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The FCC approved today the adoption of a rulemaking allowing AM stations to transition to all-digital operation.
Hubbard Radio’s “The Gamut” 820 WWFD Frederick MD has been operating in all digital mode since July 16, 2018 in collaboration with HD Radio owner Xperi. The new rulemaking will allow AM stations to go all-digital and establish operating parameters for doing so.
The FCC today also is opening a comment period on the removal of the programming duplication rule adopted in 1992. The rule limits AM or FM stations from airing more than 25% of total hours in an average broadcast week of duplicative programming. The rule applies to commercial stations in the same service (AM or FM) with substantial contour overlap that are commonlyowned or subject to a time brokerage agreement.[…]
Amateur Radios from the Past: The Index Labs QRP++
The Index Labs QRP ++ was an intriguing little radio manufactured back in the mid-‘90’s by Index Labs of Gig Harbor, WA. For those interested in QRP (low power operating, generally less than five watts output) this transceiver filled the bill perfectly. It supports CW and SSB, transmits on all WARC bands, covers 1.8 – 30 MHz receive, has full break-in CW and a built-in iambic keyer. It boasts 20 memories, weighs four pounds (perfect for portable operation) and measures 5.5 x 4 x 6 inches. It’ll run on a 12V 1.5 amp supply or a stout 12 volt gel cell. The internals (see second pic) are an engineering masterpiece with stacked circuit boards reminiscent of commercial rigs.
Index Labs QRP ++ on the test bench
I recently acquired one of these radios as I was heavily into QRP in the 1970’s while using a TenTec Argonaut 509 and vertical on our apartment house’s roof. Back then the sunspot numbers scored much higher than today and many contacts were made, most notably a CW contact with Japan with a paltry one watt. So for nostalgic reasons I had to have one of these QRP++ rigs even though more modern and sophisticated versions are available.
At the moment bench tested is being done prior to sending it into action. One important component needing replacement was the memory battery which was totally kaput. Interestingly, this battery not only keeps the 20 memories alive but also brought back to life the CB radio-style S-meter reminiscent of radios from decades ago. Other items on the testing “to do” list will be checking power output, frequency accuracy, drift, and finally, on-air performance. The radio will feed a ground mounted 31’ vertical with 53 radials. With the right ionospheric conditions hopefully contacts will be aplenty.
Neatly stacked circuit boards and clean layout of QRP++
Unfortunately, no service manual exists for this gem, but it rates a 4.1 out of 5 on the eham.net Richter scale, and a number of ops have published helpful information on problems, solutions and modifications. Notably the first run of these radios was later replaced with improved models boasting higher performance via a custom designed mixer, so knowing the serial number of your unit helps to determine if yours was an upgrade.
Rear panel control layout. Power is adjustable and tested at a hair under 5W.
Thank you, Mario, for sharing this article and many thanks to the DVRA for allowing us to re-post it.
I owned a QRP++ for a few years and absolutely loved it. At the time, it was one of the most portable full-featured transceivers on the market. Although it can struggle in RF dense environments like Field Day or other contests, for daily use it was very effective. I eventually sold mine to fund the purchase of the Elecraft KX1 and, later, KX3.
I always loved the simple front-panel ergonomics of the QRP+ and QRP++. It’s an incredibly easy rig to operate in the field. Plus…it has a bit of a “cute” factor, if you like radios shaped like cubes.
There is a dedicated email discussion group for Index Labs transceivers–currently, they’re on Yahoo Groups but may migrate to another platform by end of year.
The Autumn 2019 edition of the BBC Monitoring’s magazine Monitor is now available on the web
BBC Monitoring provides news and information from freely available media sources around the world. Our round-the-clock monitoring of TV, radio, press, internet and news agencies is provided to the BBC and a range of customers – commercial clients, including media organizations, foreign governments, NGOs and universities, and the UK government.
BBC Monitoring is funded by the licence fee and is part of the BBC World Service Group.
Many thanks to SWLing Post contributor, Paul Evans, who shares the following video and article via Hackaday:
There’s been a spate of apocalypse related articles over the last few weeks, but when I saw an AM radio made from a hand-wound coil and an oxidized British penny, I couldn’t help but be impressed. We’ve covered foxhole radios, stereotypical radios that are cobbled together from found parts during wartime.
This example uses a variable capacitor for tuning, but that’s technically optional. All that’s really needed is a coil and something to work as a diode. Surprisingly, copper oxide is a semiconductor, and the surface oxidation on a penny is enough to form a rudimentary diode.[…]
Thanks for sharing this, Paul. I absolutely love simple receivers like this one. In the past, I’ve built several crystal radios and had great success hearing local AM broadcasters. Indeed, the very first kit I ever built was a crystal radio, then later a foxhole style receiver.
