Category Archives: Portable Radio

The Tecsun PL-880: triple conversion architecture

Many thanks to SWLing Post contributor, Larry Thompson, who writes:

There’s been some confusion on my part whether the Tecsun PL-880 is a dual conversion or triple conversion receiver. Amazon and eBay list the receiver as double conversion, whereas Universal Radio doesn’t mention either.

After scouring the Instruction Manual, I was pleased to learn that the PL-880 uses the Silicon Labs si4735 DSP microchip and has 4 Intermediate Frequencies.

1st IF: 55.845 MHz
2nd IF: 10.7 MHz
3rd IF: 45 kHz
4th IF: 128 kHz (exclusively for FM)

To me, that looks like a triple conversion architecture. The combination of the DSP microchip, and the triple conversion would explain why my Tecsun PL-880 is so much more sensitive and selective than my Sony ICF-SW8600GR.

My CountyCom GP-5/SSB emergency portable also has the same Silicon Labs DSP chip and it is almost as sensitive as the Tecsun PL-880, far more sensitive than the Sony. I’ve owned a Japan Radio JRC-525 and a Yaesu FT-900AT transceiver for many years, and the PL-880 digs out weak signals better than both those tabletop receivers, both dual conversion.

To quell the speculation, yesterday I contacted Anna at Anon-Co, the worldwide distributor for Tecsun radios. Her quick reply confirms my suspicions that the Tecsun PL-880 is indeed a triple conversion receiver. That would explain why it blows my Sony ICF-SW7600GR out of the water in senitivity and its ability to pull out weak stations.

Among all the other great attributes, this is an welcome discovery and one never mentioned in the specs by the various retailers of this receiver!

Thank you Larry, for shedding light on this–Anna would certainly know.

Your note makes me realize that I really should order a second, current production model PL-880. My PL-880 is from one of the first batches produced. I imagine I could benefit from some of the firmware tweaks that have been made to this receiver over time.  Perhaps it would even be a good time to compare the 1st generation with the current generation?

I just checked and Anon-Co is selling the PL-880 on eBay for $153.99 US shipped.

Have any SWing Post readers compared early and late model PL-880 units? Please comment.

A very clever radio go-box using the Gator GR6S shallow rack case

(Source: Southgate ARC)

Young radio amateurs Zechariah WX4TVJFaith Hannah AE4FHHope KM4IPF and Grace KM4TXT have released a video about their Go Box

Many people have asked us to make a detailed video about our Go Box, so we decided to make one. We show you what is in the Go Box and how we installed all of the equipment. There is also some funny stuff in the video, too!

The case we used was a Gator 6 rack unit shallow case:
https://www.bhphotovideo.com/c/product/252763-REG/Gator_Cases_GR_6S_GR6S_Shallow_Rack_Case.html

The shelves are simply vented rack mount shelves. Here is a link to where you can get them:
https://www.sweetwater.com/store/detail/RkShelfU1

Watch A Close Look at Our Ham Radio Go Box and How We Put it Together:

Click here to view on YouTube.

Lea Family
http://hamradio.world/

These girls do an amazing job with the video–bravo!

I love this setup. While I typically pack very lightly for portable radio work, building a system like this makes for very quick deployment when you require a full 100 watt system with multiple radios and multiple accessories. Radio clubs could easily put systems like this together for events like Field Day or Emergency Comms. It’s grab-and-go at its best!

Of course, a field DXpedition/SWLing station could also be easily built into this portable system. In fact, I bet an SDR with computer, keyboard, and monitor could be mounted and accommodated in this space.

The Digitech AR-1780: a new SSB shortwave portable

Many thanks to SWLing Post contributor, Cap Tux, who writes:

This radio seems to have recently been released in Oz, no idea of its performance on SSB et al. but seems to do everything the C.Crane Skywave does. Heavy on batteries though at 4 x AA and nearly twice as heavy with similar dimensions to the Skywave, not major if it performs well and has good battery life.

Apparently the AR-1780 uses the SiLabs DSP chipset going by comments on Radio Reference. Also has RDS, Temp, the keypad layout looks similar to a Eton G3.

Taken from Jaycar’s website site:

This is a very compact world band radio, covering the most popular frequencies. It features rapid digital tuning, 1000 memory presets, and an easy to read display. Single Sideband Modulation (SSB) is used to listen in on 27MHz CB radio, short wave amateur radio and morse code. The large internal speaker provides clear audio, and you can connect your favourite set of headphones for personal listening. Powerful enough to receive what you want, and compact enough to take wherever you want.

