Tag Archives: Off-Grid radio

Winter radio life and preparing for power outages

Listening to a local station with the BC-348-Q until we lose power.

Here at SWLing Post HQ we’ve been under a Winter Storm Warning since yesterday–it’s not set to expire until sometime tomorrow. This storm hasn’t been all snow–it’s a mixture of snow and ice. If this continues, I fully expect to lose power at some point today.

In general, we’re prepared to handle this sort of thing: our refrigerator and freezer are powered by solar and completely off-grid, we have a super efficient RAIS woodstove to keep us warm and of course, we have a generator at the ready if needed.

Playing radio off-grid

As I write this post, I’m listening to the Signal Corps BC-348-Q (photo above) which is tuned to a local AM broadcaster. It’ll fill my shack with local news/tunes and its vintage valves will do a fine job warming this small room until the power eventually goes out.

When it does go out, I’ll switch to my blackout buddy, the CommRadio CR-1A.

I find that the CR-1A is nearly ideal for off-grid and field listening, as long as you have a good external antenna. The internal Li-Ion battery powers the thing for ages and it has an incredibly capable receiver.

Of course, I also have an Elecraft KX3 and KX2 which can be powered by battery, but I tend to use the CR-1A for broadcast listening and save the KX2/KX3 for off-grid ham radio QRP fun.

In addition, I have the new battery-powered CommRadio CTX-10 transceiver in the shack.

I’ve been receiving numerous emails about this particular field rig because there are so few CTX-10 reviews out there even though it’s been on the market since late July.

Please note that I’ve been giving the CTX-10 a thorough evaluation over the past few weeks and plan to publish my initial review in the next few days.

Bye-bye noise!

Even though I live in a very rural and remote area with little-to-no RFI, when the power is cut, my noise floor still drops . We’re not immune–like most homes, we have power supplies and devices that emit radio interference.

It’s funny: most urban radio enthusiasts I know don’t fear power outages, they prepare for and embrace them! When all of those RFI-spewing devices go silent, it’s simply amazing what you can hear from home on frequencies below 30 MHz with pretty much any receiver.

Personally, as long as I have a means of 1.) powering my radios, and 2.) making coffee (extremely important), I consider myself properly prepared.

I’ve always got those two points covered.

Bring it, old man winter!  I’m ready to play radio!

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Steve searches for a USB-powered battery charger for solar recharging

Many thanks to SWLing Post contributor, Steven Crawford, who writes with the following inquiry:

[I’m searching for] good quality USB powered battery chargers for AA and D size rechargeable batteries.

Wall outlet chargers are common but quality USB powered battery chargers appear much less common…less common than the packable solar panels with USB ports such as Anker’s, that could be used to power them. Ideally the charger should handle Nicad’s, NIMH and Ii-on but have standardized on AA, AA + D adapter sleeves, and D batteries for my storm supplies.

If I understand correctly, you’re searching for a good qualityUSB-powered battery charger that supports multiple battery chemistries (nickel-cadmium, NIMH and lithium ion) so you can recharge AA, AAA and D batteries with a portable solar panel.

I’m hoping SWLing Post readers can offer some suggestions.

I’ve also looked into this type of charger for both Ears To Our World and my own personal use when off-grid in the summer. I’ve never found one that truly supports all of the battery chemistries you mentioned. The one I’ve used (an EBL) works quite well, but only supports NiMH AA and AAA batteries. As you mentioned, you can use D cell sleeves with the AAs.

EBL makes a number of USB chargers that can be found by searching Amazon. This one–an EBL Quick Charger (affiliate link)–can recharge NiMH batteries within 40 minutes and I’ve personally used one. I’ve been pleased with EBL batteries as well.

I never use nickel cadmium rechargeable batteries at this point, so really don’t know what’s available on the market.

I have found that there are a number of USB-powered lithium battery chargers, but typically for specific lithium cell configurations like 18650, 16340, 14500, 26650, etc. Some of these inexpensive chargers have magnetic contacts that can fit almost any battery type and on Amazon and eBay they claim to recharge multiple battery chemistries, but frankly I’m quite skeptical. These $9 devices don’t seem to have a way of detecting battery chemistry, thus I’m not sure how they would adjust the charging cycle accordingly. Perhaps I’m incorrect in this assumption?