Post readers: Have you ever built a radio similar to this one that uses an oxidized penny? Please comment!
After an EDXC vote, by organisation members and individual members, Bucharest in Romania has been chosen as the destination for the 2020 EDXC Conference. It will take place in September 2020, dates and details are at the planning stages.
The two other contenders put forward by EDXC members were Skopje and Ohrid in North Macedonia and Malta.
Looking back a couple of months to September 2019, a report on the EDXC Conference in Andorra is online at the British DX Club website [PDF]. Written by Alan Pennington of the British DX Club, it captures the great atmosphere that these conferences always engender: travel, sightseeing, radio station visits, DX talk, interesting presentations, and socialising.
This coming weekend Encore – Classical Music on Radio Tumbril will broadcasting on a third frequency again.
The folks at WWCR in Tennessee are transmitting the show for the second time at 01:00 UTC Sunday 24th (Saturday evening 23rd local in US) on 6115 kHz.
Encore – Classical Music this weekend is – of course – being broadcast as usual by Channel 292 (Europe) on 6070 kHz at 15:00 UTC Sunday 24th November.
And by WBCQ on 7490 kHz at 01:00 UTC Monday 25th November.
There is a repeat on 6070 kHz on Friday 29th November at 19:00 UTC.
Do let us know how well you can pick up Encore at your location by emailing to [email protected]. We try to reply to all emails and will send eQSL cards for full reports.
This week’s programme has a varied mix of great classical music to enjoy. A clarinet Trio by Brahms, some of a string quartet by Beethoven – his last one – the 13th, and some singing from 12th century France. We’ve more clarinet from Mozart – to compare and contrast with the Brahms, and then two lieder from Schubert’s Winterreise – performed by Fischer-Dieskau and Alfred Brendel. The contemporary composer Meredith Monk does something extraordinary with a few instruments and the human voice before we finish with La Péri by Paul Dukas.
Both Channel 292 and WBCQ as well as WWCR can be pulled live off the internet if the reception is poor in your location. Easy to find their sites with a google search.
Thank you for spreading the word about Encore – Classical Music on Shortwave. And thank you to everyone for letting us know how well the signal is received where you live.
Brice Avery – Encore – Radio Tumbril.
Regular Broadcast times are:
15:00 – 16:00 UTC Sunday, and repeated 19:00 – 20:00 UTC Friday on 6070 kHz Channel 292 (Germany).
01:00 – 02:00 UTC Sunday on 6115 kHz WWCR (Tennessee).
01:00 – 02:00 UTC Monday on 7490 kHz WBCQ – (Maine).
For over two weeks now, I’ve had an early production model of the RSPdx here in the shack operating on a beta version of the SDRuno application.
In the spirit of full disclosure, SDRplay is a long-time supporter of the SWLing Post and I have alpha- and beta-tested a number of their products in the past. This early production RSPdx was sent to me at no cost for a frank evaluation, and that’s exactly what I’ll offer here. To be clear, while I am using beta software, this is not a beta SDR, but one from a first limited production run.
And thus far, I must say, I’m impressed with the RSPdx.
Upgrades
The RSPdx has been introduced as a replacement for the RSP2 and the RSP2pro receivers. It has been updated and upgraded, with a completely new front-end design.
Here are the highlighted improvements and changes:
Performance below 30 MHz has been enhanced when compared to the RSP2/RSP2pro.
Performance below 2 MHz has been substantially upgraded. Through the use of the new HDR mode, both dynamic range and selectivity have been considerably improved.
There is now a BNC antenna connector on antenna C position instead of a HiZ port. Both A and B antenna ports are SMA like other RSP models.
Let’s face it: those of us interested in low-cost SDRs are spoiled for choice these days. The market is chock-full of sub-$200 SDRs, especially if you include all of the various RTL-SDR-based SDRs and knock-off brands/models one can find on eBay.
Personally, I invest in companies that support radio enthusiasts for the long haul…those that do their own designs, innovations, and production. SDRplay is one of those companies.
SDRplay’s market niche has been providing customers with affordable, high-performance wideband receivers that cover an impressive 1 kHz to 2 GHz.
Wideband coverage can come at a cost. Unless you pay big money for a commercial-grade wideband receiver, you’re going to find there’s a performance compromise somewhere across the spectrum. On the RSP2 series, those compromises would have been most apparent on frequencies below 30 MHz.
