Tag Archives: DSP

Advice on cancelling locally generated noise

An SWLing Post reader recently contacted me with the following question:

“What devices work well to cancel out local RFI? I’ve been told that both the Timewave ANC-4 and a number of BHI products are all worth considering.”

Unfortunately (or fortunately, for me) I’ve no experience with outboard DSP or noise cancelling devices because I live in such an RFI-free area.

I know this reader already has a Wellbrook Loop, but he’s looking for a way to even increase noise mitigation further at his home listening post.

Post Readers: Can you help guide him?  Please comment with your experience. Is a product like the Timewave or BHI the next logical step? If not, what is?

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Phil demonstrates the BHI NEIM1031 Noise Eliminating In-Line Module

bhi-dsp

Many thanks to SWLing Post contributor, Phil Brennan, who writes:

[Recently] one of your contributors mentioned that he purchased a BHI DSP unit at a discounted price. I purchased one (a different model to the one in the previous post) some months ago before I headed away travelling.

The post reminded me that I had made a small video demonstrating the DSP unit on my FRG7. The video shows me tuning the DSP on a broadcast of Voice of the People on 3912 khz. While QRM at my place isn’t too bad, it’s still present and the DSP does aid in clearing up a signal.

Voice of the People is usually jammed by the DPRK and the DSP also assists in reducing the roar of the jammer. Of course one can go to far with DSP and the audio can suffer from that underwater sound.

Thank you, Phil! The FRG-7 is an ideal receiver for something like the BHI module since it precedes on-board DSP. The great thing about an in-line module, of course, is that it can be used with a variety of receivers.

Click here to view the BHI NEIM1031 MKII on BHI’s website.

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Very Scarce Kneisner + Doering KWZ-30 DSP Receiver Surfaces on Ebay

Hailing from Germany, the KWZ-30 communications receiver was one of the first DSP receivers available. This collectable and high performance receiver is rarely seen for sale, but one is now available for a $1890.00 Buy-It-Now price from a Russian Ebay seller. Even with the few dings visible on the radio’s case, it’s likely worth the asking price to a collector.

KWZ-30

The extensive Fenu-Radio web site has a nice capsule review of the KWZ-30, including some excellent photos.

At the $1890.00 price of this KWZ-30, you could buy a dozen SDRPlay receivers, or roughly a couple of the highly rated Perseus SDRs. Assuming available funds, is the KWZ-30 a receiver you would add to your radio shack? If so, why… or why not?

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

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The ShouYu SY-DP-330: a retro, x-bass shortwave radio

shouyu-dp330

The Professor recently sent me a link to the ShouYu SY-DP-330–stating it must be the “big brother” of the ShouYu SY-X5. Indeed it is! The DP-330 sports all of the features found in the SY-X5. It is very large in comparison, though, and runs on four D batteries. The DP-330 even comes with a remote control–most likely for the built-in MP3 player.

On a side note, the DP-330 is in the only shortwave radio advert I’ve ever seen that also features a giant mega-mechanical monster robot. Classy!

Do any readers have the DP-330? Please share your comments.

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Chorus 4: The DSP chip that supports AM, FM, DAB, DAB+, HD Radio and DRM

FrontierSiliconThe London-based digital solutions company, Frontier Silicon, has announced a new DSP radio chip that offers a wide array of available modes and is even DRM ready.

I have seen no specifications for this chip yet, and do not know if it covers the shortwave radio spectrum.

Still, this might be the perfect chip to allow radio manufactures to design an inexpensive, fully digital product in countries where digital platforms are gaining strength (anywhere from the UK to India, for example).

Many thanks to Rob De Santos for apprising me of this. I’ll post the specifications when they become available. Read the full press release below:


(Source: Frontier Silicon Press Release)

Chorus 4 a single-chip solution, integrating four previously separate chips

London, 17th December 2013

Frontier Silicon announces details of Chorus 4, its next generation digital radio chip. Chorus 4 is a single-chip solution, which integrates four previously separate chips to deliver significant cost and energy consumption savings.

Chorus 4 is the fourth generation chip from Frontier Silicon. The chip is designed to encourage the continued advance of digital radio around the world by supporting all major global digital radio standards. Chorus 4 provides solutions for multiple devices, including consumer radios, the automotive aftermarket and, for the first time, smartphones and tablets. The company’s previous solutions have already powered over 20 million digital radios worldwide.

