A review of the LnR Precision LD-11 QRP transceiver

The following review was originally published in the October 2016 issue of The Spectrum Monitor magazine.


ld-11-npota-pk01Anyone who knows me knows that since I was licensed nearly twenty years ago, I’ve been a fan of low-power (QRP) operations. There’s just something inexplicably fun in being able to talk to the other side of the world using very low wattage. In a sense, I’ve always felt that, in the world of ham radio, QRP is truly the province of the magician.

It’s for this reason that I’ve owned, operated, reviewed, and beta-tested a number of QRP transceivers over the years. What I look for in a QRP transceiver is quite different than what I’d look for in, say, a base station or mobile transceiver. The glory of QRP gear is that it’s more portable than its “full gallon” cousins in the transceiver world, allowing for radio communications on the go. QRP rigs tend to be more compact, lighter in weight, easier on batteries, less expensive, and provide built-in features to support field operation–even winter glove operation.

Of course, however, there’s typically compromise in smaller packages; neither would I expect a modest QRP transceiver to perform like a full-size base station. But I do expect it to perform well enough to satisfy my needs in the field or the shack.

Introducing the LD-11

lnr-precision-ld-11-am-mode-voice-of-greece

LnR Precision, Inc., is a North Carolina-based company that specializes in antennas, straight-keys, and last but not least, QRP transceivers. The company has produced a number of innovative QRP transceivers over the years, and for many of these years, I’ve been admiring these from afar. But earlier this year when the company announced their latest QRP transceiver, the LD-11, I was especially intrigued.

What really caught my attention this time is that this little transceiver is based on the architecture of their popular LD-5–a five-band, stand-alone direct conversion transceiver. Yet the LD-11 is actually an upgrade on that model, in that it supports 160-10 meter operation with all modes (SSB, CW, CW-R, Digi, AM and FM). Curiosity got the best of me: I had to see this for myself. I contacted LnR Precision, who kindly loaned me a transceiver for review.

Overview

The left side sports the key and mic ports, headphone jack, a line in/out jack and a side tone adjustment.

The left side sports the key and mic ports, headphone jack, a line in/out jack and a side tone adjustment.

The first thing that catches your eye is the unusual color of the LD-11: it is red. Very red. Though opinions will surely vary, I rather dig the hot-rod red aluminum chassis of this little rig. The red faceplate makes the buttons quite visible as well as giving the radio a unique and vivid appearance.

The backlit LCD display, meanwhile, is crisp and easy to read. It’s large enough that all of the pertinent information (frequency, voltage, mode, filter selection, and tuning step) can be displayed at once. When in transmit, there’s a meter below the frequency that displays either a bar scale or numbers for SWR or Power; when in receive mode, it displays the “S” meter.

The LD-11’s buttons have a tactile, responsive, and smooth action. The tuning knob, while lacking a finger dimple, rotates easily with an appropriate amount of brake.

You'll find the DC port, PTT out, CAT port and Antenna input on the right side of the LD-11.

You’ll find the DC port, PTT out, CAT port and Antenna input on the right side of the LD-11.

LD-11 operation is really very simple. I was probably on the air for hours before I ever needed to reference the owner’s manual for functions. LnR has done a great job giving the LD-11 a logical menu layout and intuitive front panel functions.

The radio’s front panel allows you to do the following:

  • turn the radio on/off,
  • tune with the encoder,
  • adjust AF gain,
  • key lock the front panel,
  • toggle the panadapter display,
  • toggle pre-amp and attenuator,
  • change tuning steps,
  • change mode,
  • move between bands,
  • turn on noise blanker and noise reduction
  • operate RIT and set-up split,
  • toggle VFOs, and
  • enter menu functions.

The menu functions give you control of still more settings, such as AGC settings, CW configuration, mic/voice transmit configuration, notch filter settings, NB/NR settings, meter display, transmit power, backlight settings, squelch, digital gain, and AM/FM mode enable/disable, among others. So this little transceiver is feature-rich.