Features:
– FM/MW/SW/LW/AIR Bands
– Single Side Band (SSB)
– Telescopic Antenna
– 3.5mm socket for external antenna
– Selectable Bandwidth: 1 – 6kHz

Specifications:
Radio Bands:
FM 87.5 – 108MHz
MW 522 – 1620kHz / 520 – 1710 kHz
SW 1711 – 29,999kHz
LW 150 – 450kHz
AIR 118 – 137kHz
Batteries: 4 x AA (not included)
Weight: 253g (Excluding Batteries)
Dimensions: 150(W) x 95(H) x 30(D)mm

Many thanks for the tip, Cap!

This looks like a full-featured portable. As mentioned, it certainly resembles the Grundig G3 in many respects.

If the AR-1780 performs well, it’ll be a very welcome addition to the Australia and New Zealand markets.

Please contact me if you’ve purchased the AR-1780 and would like to write a guest post/review. I’m very curious how well this portable stacks up against other portables especially in terms of overall sensitivity/selectivity and noise floor.

Portable Powerhouses: Comparing the Bonito Boni Whip and Wellbrook ALA1530LNP Antennas

One fits in a car (well, most vehicles anyway) and another easily slides into a small daypack; which antenna is best for DXing on-the-go? The ALA1530LNP and Boni Whip are at opposite ends of the portability scale (as well as the price scale).

I’ve written about the ALA1530LNP in the pages of the SWLing Post before, where I compared it against another Wellbrook loop antenna on extremely weak medium wave signals. The ALA1530LNP currently costs $413 USD including shipping to the Seattle USA area where I live.

More recently I’ve been intrigued by UK Oxford Shortwave Log’s (YouTube) excellent videos demonstrating the DXing prowess of the very compact, highly portable Bonito Boni Whip antenna. Through a Bonito USA dealer I was able to purchase the Boni Whip at an attractive $99 USD price (plus $11 shipping).

So, is it fair to compare “apples and oranges”? Maybe not, but it was fun and interesting nonetheless to take both antennas to the countryside to find out how they perform head-to-head in a portable situation. My destination was a small forested campground, in a valley east of this beautiful Mount Rainier, Washington scene:

In mid-July, Tipsoo Lake near Mt. Rainier is still surrounded by snow.

Over the course of three days I compared the two antennas with these receivers:

  • Eton E1XM
  • Sangean ATS-909X
  • Elad FDM-S2

I set up the E1XM and ATS-909X receivers on a portable tote box with the antennas powered by SLA gel cell batteries and using a two-way antenna switch for instant comparisons.

Each antenna was mounted on its own “pro” speaker stand and separated 60 feet from each other. The antennas were connected to receivers by equal 100 foot lengths of RG-58 coax cable, and were over 80 feet away from my laptop computer (the only noise source in the area).

In keeping with the uber-portable theme of the Bonito antenna, I used a very compact 1.2Ah SLA gel cell battery for its power injector (junction box). Since the antenna consumes a mere 45 ma. of current, this small rechargeable battery will power the Boni Whip for many, many hours.

The Wellbrook ALA1530LNP requires a still reasonable 200 ma., and I brought along a much larger battery to power it.

Below are a selection of 30-second medium wave and shortwave recordings, each one of them beginning with the Boni Whip and switching to the ALA1530LNP midway through the recording.

Boni Whip vs ALA1530LNP – E1XM Receiver

660 kHz

870 kHz

1660 kHz

3330 kHz, CHU Canada

4960 kHz, VOA Sao Tome

9535 kHz, R. Algerienne

11600 kHz, Denge Kurdistan

11760 kHz, R. Havana Cuba

EDIT 7/14/2017: 11905 kHz, Reach Beyond Radio, Kununurra WA Australia (tentative; listen for the Aussie-accented weather forecast at the end of the Wellbrook loop portion. This catch was at 03:48 UTC, which matches up with the brief English language broadcast in Reach Beyond’s schedule for 11905 kHz. This catch does not appear to be China National Radio as  I first thought.)

Boni Whip vs ALA1530LNP – Elad FDM-S2

These 30-second videos are from the Elad SDR’s FDM-SW2 software. As above, the first half of each recording is the Bonito antenna followed by the Wellbrook loop. If you maximize the playback of a video to full screen you can read the signal-to-noise ratio (SNR) change (“Delta”) as the antenna is switched to the ALA1530LNP.