The key features and benefits of Chorus 4 are:

  • Low cost, single chip solution: integration of RF front-end, baseband, application processor and DAC (“four chips in one”) delivers significant cost savings which enable high quality, entry-level price point digital radios
  • Ultra-low power consumption – one month’s listening for 5-6 hours a day on a portable radio with four D cell batteries (comparable to FM performance)
  • Multiple solutions for portable and table-top radios, smart-device docks, wireless speakers, hand-held receivers, sound-bars and audio systems
  • Automotive aftermarket – solutions for head units, integrated convertors and low cost adapters
  • Smart devices – enables digital radio solutions for mobile phones and tablets
  • Bluetooth connectivity – connecting smart devices and digital radios to enable hybrid radio (with interactivity and additional content delivered via IP), music streaming and remote control
  • Integrated service guides – new software will enable listeners to select stations from a single list of digital and analogue stations regardless of platform
  • Multiple radio standards – including support for AM, FM, DAB, DAB+, HD Radio and DRM

Digital Tick compliant – Chorus 4 solutions meet all technology requirements of the UK minimum specifications for both domestic and automotive digital radio devices.
Frontier Silicon CEO, Anthony Sethill, said

“Chorus 4 represents a step change for the digital radio market. After ten years of development on this and previous solutions, we now have our fourth generation chip – an integrated, single chip offering enhanced functionality, lower cost and significantly greater energy efficiency. Chorus 4 will power multiple devices, including low cost automotive adapters and devices with Bluetooth connectivity. For the first time, digital radio in mass deployment smartphones will become a viable proposition. As a multi-standard chip, Chorus 4 will address emerging opportunities around the world. I look forward to working closely with broadcasters, transmission operators and device manufacturing partners to address these exciting opportunities.”

About Frontier Silicon Limited

Frontier Silicon is the world’s leading supplier of integrated circuits and modules for digital radio and connected audio products. Frontier Silicon is part of the Toumaz Group, a pioneer in low-power wireless semiconductor and software technologies for the consumer audio and wireless healthcare markets.

The group is headquartered in London, England, with design centres in Oxford, Cambridge, Hong Kong and Romania. The company also has sales and technical support teams in Hong Kong, China and Japan.

Frontier Silicon’s audio products offer solutions for DAB/DAB+, Internet radio and connected audio – from silicon through software to production-ready platform designs.

Customers supplied by Frontier Silicon include Argon, Bang & Olufsen, Bose, Bush, Denon, Dual, Geneva, Goodmans, Grundig, Hama, harman/kardon, Hitachi, JVC, Magic Box, NAD, Onkyo, Panasonic, Philips, Pinell, Pioneer, Pure, Revo, Roberts, Ruark Audio, Sangean, Sanyo, Sharp, Sony, TEAC, TechniSat, Tivoli Audio and Yamaha.

Frontier Silicon is a trademark or registered trademark of Frontier Silicon Ltd.

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A review of the ShouYu SY-X5 DSP shortwave radio

The Shouyu SY-X5 mechanically-tuned, DSP portable radio. (Click to enlarge)

The Shouyu SY-X5 mechanically-tuned, DSP portable radio. (Click to enlarge)

The ShouYu SY-X5 shortwave radio came to my attention only a few weeks ago. It is yet one more mechanically-tuned, DSP based, portable shortwave/AM/FM radio. I have reviewed several other models based on the same DSP chipset: the Silicon Labs SI4844–see my reviews of the Degen DE321, Degen DE32, and the Kichbo KK-9803. I also recently reviewed the Tecsun R-2010D, though it is based on a slightly newer, though similar, SiLabs DSP chipset.

What makes the ShouYu SY-X5 stand out is the fact that it can be powered by either a rechargeable slim battery pack (found in the DE32) or three standard AA batteries.  It also has a built-in MP3 player that uses a standard microSD card for media storage. Why are these features of particular note for me?  I have been searching for a shortwave radio/mp3 player for use by my charitable non-profit, Ears To Our World. ETOW works in parts of the world where people lack mains power as well as access to the Internet (or else simply can’t afford Internet service). In such settings, radio allows teachers and school children to hear up-to-date international news via shortwave, and through pre-recorded educational material, they can play (and replay) MP3 content as needed.