Moreover, most menu items can be changed while you’re transmitting. While on the air, for example, I regularly toggle the transmit meter display between power out and SWR while calling CQ. Very handy.

Again, operation is straightforward and simple, especially good because at time of publishing this review, the LD-11 owner’s manual is still quite basic (click here to download PDF version).

On the air

Unlike most of my review radios, which spend a great deal of time in the shack during the evaluation period, the LD-11 spent most of its time in the field–in several US states, as well as in a couple of Canadian provinces. I even used the LD-11 for two weeks in an off-grid cabin on Prince Edward Island, Canada.

The LD-11, QRP Ranger, and Z-11 auto-tuner at the Hopewell Culture Park NPOTA activation.

The LD-11, QRP Ranger, and Z-11 auto-tuner at the Hopewell Culture Park NPOTA activation.

My first outing with the LD-11 was at Hopewell Culture National Historical Park in Ohio. Buddy Eric (WD8RIF), his son Miles (KD8KNC), and I made four National Parks On The Air (NPOTA) activations en route to the 2016 Dayton Hamvention.

We had a tight schedule for our NPOTA activations, so I couldn’t spend a great deal of time setting up my equipment. So on that day, I paired the LD-11 with Eric’s Z-11 auto tuner and a homebrew 40-meter doublet suspended from a tree. I powered the LD-11 with my Hardened Power Systems QRP Ranger battery pack.

And this combo worked brilliantly. At Hopewell, for example, I made twelve contacts, in short order, running SSB with just 8-10 watts output, and received positive audio reports.

Also that day, I discovered how exceptionally easy it is to operate the LD-11 in the field. When packing in, I appreciated how lightweight and compact it is, and that fire-engine red chassis meant there was no way I’d overlook it or forget it on the ground.

The LD-11 has two fold-down feet to support it on the shack table or in the field.

The LD-11 has two fold-down feet to support it on the shack table or in the field.

Two missing features, however, might make the LD-11 even more portable: these are an internal battery pack and an internal ATU. Unfortunately, there are no options for these at present (LnR, take note).

The LD-11 feet fold neatly under the chassis.

The LD-11 feet fold neatly under the chassis.

The external ATU, meanwhile, adds several extra items to manage: the ATU unit, the power cord, and an extra patch cable. Sure, if you’re operating all day from one location, none of that really matters. But when you’re doing quick deployments, every bit of kit that doesn’t require packing and unpacking also saves time and potential frustration. But I cheerfully used the above combo the rest of the day, logging even more contacts.

The EFT Trail-Friendly Antenna

At the Dayton Hamvention, I decided that one way to avoid taking an ATU to the field was to use a multi-band resonant portable antenna. I was quite busy at the Hamvention and didn’t want to spend time building one, so I decided to take the quick route and simply buy one. I visited a few vendors in Hara Arena and was impressed with the selection of field-portable antennas available. In the end, I was taken by the compact and easy-to-deploy design of LnR Precision’s EFT Trail-Friendly antenna, and purchased one on the spot. As many potential LD-11 owners might purchase the same antenna, I decided it might help to review it, too.

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

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

I bought a version of the EFT antenna that is resonant on 40, 20, and 10 meters. I like that band combo for NPOTA and SOTA activations, because I like operating on both the 40 and 20 meter bands. What’s especially brilliant about the EFT end-fed design is that you only need to suspend one side of the antenna: simply launch a line over a tree branch, and hoist the business end of the antenna up, and, snap–you’re ready to go. When wound up for transport, it’s also lightweight and takes up very little space in a kit bag.

On the way home from the Hamvention, we activated the same four parks yet again. Eric and I tuned the EFT antenna before its initial use, and it was then ready to go.

Eliminating the need for an external tuner and adding the simple EFT antenna to the mix meant that I could set up and take down my entire station in a matter of minutes.

The only thing that took time at all was finding a tree branch to hoist the end of the antenna–usually not a problem, especially in our Eastern US parks. Moreover, the transceiver-plus-antenna team was quite effective: I easily logged all the contacts needed for all four sites in the one-hour time slots we allotted.