Other than using Powerfilm solar NiMH battery chargers (I can recommend these) which are incorporated in their folding panels, I’ve never charged batteries directly from a solar panel. Typically I have a 9ah or larger 12V battery floating between the PV panel and the charger.

I’ve found that using a 12VDC charger–like this–that’s pulling power from a 12V battery is simply a little more efficient, faster and reliable than charging directly from a small PV panel. Since I always have 12V batteries on hand when off grid, it’s a simple solution for for my system.

Post readers: do you have any USB-powered battery charging suggestions for Steven? Please comment!

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Off-grid/RV enthusiasts need a radio-quiet solar charge controller: reader advice?

The Solar Boost 3000i solar MPPT charge controller

I’m currently in the process of adding 200-300 watts of 12-volt solar panels to my truck camper.

Solar panels will keep my camper’s 12V deep-cycle battery topped off, thus allowing longer stretches of time for boon-docking or primitive camping, during which an occupied camper is off-grid from shore power.

My truck camper actually came with a simple built-in charge controller which charges the battery via shore power. Thing is…this shore power charger is incredibly noisy when I’m on the radio.  The QRM it generates is broadband, and almost entirely wipes out HF and MW radio listening.

Because of this, I’m forced to unplug my power whenever I’m in the camper and want to hop on the air. And since the whole idea of camper living is to enjoy a bit of rest-and-relaxation, in other words, to pursue one’s hobbies in modest comfort, having to unplug the power––or else not play radio––limits my total enjoyment of RV camping.

But. Before I invest in a new solar charge controller, which would essentially charge the battery any time the sun is out, I need to be absolutely certain it doesn’t create RFI, too. Yet I’m finding it difficult to confirm whether a charge controller is RF-quiet prior to purchasing…

What’s more, I suspect I’m not the only radio listener or ham radio operator with an RV who has encountered the noise dilemma.

What’s a radio geek with an RV to do––?

A ham radio buddy who is an avid RVer recommended the Solar Boost 3000i (see top photo above). While it might be overkill for my application, I’m willing to invest, knowing it may charge without creating RFI.

But before I do, I’m curious if any SWLing Post readers have any experience with solar charge controllers, and/or can confirm models that create little to no RFI? I’d even appreciate knowing which models do pollute the spectrum––models to avoid, in other words, if radio listening or ham radio operations are your goal.

My hope is that SWLing Post reader recommendations may not only help me with this problem, but might help other RVer/off-grid radio enthusiasts, as well.

Please comment!

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Off-Grid Radio: Portable power recommendations?

Elecraft-KX3This year, I have a lot of portable radio play in mind as I travel across the continent. At some point, I even plan to spend several days in an off-grid cabin on the coast.

In the past, I’ve powered my 12 VDC ham radio transceivers with a system comprised of three PowerFilm solar 5 watt foldable PV panels (see below), a Micro M+ charge controller and several gel cell type sealed batteries (a couple 7 Ah and one 20 Ah).Powerfilm-Solar-Panel

The system works well, but the batteries are a little heavy and unhandy when I want to hike into a remote site or play radio on the beach, for example.


In terms of receivers, my portables (like the Sony ICF-SW7600GR, Tecsun PL-660, etc.) simply use AA batteries which I charge with PowerFilm AA PV chargers (see above). My CommRadio CR-1a has an internal battery that will power it for hours at a time.

Power is much less of an issue with receivers because they’re quite resource efficient.

I mainly need a system to power my QRP ham radio gear, and that’s where I could use your experience!

Wish list

Charge controller

I need a new charge controller since my Micro M+ (no longer produced) is now being used to power a remote antenna tuner.

Of course, I’ll need an inexpensive charge controller that doesn’t produce RFI (radio interference).

It would be an added bonus if the charge controller could also charge my batteries when grid power is available.