The compact Boni Whip is a unique commercial design of “mini whip” antenna, pioneered by Roelof Bakker, PA0RDT some years ago. As with all these compact e-field antennas they can be a significant “noise sponge”, collecting any RFI or interference in the area. This is especially true if the coax shield is not grounded. Despite using two Bryant/Bowers design of RF chokes in series, the Boni Whip’s reception was degraded by RFI emitted from my laptop over 80 feet from the antennas. The RFI was quite a bit worse without any RF chokes in-line. You’ll note though that even the Wellbrook loop received some interference from the laptop on the higher shortwave frequencies.

4840 kHz, WWCR, Nashville TN USA

5985 kHz, R. Taiwan Intl. via WYFR, FL USA

6090 kHz, The Caribbean Beacon, Anguilla (distorted, with transmitter problems)

6100 kHz, R. Havana Cuba

9600 kHz, unidentified station

11725 kHz, R. New Zealand Intl.

11790 kHz, R. France Intl., Issoudun

11840 kHz, R. Havana Cuba (target: Chile)

Observations. On medium wave (E1XM examples) the directionality of the Wellbrook loop could be noted on one, maybe two of the three recordings. This can be a benefit–or not–depending on your goal. (I did not rotate the Wellbrook loop to null or peak any specific MW signals.) The omni-directional Boni Whip would not be the antenna of choice for a hard-core medium wave DXer; however, it is extremely compact and lightweight for camping and travel if you will be DXing or SWLing on shortwave also. The Wellbrook though is highly regarded as a medium wave DX antenna, especially when used with a rotor to take advantage of its sharp broadside nulls.

I didn’t test the Boni Whip on long wave, but Oxford Shortwave Log and others report it does very well on LF. I tried the antenna on FM frequencies against the Eton and Sangean’s telescopic whip antennas but in every case the reception was worse on the Boni Whip.

As I expected on shortwave, the ALA1530LNP greatly outperformed the Boni Whip on some signals. On others, reception was extremely comparable! The 3330 kHz CHU recording surprised me with the neck-and-neck reception. At this tropical band frequency there may have been some directionality to the signal, and the loop may not have been oriented optimally. The 4960 VOA reception was also very close.

I was disappointed, but not surprised at the RFI pickup of the Boni Whip when using my laptop and the Elad SDR receiver. The two RF chokes tamed the spikes and hash a bit, but removal was far from complete. The Wellbrook wasn’t always “clean” in this regard though.

Final notes. I think the Boni Whip is an extremely high value in a “jack of all trades” very portable antenna. Like Oxford Shortwave Log and others, I find this active antenna’s noise level to be extremely low, helping its sensitivity reveal weak DX signals in a surprising fashion. I would not hesitate to use this antenna away from noise sources when traveling with a non-computerized receiver. Well done, Bonito!

Is the Wellbrook ALA1530LNP worth four times the Boni Whip’s USA price? To the serious DXer who has no room for large passive antennas (Beverages, phased delta loops, DKAZ, etc.), the 1-meter diameter Wellbrook is clearly in a class of its own. By the way, the US Dollar to UK Pound ratio has improved in recent months, so the Wellbrook is an improved value for USA radio hobbyists now.

Truly this was an “apples to oranges” comparison, but I thoroughly enjoyed using both models. I welcome your comments, particularly if you also own both of these fine antennas.


Guy Atkins is a Sr. Graphic Designer for T-Mobile and lives near Seattle, Washington.  He’s a regular contributor to the SWLing Post.

Brilliant hard-core DX with the USB-powered Bonito MegActive MA305 antenna

 

Hi there, you might remember my post from last month focussing on the Bonito MegActive MA305 E-field antenna, kindly supplied to me for testing, by Bonito themselves. That post was essentially a report on my experiences travelling to Crete with the MA305, navigating through security at London Gatwick and Heraklion airports (mostly with relative ease), but more importantly, how well it worked with the equally excellent Eton Satellit portable receiver. Whilst in Crete I managed to copy a number of personal firsts, including CRI on 7295 kHz, via their relay in Bamako, Mali, The Voice of Beibu Radio on 5050 kHz, Nanning, XSL ‘Slot Machine’ on 6251 kHz USB, Ichihara, Japan, S32 ‘The Squeaky Wheel’ on 3828 kHz and NHK World Radio Japan, 11910 kHz. I also copied RTM Wai/Limbang FM on 11665 kHz from Kajang, Myanmar Radio on 5985 kHz and AIR Bhopal on 4810 kHz, amongst others – all of which I would certainly consider to be difficult catches in Europe.

 The USB-powered MegActive MA305 is perfect for DXing on the move…

Despite excellent all-round results from the ultra-portable USB powered MA305, there was one signal I copied, which more than any other, demonstrated the DXing credentials of this antenna; Radio Tarma from Peru on 4775 kHz. With a TX power of 1 kW, this is a very difficult station to hear in Western Europe, even with a longwire. To catch this station in Crete, with a 22 cm antenna was incredible and it was at that point during my trip that I realised E-field antennas really can work superbly well for hard-core DXers on the move.