That’s not to say HF, MW, and LW performance was poor on the RSP2 series–indeed, it was quite impressive and well-balanced; it just didn’t stack up to the likes of the similarly-priced AirSpy HF+ and HF+ Discovery, in my humble opinion. Both little Airspy SDRs have wooed DXers with their impressive dynamic range and overall ability to work weak signals in the HF portion of the spectrum.
Neither of the AirSpy HF+ models are wideband receivers, but still offer a generous range: 9 kHz to 31 MHz and from 60 to 260 MHz––about 11.5% of the frequency coverage of RSP models. (Note that the Airspy R2 and Mini do cover 24 – 1700 MHz.) For shortwave radio listeners that also want to venture into the UHF and SHF regions, a wideband SDR is still required.
It’s obvious SDRplay’s goal is to make the wideband RSPdx into a choice receiver for HF and, especially, for MW/LW DXers. But have they succeeded? Let’s dive in…
Performance
As I say in most of my SDR reviews: doing comparisons with receivers that have so many features and adjustments is never easy. In other words, we want an apples-to-apples comparison, but it can be difficult to achieve, especially with new products.
The RSPdx, Excalibur, and HF+ Discovery all used the same antenna in my tests––a large, horizontal delta loop antenna, via my ELAD ASA15 amplified antenna splitter. I’ve used this antenna splitter for years and can vouch for its equitable, lab-grade distribution of signal.
The RSPdx is not in full production at time of posting, thus application options are limited. Typically, I’d load comparison SDRs in SDR Console or HDSDR and test them with identical settings as well. At present, the RSPdx is only compatible with a beta version of SDRplay’s own application, SDRuno (which will come out of beta rior to the first major production run). The benefit of using SDRuno is that you unlock the full potential of the RSPdx, plus signal and noise numbers are incredibly accurate.
For each SDR in this comparison, I used their native/OEM application to give them the best possible performance.
I also matched filter settings and made an effort to match AGC and volume settings as closely as I could.
Additionally, I resisted the temptation of comparing my RSP2 with the new RSPdx because I didn’t want to run two simultaneous instances of SDRuno on the same computer––especially considering one was in beta.
Is this comparison perfect? Probably not, but I did the best with the time I had available. I do intend to make further comparisons in the future.
Longwave performance
Via the RSPdx’s new “HDR” mode, both dynamic range and selectivity have been considerably improved with frequencies below 2 MHz. While I’ll fully admit that I’m not much of a longwave DXer, my very first listening session with the RSPdx started in this region of the spectrum.
In fact, the first evening I put the RSPdx on the air and confirmed that I was, indeed, in HDR mode, I noticed a small carrier via the spectrum display on 171 kHz. I clicked on it and quickly discovered it was Medi 1. The signal was faint, but I could clearly ID at least one song. This truly impressed me because I believe this was the first time I had logged Medi 1 on longwave from the shack.
I didn’t connect the Excalibur at that point to see if it could also receive the faint Medi 1 signal, but I imagine it could have. I’m pretty sure this would have been outside the reach of the RSP2, however.
I tried to explore more of the longwave band, but due to local RFI (I suspect an appliance in my home), most of the LW band was inundated with noise. With that said, I did grab three of my benchmark non-directional beacons.
Obviously, the RSPdx is a capable LW receiver. I would like to spend more time on this band once I’ve tracked down the source of my local RFI.
Mediumwave/AM performance
In the past two weeks, I’ve spent many hours with the RSPdx on mediumwave.
We’re heading into the winter months in the northern hemisphere, and that’s normally when my listening habits head south on the bands.
In short: I find the RSPdx to be quite sensitive and selective on the mediumwave bands while the HDR mode is engaged. A major improvement over its predecessor.
I primarily compared the RSPdx with my WinRadio Excalibur on mediumwave since I consider the Excalibur to be a benchmark MW receiver. And, as you’ll hear in the screencasts below, the RSPdx truly gives the Excalibur a run for its money:
Note that my horizontal delta loop antenna is omni-directional, hence the tug-of-war you hear between stations in the clips above.
In truth, I could have done more to stabilize the signal on both of these fine SDRs, but I wanted to keep the comparison as fair as possible.
You might have noticed that both were running AM sync mode. It seems the sync lock on the RSPdx may have also improved––though I would need to do a direct comparison with the RSP2 to know for sure––but in terms of stability, I still found that the WinRadio Excalibur was superior. Mind you, the Excalibur is a $900 – $1,000 receiver and has the strongest synchronous detector of any radio I’ve ever owned.
Shortwave/HF
SDRplay notes on the preliminary specifications sheet that the RSPdx has been “enhanced” when compared with the RSP2 series.