12 VDC Battery packs

I’d like something relatively lightweight and safe.

Note: LiPo packs worry me, especially since I had one (an early GoalZero model) quite literally melt down and burn up on my bed only a few hours after bringing it back from an eight hour flight a few years ago. Scary!

Pure Sine Wave Inverter


I’d also like a small, efficient pure sine wave inverter that I I could connect to my largest battery and power my laptop for extended SDR spectrum recording sessions while off-grid.

I’d love a recommendation from someone who uses one and can confirm a model that doesn’t create radio interference while operating.


Post readers: Please comment with your recommendations and include model numbers and links if possible. Thank you in advance!

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CommRadio CR-1 and WRTH: Power outage essentials

Like much of North America, we’re currently experiencing record low temperatures and strong winds here at our mountain home. This morning, I woke to no power and no Internet. My iPhone still works though, hence the ability to publish this post.

But no power is really no problem when it comes to SWLing. Indeed, for those living in urban areas, power outages represent temporary refuge from all of those electronic noises (RFI) that plague daily listening.

I’ve spent the morning SWLing with my CommRadio CR-1. The beauty of the CR-1 is that it can operate for hours on its internal battery and can also be charged/powered via USB or anything from a 6V to 18v DC power source. I’m currently charging the CR-1’s battery from our solar-powered battery bank. It makes me realize that the CR-1 is an ideal, top-shelf radio for off-grid DXing.

Additionally, I received my 2014 WRTH yesterday in the post. The WRTH is always a welcome delivery, but this morning was even more appreciated since it requires no power source whatsoever to work!

No power? No worries! With a WRTH and CommRadio CR-1 combo, I’m a happy listener!

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Living off-grid? The ideal shortwave radio system for you

While the Tecsun GR-168 is my current pick amongst self-powered shortwave radios, their performance is only mediocre compared to a proper, hobby-grade receiver with SSB.

While the Tecsun GR-168 is my current pick amongst self-powered shortwave radios, performance is only mediocre compared with a proper, hobby-grade receiver with SSB.

What’s the best system for off-grid living? From time to time, I’m asked this question in the “comments” section of the website or via email.  Recently it came up again, and I thought it might make sense to answer it here, and also open it for discussion.

Specifically, SWLing Post reader, Phil, writes:

“[H]i, I am looking for a SW radio that can be used in an off-grid location (rechargeable/ wind-up/ 12 volt DC/ or solar powered), that can pick up a wide range of English speaking stations from here in SW Spain, fantastic audio quality, in the £100-200 price range, and can pick up ham etc transmissions in an emergency (with SSB?).  I know NOTHING about SW, so the CCRadio-SW looked about right, except it doesn’t have SSB.  Any other suggestions?


Our little solar cottage, where The SWLing Post is often produced from the sun’s energy

Phil, I’m glad you asked. I may be uniquely qualified to answer this question, as I live in and work from a solar house that is off-grid at least some of the time, and I run a charitable non-profit, Ears To Our World (ETOW), that uses shortwave radio for educational purposes.  ETOW works in schools, homes, and entire communities that are very often extremely remote, and, by default, off-grid.

So, you have a number of great options to choose from–and whatever options I overlook, our fellow SWLing Post readers will surely supply.

As the ability to receive SSB signals is important to you (and I agree), all of these options will take this requirement into account. You’ll notice that I’m not elaborating on crank/wind-up radios; while there are many of these on the market, none include SSB as an option. Fewer and fewer even include shortwave radio as an option. With that said, my current pick is the Tecsun GR-168 (photo above). Another to consider is the EU/Asian version of the Eton Rover (US versions lack SW, but feature NOAA frequencies).

Following are the options I would suggest for you–or for anyone looking to add a solar-powered radio system to their off-grid set-up.

The Tecsun PL-660

The Tecsun PL-660

Option 1: Portable radio

Most of the good portable radios on the market use AA batteries and can run quite a long time on a set.  I would recommend purchasing the Tecsun PL-660, Sangean ATS-909X, or the Sony ICF-SW7600GR. The PL-660 is possibly the best choice for ease of use and overall value; it’s an impressive little radio, and has good audio fidelity for the size.