LD-11 Performance

The QRP Ranger (left) and LNR Precision LD-11 transceiver (right)

The QRP Ranger (left) and LNR Precision LD-11 transceiver (right)

In brief, I’ve been very pleased with the LD-11’s performance on the air.

The LD-11 receiver is both sensitive and selective. Though I didn’t have the chance to test it in the RF-dense environment of Field Day, it never overloaded in the areas where I’ve operated.

Through my headphones, the LD-11’s noise floor is impressively low and the receive audio is excellent. At first, I was a bit disappointed that the LD-11 doesn’t have an RF Gain control–something I frequently use to mitigate background noise–but fortunately the noise floor is low enough, and the DSP architecture seems adaptive enough, that I’ve never needed to reach for an RF gain control so far.

Nonetheless, LnR: I do hope you’ll consider making RF Gain a future firmware update!

Modes

The LD-11 is jam-packed with modes: USB, LSB, CW, CW-R, AM, and FM.

The LD-11 can also handle a host of digital modes, and there’s the choice of two models to connect to your PC: one LD-11 model with the Prolific USB Adapter Chipset ($739), and another model with the more-universal FTDI chipset ($789). It’s outside the scope of this review to test the LD-11 on digital modes, but note that I plan to do so in the coming months. The modes I’ve tested thus far are SSB, CW, and AM.

When I operated SSB, I found the default filters quite effective and the receive audio pleasant. On transmit, I received a number of positive reports on the LD-11’s audio. What’s more, through a menu option you can can adjust the transmit audio equalization (three defaults) to better match your voice.

On CW, the LD-11 was equally as pleasant. On-board filtering is quite effective and audio well-balanced.

On transmit, there is one negative worth noting for the CW operator: the LD-11 does not have full break-in QSK.

While this isn’t a problem for me, because I find hearing signals between the dits and dahs I send rather distracting, I know many CW ops that don’t like using a delay on transmit, preferring instead a full break-in. LnR notes that the LD-11’s “maximum switching delay is 12mS and digital delay is 47mS.” If you set the LD-11 for the quickest response time, you can hear between most characters, but the relay clicking can be distracting. For all of my CW operations, I set the response time to 500ms.

The first time the LD-11 was operated in CW it was with my buddy Mike Hansgen (K8RAT). Later, I asked this experienced operator how the LD-11 sounded on the other end? His reply:

“The LD-11 put out a sweet, musical note that was very pleasant and reminiscent of the note of a valve transmitter. The LD-11 sounded better than any silicon transceiver I had heard in a long time.”

Wow…high praise, indeed. For those who don’t know him, Hansgen has high standards, and doesn’t hand out such compliments readily.

AM mode (and general coverage)

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

LNR-LD-11-Shortwave-AM

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

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

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 prefer the former method.

Since the LD-11 has a proper AM mode, broadcasts sound great–especially via headphones! Better yet, the AM filter width can be widened to an impressive 9.6 kHz–! When listening to a blowtorch signal, audio fidelity is most impressive.

For example, here’s an audio sample of the LD-11 tuned to the Voice of Greece on 9420 kHz, with a filter width of 9.6 kHz:

Click here to listen to a comparison of the LD-11 and Elecraft KX2 on the 31 meter band.

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).

The F4 position 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, again simultaneously, will save your filter width for the F4 position.

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

A panadapter

One final unique feature of the LD-11 is a built-in, simple panadapter. By pressing the F (function) and VFO buttons simultaneously, it will engage the panadapter which lines the bottom of the display.

The panadapter display is found at the bottom of the LD-11's backlit display.

The panadapter display is found at the bottom of the LD-11’s backlit display.

To be clear, the panadapter is very basic–it doesn’t include frequency markers, it’s monochrome, and it’s not very tall (height/depth helps to discern weak signals along the spectrum). In fact, when I first turned it on, I truly doubted its utility.

