Category Archives: Shortwave Radio

Silphase R1 videos and information about power and antenna ports

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We’re starting to get a little more info about the recently posted Silphase R1 SDR receiver. At this point, the radio isn’t in production and is obviously only in a prototype stage so there are a lot of question marks–including if it’ll ever come to fruition. The pandemic is obviously not an ideal time to launch and produce a new high-end radio. I, for one, certainly hope they do!

Many thanks to SWLing Post contributor, Mark Hirst asked Silphase about R1 external antenna support and power options. A Silphase representative replied:

“We are constantly redesigning the rear panel receiver Silphase R1, so we
can say for sure that there are 4 connectors – antenna F-type connector,
12.6 V power/charging, RJ-45 and USB”

And thanks to SWLing Post contributor, Paul, who received the following info from Silphase:

You can watch real videos on our YouTube channel.

https://www.youtube.com/channel/UCQN8YbKULHlkA4KBFt76Hhg

Sample videos:

Click here to view all of the videos on the Silphase YouTube channel.

As we learn more about the Siplase R1, we’ll publish it on the Post with the tag: R1.

Converting Tecsun signal meter numbers into five strength units?

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Many thanks to SWLing Post contributor, Chris Rolfe (M3OZP), who writes with the following inquiry:

Don’t know if anyone can help.

I have a Tecsun PL-880, and it shows signal strength in db. How can I work out the signal strength as 1 to 5? All my other radio have 1 to 5 signal strength meters which is what I have always been used to.

Many thanks.

Chris Rolfe
M3OZP

Thank you for your question, Chris. The signal meter on the PL-880 and a number of other late-model Tecsuns that use similar DSP chips share the signal display which indicates both the signal strength and signal-to-noise ratio.  I believe the dBu number indicates the conducted voltage across the receiver’s internal resistance.

It’s perhaps one of my quirks, but as a listener I actually pay little attention to signal displays on portables unless I’m evaluating signal strength for a report or even using it to locate a local noise. Converting those numbers into an S1 to S5 number is simply something I would do by “guesstimating.” Yeah, not terribly scientific.

There are folks in the SWLing Post community who can do a much better job explaining the readout and how to interpret/convert signal strength across the MW, SW and FM bands.

Post Readers: Please comment if you can shed some light on simplifying signal strength for Chris.

Giuseppe’s reception of the LRA36 test broadcast

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Photo from the Argentine Antarctic Base (LRA36) – Source: RAE

Many thanks to SWLing Post contributor, Giuseppe Morlè (IZ0GZW), who shares the following:

Dear Thomas

Here is the link of to video regarding the transmission of LRA 36 in USB mode Saturday July 25, 2020 from 17.00 UTC on 15.476 MHz.

A good result if I think it was almost impossible to listen to it with the sun still high … the place where I listen, in Formia, Italy, is really excellent.

73. Giuseppe Morlè iz0gzw.

Thank you for sharing this, Giuseppe! I’m always impressed with the DX you catch there at your location in Formia! Grazie e ciao!

Finally confirmed reception of LRA36 Radio Nacional Arcángel San Gabriel Antarctica

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For years now I’ve attempted to get decent reception of LRA36 Radio Nacional Arcángel San Gabriel in Antarctica. At times, I’ve been able to barely hear their AM signal here in North Carolina–at least, see it as a faint line on my spectrum display and barely hear audio rise above the noise. But in truth I could never confirm anything more than “male voice” and “music” thus never bothered with a report in good faith.

Recently, we’ve posted announcements for a series of test broadcasts from LRA36 in single sideband (SSB). Two weekends ago, I couldn’t receive a single inkling of their signal, but this past Saturday, I finally heard the station well enough to submit a detailed report and recording in confidence.

I had actually set my SDR to record 20 kHz of spectrum at home while I made my first CW POTA activation at the nearby Blue Ridge Parkway. A pop-up storm chased me away from the POTA site and it worried me that I had left my SDR running and connected to the antenna. Fortunately, none of the small thunder storms were directly over my home. Although there was heavy QRN due to local pop-up thunderstorms, their signal was there.

The following sample recording starts at 17:51 UTC  (July 25, 2020) on 15476 kHz.  It’s weak signal DX for sure, but interpretable. I made the recording with my WinRadio Excalibur SDR hooked up to a large Skyloop antenna. This clip starts with the song  Juana Azurduy by Mercedes Sosa:

I’m so chuffed to add the LRA36 QSL to my collection! Broadcasting in SSB made all the difference!

Have you successfully logged LRA36 from your home?  Please comment!

The new Silphase R1 SDR receiver

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I’ve just learned about a new SDR receiver in development by the Polish company Silphase. It’s called the Silphase R1 and appears to be a stand-alone, high-performance SDR receiver.