And, after having spent two weeks with the RSPdx on the shortwave bands, I would say this is a bit of an understatement. For although I haven’t compared the RSPdx directly with the RSP2 yet, I do feel HF performance is substantially better than its predecessor. Indeed, in my comparisons, I often found it gave the Excalibur some serious competition. Overall, the Excalibur had an edge on the RSPdx, but the gap has closed substantially. That’s saying something.
For the comparison videos below, I also included the excellent AirSpy HF+ Discovery.
As you can see and hear, the RSPdx is now in the league of some of the finest HF receivers in my arsenal.
But I’m curious to know what you think after listening to these comparisons. Please comment!
Notch Filters
For those of you living in areas with DAB/DAB+ broadcasters nearby, you’ll be happy to note that the RSPdx has a DAB filter to help mitigate any potential overloading.
Also, if you live near a blowtorch mediumwave station, you’ll be quite pleased with the MW notch filter. It’s so effective at filtering out the mediumwave band, my local blowtorch on 1010 kHz is barely visible on the spectrum once the notch filter is engaged. (Note: I should add that neither the DAB nor the mediumwave notch filter was engaged during any of my previous comparisons above.) Check out the screen shots below showing the mediumwave band before and after the MW notch filter is engaged:
Before:
After:
Summary
For those of you looking for a budget wideband SDR with solid performance below 30MHz, look no further.
For $199 US, you’re getting a quality UK-designed and manufactured SDR in a proper metal housing. The OEM application, SDRuno, is one of my favorite SDR applications and can fully take advantage of the RSPdx’s new HDR mode. No doubt, with a little more time, most third-party SDR applications will also support the RSPdx.
Frankly, I was expecting classy mediumwave and longwave performance as this was the most touted upgrade of the RSPdx. SDRplay certainly delivered.
In my experience, SDRplay doesn’t oversell their products. Their preliminary product sheet mentioned improved performance on HF, but their press release didn’t even mention the HF upgrades. And this is where I, in particular, noticed significant improvement. Perhaps this is because I am primarily an SWLer, thus spend a larger portion of my time in the HF region.
SDRplay products also have a mature, robust SDR application via SDRuno. Day to day, I tend to use Simon Brown’s SDR Console as my primary SDR application, since it’s compatible with so many of my SDRs and also offers some of the best recording functionality for those of us who do audio and spectrum archiving. Each time I beta test or review an SDRplay SDR, however, I’m more and more impressed with SDRuno. It’s evolved from being a rather cluttered application to one with a thoughtful, cohesive user interface that’s a joy to use––a product of true iterative agility.
Indeed, after having used SDRuno exclusively these past two weeks, I believe I would consider it as my primary SDR application…if only it had audio recording in addition to spectrum recording, and could run multiple instances with multiple SDRs. Again, given a little time, I wouldn’t be surprised if some of this functionality is eventually integrated.
Questions?
Since many SWLing Post readers already own an SDR, I’m sure some of you will have questions. Let’s address a few of those right now.
Question: “I have an RSP2/RSP2pro. Should I upgrade to the RSPdx?”
My recommendation: If you are a shortwave, mediumwave, or longwave DXer, I would indeed recommend upgrading to the RSPdx. If you primarily use your RSP2 series SDR on frequencies above 30 MHz and only occasionally venture below for casual listening, then I’d keep the RSP2.
Question: “I have an RSP1a. Should I upgrade to the RSPdx?”
My recommendation: If you’ve been enjoying your RSP1a and would like to take your listening/monitoring to the next level, then, yes, I would upgrade. Not only can you take advantage of the RSPdx’s enhanced performance, but the RSPdx affords you three antenna ports, and has a more robust front end.
Question: “I have an RSPduo. Should I buy the RSPdx?”
My recommendation: I’m a big fan of the RSPduo. Unless you’re a dedicated mediumwave/longwave DXer, or you’d just like to add another separate SDR to your radio arsenal, I wouldn’t rush out to buy the RSPdx.
And while I’m offering advice, I’d like to offer my standard two cents on the subject of performance optimization: a radio is only as good as its antenna!If you have a compromised antenna, invest in your antenna before upgrading your radio. You’ll be glad you did.
Conclusion
Happily, I can recommend the SDRplay RSPdx without hesitation. This latest iteration of the RSP series SDR is a proper step forward in terms of performance and functionality––obviously implementing years of customer feedback.
SDRplay also has a proven track record of innovation and customer support. Their documentation, video tutorials, and community are among the best in the industry. Purchase with confidence.