Yet after having used the LD-11 for several months, I can say that one of the first steps I now take when putting the rig on the air is to engage the panadapter. Though it’s quite simple, I find it a useful tool for chasing signals on bands, whether SSB, CW, or even AM broadcasters. It’s also very responsive and fluid, which helps make up for the fact that it’s solid in color and rather flat.

For example, the weekend before finishing this review, I activated PK01 (the Blue Ridge Parkway) for NPOTA. When I switched to 20 meters, the noise floor was so low that, when I first started calling CQ, I assumed that either the band was dead or the antenna wasn’t working. One look at the panadapter, however, showed me that there were some strong SSB signals on either side of my frequency. So I didn’t tune around, but simply continued to call CQ, which soon rewarded me with excellent catches (more on that below).

Summary

Invariably, all radios have strengths and weaknesses; here is a list of these from the moment I put the LD-11 on the air:

Pros:

  • Lightweight, compact size
  • Excellent ergonomics and simple menu-driven functions
  • Built-in, simple panadapter
  • Low current drain on receiver (….ma)
  • General coverage receiver
  • Low noise floor
  • Variable filter bandwidths
  • Rugged hand mic
  • Most menu items can be changed while operating PTT or CW
  • Headphone amplifier drives larger headsets
  • Internal speaker (see con)
  • Excellent CW transmit audio reports
  • Good LnR Precision customer service

Cons:

  • No internal ATU option
  • No internal battery option
  • No RF gain control (see noise floor pro)
  • CW operation is not full break-in QSK, some relay noise
  • No voice or CW memory keyers
  • Very basic owner’s manual
  • Occasional audio “pops” when tuning rapidly through a band
  • Internal speaker audio is mediocre (see pro)

ld-11-qrp-ranger-npota-pk01

All in all, the LD-11 is a superb little transceiver. It sits in a market with some heavy-hitters like the venerable Yaesu FT-817ND, the Elecraft KX3, and the new Elecraft KX2 (which I reviewed in the November 2016 issue of The Spectrum Monitor Magazine).

While the LD-11 lacks some of the portability of those rigs (specifically, options for an internal battery and ATU–again, please take note, LnR), its performance-for-price-point is right, in my opinion.

If you take the LD-11 to the field with a resonant antenna, as I have, all you need is a power source to be on the air in moments. If you pair the LD-11 with a simple ATU like the Emtech ZM-2 or the even smaller Elecraft T1, you’ll be able to tune wires to your heart’s content, and you won’t need extra power cables.

Oh, yes…there’s one more thing I must mention about the LD-11: this rig has, for lack of a better word, a “fun” factor. It reminds me of one of my favorite QRP radios from days gone by, the Index Labs QRP Plus. The QRP Plus had many performance shortcomings and wasn’t nearly as full-featured, as lightweight, or as small as the LD-11, but it was a fun radio due to its dead-simple controls, nice display, prominent tuning knob, and good ergonomics generally, making it a breeze to operate.

The LD-11 feels like what the QRP Plus should have been: a fun rig that delivers serious performance.

The LD-11 is also easy to use, and that certainly contributes to its sense of fun. Operation has clearly been well thought through by the LnR developers. Only a few days before capping off this review, I took the LD-11 to the field for its 6th National Parks On The Air activation. With eight watts in SSB and a 20 meter vertical, I worked Rhode Island, Texas, Montana, Manitoba, California, and Slovenia from a picnic table on the Blue Ridge Parkway. And it was great fun, underscoring the reason I get such a kick out of HF and QRP in the first place.

Of course, that’s the magic and the mystery of radio. But tools like the LD-11 make it all the more accessible. LnR Precision, I must say: pretty good trick. From your proverbial hat, you’ve produced the handiest little QRP rig I’ve seen in years.

Click here to view the LD-11 on the LnR Precision website.