What could set this receiver apart from the rest is the:

  • Color backlit 5″ TFT touch screen display
  • Magnesium alloy body/chassis
  • USB out for recording and native logging
  • Record to internal “flash memory” (unclear if audio and/or spectrum)
  • Four internal speakers
  • 12.6V 12000 mAh, internal battery
  • IP55 rating for water/dust protection
  • The price is $1199/€1099 with no expected availability date at time of posting
  • Click here to download the PDF product brochure.

The receiver is portable and will measure 11.25×4.3×2.2in (285×110×55mm). Looks like the screen will be 5″ which should allow for a detailed spectrum viewing area (for comparison, the Icom IC-7300 TFT display is 4.3″)

Siphase is a new company based in Poland and they claim they also plan to eventually produce transceivers:

“At the end of 2020 we will introduce a 25W transceiver in the same form factor powered by an internal battery, and a bit little later a 100W transceiver in the same form factor also powered by an internal battery.”

The Silphase product page has a complete list of specifications, but here are some worth noting:

  • Frequency coverage RX 0.1–30MHz
  • Frequency resolution 1Hz
  • Frequency steps 1Hz to 1KHz
  • Dual VFO
  • Direct sampling 16bit high speed 122 M/s ADC
  • Modes: CW, SSB, AM, FM
  • Sensitivity 1.8–29.999MHz, SSB/CW: (BW: 2.4kHz at 10dB S/N) – 132 dBm, 0.06?V
  • 20dB LNA
  • Spurious and image rejection >90 dBm
  • Clipping level -3dBm
  • DSP (various filters, adaptive noise reduction, automatic notch filter, notch blanker, adjustable filters (0-1KHz HPF,0.5-6KHZ LPF, 50Hz step, etc.)
  • AGC (slow, medium, fast)
  • Main filter sharpness Factor 1.05 and lower
  • Audio recorder (use the internal flash memory or USB 16GB external flash memory)
  • Virtual USB audio card for OS update
  • Ham radio hardware log
  • OS QNX (“UNIX-like” real time operating system)
  • Telescopic antenna with F connector
  • Main optical encoder and four multifunction encoders
  • 6 input modes buttons (attenuators, adjustable filters, AGC, NB, auto notch filter, NR)
  • Power supply requirement 12.6 DC ±15%
  • Power consumption RX 0.6 A typical
  • Battery 12000 mAh, 12.6V (3×3.7V/12000 mAh)
  • Operating time 20 Hours
  • Operating temperature range –10C to +60C; 14F to 140F
  • Frequency stability Less than ±0.2ppm (–10?C to +60?C; 14?F to 140?F)
  • Dimensions (W×H×D) 285×110×55mm; 11.25×4.3×2.2in
  • Weight (approximately) 1.8kg; 4 lbs
  • Magnesium alloy body, IP55 (in future IP 67)
  • “Expected Operational Lifetime 30 Years” With One Year Warranty – Additional Warranty
  • Made in EU

As I learn more about this receiver and the company producing it, I’ll post updates with the tag: Silphase R1

Click here to check out the Silphase website.

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Tom’s amazing 1986 Voyager Experimental Aircraft flight communications recording and QSL card

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The Voyager aircraft circles before landing at Edwards Air Force Base (Source: NASA via Wikimedia)

One of the most amazing things about hosting and curating a massive collection of shortwave radio recordings is listening to each recording as they’re published on the Shortwave Radio Audio Archive (SRAA).

SRAA contributor, Tom Gavaras, has shared some brilliant off-air and studio recordings over the years including the following shortwave recording of Voyager Experimental Aircraft flight communications with Dick Rutan and Jeana Yeager in 1986.

I haven’t even published the recording on the archive yet, as he just submitted it. Tom notes:

Rutan Model 76 Voyager Experimental Aircraft was the first aircraft to fly around the world without stopping or refueling.

It was piloted by Dick Rutan and Jeana Yeager.

The flight took off from Edwards Air Force Base’s runway in the Mojave Desert on December 14, 1986, and ended 9 days later on December 23, setting a flight endurance record.

This shortwave recording is a sample of some of the communications between Dick Rutan and his ground crew including a debate if Dick should walk out of the aircraft after it lands.

Tom made this recording with an ICOM R71A receiver in Minnetonka, MN, and believes the date of this recording is December 22, 1986:

QSL card

This is simply amazing, Tom! Thank you so much for sharing your recording and QSL card with us. A proper radio treasure!

Post readers: click here to check out the Shortwave Radio Audio Archive and click here to browse some of Tom’s contributions. Also, click here to read our previous post about Tom’s amazing RadioTapes.com website.