Upon my return to Oxford, I immediately started thinking about a DXpedition to the local woods I use for what I consider serious DXing. For obvious reasons, E-field antennas require an electrically quiet environment to ensure maximum SNR performance. In noisy environments, these types of antennas amplify the signal of interest and the background ‘electro-smog’, thus increasing signal levels but critically, not signal-to-noise. Fortunately, the Oxfordshire wood I have been using for a couple of years is only a 10 minute drive from my QTH as I sort of live in the countryside anyway and the QRM levels there are just about zero. Now, given that this was essentially an experiment to determine the best possible performance from the MA305, I decided to use my best portable radio. It was quite tempting to pack up the Elad FDM DUO which running on a home-brew battery pack has proven itself to be my best (pseudo) portable radio. However, this is supposed to be a real-world test and in this type of scenario, DXpeditions with the Bonito antenna are much more likely to be undertaken with a portable radio. For these reasons I decided to conduct the test with the venerable Sony ICF-2001D. Having proven to be a superb receiver over many, many dxpeditions (check out the evidence on my YouTube Channel Oxford Shortwave Log) and still regarded by DXers as one of the best ever portable radios – possibly the best – it was the obvious choice.

 My portable DXing kit comprising the Bonito MegActive MA305 antenna and the Sony ICF-2001D…a bit of a legend in DXing circles…

I ventured out in early June around 23:00 hrs BST (22:00 hrs UTC), parked the car on the edge of the wood and proceeded to set up my cheap camera tripod, slightly modified to accept a 2 metre-long stainless steel tube, into which a slightly thinner 1 metre tube was mounted, topped off with my partially disassembled ‘Selfie Stick’ – which made it back from Crete lol. The antenna was set up in less than 5 minutes and approximately 4 metres above the ground – much quicker and easier than de-spooling 100 metres of wire! With fresh batteries in the Sony and the MA305 powered up using the USB power brick supplied by Bonito, I was ready to start listening. Almost immediately I heard and recorded a personal first; Lao National Radio, Laos, signing on 6130 kHz, with an excellent signal. Hearing them in the UK was only made possible by the annual two week shut down of the PBS Xizang transmitter in Lhasa, Tibet, but hey, I’ll take it. A brilliant start to my listening session.

Over the next two hours I was amazed at what could be heard using this 22 cm amplified antenna. Bearing in mind I have spent many hours at the woods previously, listening via various 100 metre longwires and a 200 metre Beverage, my expectations were, I thought, realistic in that the MA305 coupled to the Sony would catch some very good DX. However, I did believe there might be an absence of at least some of the more exotic low power stations on the Tropical Band – afterall the MA305 is a very short antenna. Clearly I was wrong, because what transpired during the session surpassed anything I thought possible with this set-up. A list of reception videos follows below and further below, a selection of embedded videos. Some of the entries on this list simply stunned me at the time. Rádio Educação Rural for starters is such an incredibly difficult signal to hear in Europe, even with a very large antenna. Thus, to hear them on an ultra-compact set-up felt very special. Radio Mali is another station that is very difficult to catch with any modulation, except on a large antenna and yet there they were – at the first time of trying. Similarly, Rádio Nacional de Angola and Alcaravan Radio are exotics that at best deliver very weak audio – and most of the time no audio. Furthermore, the signals from Emisoras Pio XIIMyanmar Radio and Rádio Clube do Pará were verging on what I would call superb…I’d never heard anything like it previously except via 100 (or more) metres of wire.

 The ICF-2001D and MegActive MA305              Rádio Educação Rural transmitter site in Tefé, Brazil

So what’s next? Well it would certainly be an interesting experiment to compare the performance of the MegActive antenna with the Wellbrook ALA1530 active loop in a similar environment. I have used the Wellbrook on DXpeditions several times, with often excellent results, however, it’s not designed to be portable and if SNR performance could be demonstrated as similar between these two products, given a very favourable price delta, the Bonito antenna would add up to be a very compelling purchase decision. More on that to come. In the meantime, thank you very much for reading/watching/listening and I wish you all excellent DX.

Please click on the links below for the reception videos on the Oxford Shortwave Log YouTube channel.


Selected embedded reception videos from the list above:

Clint Gouveia is the author of this post and a regular contributor to the SWLing Post. Clint actively publishes videos of his shortwave radio excursions on his YouTube channel: Oxford Shortwave Log. Clint is based in Oxfordshire, England.