Since these radios operate from AA batteries, I would simply purchase a 12V AA battery charger, if you have 12 volts DC available.

A PowerFilm Solar AA charger unfolded and charging on left, folded panel on right.

A PowerFilm Solar AA charger unfolded and charging on left, folded panel on right.

The other option would be to purchase a solar AA battery charger. I’ve tested a lot of these, and the best I’ve found are made by PowerFilm Solar here in the USA. What I like about these solar chargers is that they can charge either two or four batteries at a time––the panel folds out and has enough wattage to charge depleted cells within a few hours of sunlight exposure.  Folded up, they’re small enough (a little larger than a wallet) to be used for travel.

I have used PowerFilm’s solar chargers extensively and they continue to impress.  Note, however, that they are not waterproof––you cannot leave them outside in rainy conditions.

This radio/panel combo can be purchased for under $250 US (£155/185 EUR).

Option 2: Tabletop receiver

The CommRadio CR-1

The CommRadio CR-1

If you have access to 12 volts DC in your home or cabin, and you’re less concerned about portability, then a tabletop receiver might fit your price range and will offer you better performance, when coupled with a reasonable outdoor wire antenna.

You would want to find a tabletop receiver that could run on 12-13.8 volts DC. Many amateur radio-class communications receivers will do this. I would recommend one of the following:

  • The Alinco DX-R8: an excellent receiver for the price. You can find them used for around $350 US. I ran one off solar power here at my home for almost 2 years.
  • The CommRadio CR-1: A new product this year. A bit out of your £100-200 price range, Phil, but worth considering as not only is it beautifully engineered, but it’s portable, and operates anywhere from 6 to 18 VDC! As a bonus, it has a built-in battery that will power it for hours.  I’m due to publish the full review of the CR-1 very soon–here’s a quickie.

The Alinco DX-R8T tabletop shortwave receiver

One side note: It’s possible–depending on the type you use–that your home’s solar charge controller(s) could inject a lot of noise into your daytime shortwave radio listening.  My charge controller does this, but I can turn it off and, if it becomes too much of a problem, actually modify it to do charging with less switching.

The Elecraft KX3 general coverage Transceiver (Click to enlarge)

The Elecraft KX3 general coverage Transceiver (Click to enlarge)

Option 3: Get your amateur radio ticket and a transceiver

This option is identical to option 2, other than instead of buying a receiver, you buy a transceiver. I’m talking about becoming a licensed amateur radio operator or “ham.” Living where you do, and being a bit of a preparation guru, I can assure you that a ham radio license is a true asset and can keep you connected with the world when everything else fails or when you want to chat with a friend 3,000 miles away.

It’s well beyond the scope of my advice here to cover amateur radio–it’s a vast and multi-faceted hobby–but as a ham (callsign K4SWL–and, formerly, M0CYI in the UK) I can tell you that becoming one is a decision you’re not likely to regret.

A brochure of the original IC-735. These can be easily found for $300-350 US used.

A brochure of the original IC-735. These can be easily found used for $300-350 US (220-260 EUR).

If you’re licensed, you can purchase a general coverage ham radio transceiver and not only be able to use the rig for ham radio purposes, but also for all aspects of shortwave radio listening. I spent many years using the (now very affordable) Icom IC-735 as my shortwave receiver. Though I have dedicated receivers at home, I now use the Elecraft KX3 for ham radio and receiving on the go.  I recently posted a review of the KX3 that can better explain in detail.

Phil, since you’re from the UK, consider contacting the RSGB and asking about becoming a ham in Spain (or getting licensed in the UK and getting a Spanish call sign). If you lived in the US, I’d advise you contact the ARRL, or in Canada the RAC.  Most countries, however, have a support organization for amateur radio–the IARU can help guide you.

More options?

I’m sure SWLing Post readers may also have suggestions for off-grid SWLing–please check this post’s comments.

Readers: be sure to check out Phil’s website about simple, off-grid living in southern Spain.  Phil, thanks for the question!

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