD-11

A couple weeks ago, LNR Precision sent me their new LD-11 Digital Direct Conversion QRP transceiver on loan for review.

The LD-11 is basically a small, tabletop SDR transceiver. It’s like a miniature, simplified version of the Icom IC-7100 I’ve also been evaluating.

The LD-11 is an all-mode and all-band transceiver–meaning, it includes SSB, CW, CW-R, Digi, AM and FM modes on all amateur radio bands (160 – 10 meters).

Though the LD-11 isn’t advertised as having a general coverage receiver, it will indeed tune the entire HF band.

You do this by entering the LD-11’s administration mode. LNR describes this in the LD-11 product manual, but suggests you contact them for help the first time you do this. In the admin panel, you’ll find functions that allow you to set the band edges on each amateur radio band.

For a preliminary test of broadcast reception, I moved the lower band edge of the 30 meter ham radio band to 8.2 MHz.

LNR-Precision-LD-11-front panel

After saving the settings and re-starting the LD-11 in normal operation mode, I could then tune the entire 31 meter broadcast band on the LD-11.

Hypothetically, you could either widen each amateur radio band to include adjacent broadcast bands, or you could simply set one of the ham bands to include the entire HF spectrum. To make it easier to navigate and tune through the bands, I’m choosing the former method over the latter.

Since the LD-11 has a proper AM mode, broadcasts sound great–especially via headphones!

Proper AM filters for broadcast reception!

Better yet?  The AM filter width can be widened to an impressive 9.6 kHz! Woo hoo!

LNR-LD-11-Shortwave-AM

The LD-11 has four filter slots: F1, F2, F3 and F4.

The F1-F3 slots can be set to a fixed user-defined widths (common widths are default).

F4 can be altered to any available filter width without having to enter the admin mode of the transceiver. Simply press the “F” (blue function button) and the FILTER button simultaneously and use the encoder/tuning knob to specify the filter width in .1 kHz steps. Pressing the F and FILTER button simultaneously again, will save your filter width for the F4 position.

I’ve been using the F4 filter position for widths between about 8.2 and 9.6 kHz in AM.

It’s still early days with the LD-11, but I’m enjoying this little transceiver immensely. It reminds me of one of my favorite QRP transceivers of yesteryear: the Index Labs QRP Plus (though the LD-11 is much smaller, more versatile and has a much better front end than the QRP Plus!).

LNR Precision sold out all of their first run LD-11 units within moments of having announced availability. I’m willing to bet they’ll bring a few LD-11s to the upcoming Dayton Hamvention, though.

Check inventory status and view LD-11 details on LNR Precision’s website. 

LRN Precision announces two new QRP transceivers: the LD-11 and MTR5B

LNR-MountainTopper-LD11-Announcement

LNR Precision announced two new QRP transceivers this weekend: the MTR5B and LD-11.

Below, you can find details I pulled from LNR’s press release and website for both units:

LNR-Precision-LD-11

The LD-11

The LD-11 is a new 11-band QRP transceiver based on the LNR’s LD-5 transceiver. The LD-11 covers from the 6 meter band down to the 160 meter band. A new feature on this model is a built-in panadapter. AM/FM/SSB and CW modes are all included.

Here is the description from LNR’s website:

The new LD-11 is Digital Direct Conversion, SDR type, build-in CPU (SM32a) DSP radio in which RF signals are directly converted to a digital data via differential and balanced A/D converters. This enables direct sampling with extremely low phase and floor noise.

The DSP is unique and features two independent channels. It also employs a unique differential algorithm within the software which is applied for IQ processing of the channels with phase suppression of the unwanted side-band channel.

The balanced ADC and DAC gives additional noise floor reduction and the receiver can handle interfering signals that are 100 dB stronger than the desired signal at a frequency separation of 10 kHz, and is about 130 dB stronger at 50 kHz separation. As the receiver and transmitter are using the same DSP channel, there is no gap between the receiver performance and the transmitter performance. Thus, there is a clean neighborhood on the bands. At the development stage, our intentions were motivated by the TX side-band noise of existing SDR manufacturers, so our aim was to fully equalize our transmitter to have noise performance that is compatible with the best modern receivers, or even better. After a arduous year of development , we think we achieved it!

This 11+ band radio is based on the LD-5, which has proven to be one of the most exciting QRP transceivers introduced in the last few years. Quite frankly, the performance rivals high end units offered by other manufactures at a much lower price point. Our motto is that we make QRP transceivers that you will want to take out in the field (without fear of breaking the bank).

LNR-Precision-LD-11-L-Side LNR-Precision-LD-11-R-Side

Note: I will review the LD-11 in the coming weeks and post images and notes here on QRPer.com.

MTR5B

The MTR5B

The new MTR5B 5-Band Mountain Topper is a fully-assembled 5-band CW transceiver KD1JV designs “Steve Weber” kit. The following are specifications/features from the LNR website:

40M, 30M, 20M, 17M, 15M
Size: 4.337″L x 3.153″W x 1.008″T
Weight: approx 6.4 OZ.

Features:

  • Switch selected 40/30/20/17/15 meter bands (no band modules to lose or change out)
  • Wide operating voltage range, 6 to 12 volts 15 ma Rx current at 12V supply
  • Efficient transmitter. Low current with 4W output
  • LCD display
  • Push button or Optional rotary tuning
  • 24 hour clock built in, with battery back up
  • Three 63 character programmable message memories
  • Message beacon mode with adjustable pause time

MTR5B-1

If you were lucky enough to grab a first production unit of either of these radios, I would love to post your overview/review! I’m looking forward to checking out the LD-11.

Mountain Topper Radio review by G0POT

MountainTopperRadio-MTR-Via-LNR-Precision

(Source: Southgate ARC)

Michael Sansom G0POT has released a video review of the LNR Precision version of the MTR, Mountain Topper Radio, a three band, CW only, QRP trail friendly transceiver

Watch Michael’s Mountain Topper Radio review below:

G0POT https://twitter.com/DrOrthogonal

Fully-assembled Mountain Topper rigs soon available from LnR

MountainTopperMany thanks to Chris (K4RCH) for passing along this message from Steve (KD1JV) at LnR Precision:

I am pleased to announce that the 3 band Mountain Topper will be commercially available as a fully assembled product from LnR Precision. They should be available for purchuse around the end of January and will cost $250.00

Steve KD1JV

If you’d like a peek at The Mountain Topper manual, click here to download (PDF).

Steve (KD1JV) is well-known for his brilliant QRP transceivers–$250 is a true bargain. Check out AE5X’s blog for more info about the MTR.