20 thoughts on “A review of the LnR Precision LD-11 QRP transceiver

  1. Tha Dood

    Has anyone tried this ‘lil rig in mobile operations? It would be neat to see how well it handles vehicle noises and power line noises while using various Hamsticks. Mounting could be interesting, but one could make a dashboard harness for it. One thing that’s attractive, very low power consumption. QSO while parked and not drain your battery, like my Icom IC-7000 will. That draws about 2A on just idle RX.

    Reply
    1. Thomas Post author

      Good question!

      I’ve never operated the LD-11 mobile, but might try to use it one day from the car battery while the car is running and see how it copes with noise.
      -Thomas

      Reply
  2. Edward

    It is amazing how much gets crammed in a little box. If they want to improve the ergonomics, All the side interconnections should be moved to the back and have the connectors mate with an acessory box on the bottom containing a trans-match, battery pack/charger. Some type of protective rollbar (aka Grundig handles) on the front. The connections exit from the sides of the acessory box. I perfer the antenna connections from the top and the grounding stud on the bottom. But I think the Microphone/PTT, key and headphone jack should be on the front panel.

    Has anyone come out with a folding chair/desk to put portable rigs on for field use. Seen so many rigs on the ground, on rocks, logs and whatever. It is bad for the back being stooped over for hours on end.

    Reply
    1. Cap

      Yes, great review and a great little radio.
      Top tip when portable, use a mag loop and you don’t need an ATU.
      Any lengthy operations demands a good li-po high capacity battery anyhoo…not a problem.

      Reply
  3. DanH

    Who cares? Another SWL website that caters to hams. I’m done with The SWLing Post. It is just another oniline lie that dismisses SWLs.

    Reply
    1. Thomas Post author

      Hi, Dan,

      I’m first and foremost an SWL, but I’m also a ham and love to do radio in the field. You’ll note that one of the reasons I love doing these reviews is to check out the general coverage receiver portion of the transceiver. With less and less tabletop receivers on the market, general coverage transceivers are becoming a viable option even if you never get your license.

      Sorry you feel this way, but, hey you’re free to do as you wish.

      Cheers,
      Thomas

      Reply
  4. Robert Gulley

    Well, I defy anyone to find a more positive site concerning SW listening – I have been on the net for years, surf hundreds of sites, and have never found one as informative and positive concerning shortwave radio. I for one appreciate hearing about radios of all types, and all types of capabilities.
    And yes, I contribute comments and articles to this site, and consider Thomas a good friend, but my comments here are purely about the content – it simple is the best SWLing site around in my book. And I think most readers would agree with me!

    Reply
    1. Mike

      Robert, I couldn’t have said it better.

      So much thanks to Thomas and all of the contributors on the SWLing Post. This is not only my favourite shortwave radio website, it’s my favourite website!

      My shortwave radio bread and butter!

      Oh yeah–that LD-11 looks the charm! Is it water proof at all?

      Mike from Brisbane

      Reply
      1. Thomas Post author

        Thank you. No, the LD-11 is not water-proof. It’s chassis is pretty tight, but the penetrations around the buttons wouldn’t stop water.

        Reply
        1. Edward

          If the switches an pots are sealed you could take it apart and conformal coat the PCBs and reassemble it (this may void the warranty). I did this with a small portable radio, the IF cans were sealed with wax. It would not work under water but as soon as the water was shaken off it would come to life. The biggest issue is the speaker. When the conformal coat saturates the speaker cone, it permanently changes the tone

          Reply
  5. Pingback: A review of the LnR Precision LD-11 QRP transceiver « ToneSquelch

  6. Pingback: A review of the Elecraft KX2 general coverage QRP transceiver | The SWLing Post

  7. Paul Courson

    How did this rig perform on AM transmit? If you were on 40meters, there is lots of activity around 7285. The LNR on AM is being compared to the Elecraft KX2 with its AM upgrade, but the KX2’s passband seems inadequate for AM.

    Reply
    1. Thomas Post author

      Hi, Paul,

      I’ve never transmitted in AM mode. I’ll have to try sometime and on a day with good propagation.

      Cheers,
      Thomas

      Reply

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