Therefore, I immediately ordered an SY-X5 for review here, hoping to donate it for use in the field care of Ears To Our World.

First impressions

Degen DE321 (left) Shouyu SY-X5 (right)

Degen DE321 (left) Shouyu SY-X5 (right)

The ShouYu SY-X5 is a small radio, almost exactly the same size as the very portable Grundig G6 and only slightly larger than the Degen DE321 (see left). It feels sturdy and even slightly heavy in your hand (no doubt, due to the number of batteries it holds). The antenna is rotatable and feels more robust than other radios in its price class.

The SY-X5 has a back stand that likewise feels sturdy enough. Note: to open the battery compartment, you must lift up the back stand.

The overall quality is better than one might expect for $27 (US), with one notable exception: the printed frequency display behind the analog dial on my unit is positioned slightly off-center and not level, making needle position on the dial, well, frankly ambiguous.

Audio

Without a doubt, the greatest aspect of the SY-X5 is the audio delivered from the built-in speaker. It is exceptional for this size radio, full and with impressive bass characteristics. It very much reminds me of the Melson M7 (not yet reviewed here) and the Degen DE1129.

(Click to enlarge)

(Click to enlarge)

Performance

I’ve reviewed enough of these mechanically-tuned DSP-based radios now that I’m beginning to note performance commonalities that can only be attributed to the design of the DSP chipset itself (regardless of how they are implemented in each model of radio).

At risk of sounding like a broken record, this radio’s sensitivity, selectivity and AGC performance is nearly identical to the Degen DE321 on every band; here’s a summary:

  • Shortwave
    • sensitivity is mediocre–expect to hear all strong stations
    • AGC circuit has difficulty coping with weak station and fading
    • selectivity is mediocre
  • Medium Wave (AM)
    • strong daytime stations sound great
    • the SY-X5’s AGC circuit struggles with night time conditions, even with some strong stations
    • selectivity is mediocre
  • FM
    • FM performance is quite good
    • Both selectivity and sensitivity are great for the price–in this case, $27 US
(Click to enlarge)

(Click to enlarge)

Between the two FM bands, the SY-X5 should easily accommodate world-wide FM broadcasts (even Russia). The two AM (medium wave) bands are almost identical in frequency allocation, but have been set up so that one is on 9 kHz spacing and the other on the 10 kHz spacing typically used here in North America (nice touch).

Tuning

While the “feel” of the tuning wheel on the right side of the radio seems smooth, in reality it is not. The tension or actual mechanics behind the analog tuner are problematic; I find that upon tuning in even a strong station, when I let go of the tuning wheel, it immediately moves off-frequency. It’s most annoying. Over the course of several days of use, it doesn’t seem that the mechanism has broken in at all as I had hoped. This is perhaps the biggest negative of the ShouYu SY-X5; it is just not easy to accurately tune it.

(Click to enlarge)

(Click to enlarge)

MP3 Player

While I haven’t spent hours using the MP3 player, I find that it’s simple, yet quite effective. Most notably, it lacks fast-forward and reverse controls, though it does have buttons for ten-second skips both in the forward and reverse directions. Of course, you can pause, stop and skip to next/previous MP3 files.

The SY-X5 has a dedicated MP3 player red LED display; it is very bright–almost too bright, in fact, for low light conditions–and quite simple, offering only basic functions (no alpha-numeric tags, for example). Unfortunately, I find that the LED display does inject a little noise into the audio, but it’s nothing that would deter me from using it with the built-in speaker.

(Click to enlarge)

(Click to enlarge)

Summary

Every radio has positive and negative attributes; below are the pros and cons I noted from the moment I unpacked the SY-X5:

Pros:

  • Audio from internal speaker excellent for size
  • Integrated digital audio player
    • Uses standard Micro SD card for storage
    • Very bright red LED display (see con)
    • Dedicated, tactile buttons for basic MP3 functions
  • Multiple power sources
    • Internal rechargeable slim battery pack
    • Standard AA batteries
    • Charged/powered via standard mini USB cable
  • Relatively sturdy construction
  • Good FM sensitivity
  • Tuning indicator light
  • Inexpensive
(Click to enlarge)

(Click to enlarge)

Cons:

  • “Sticky” tuning wheel/dial results in immediate and annoying digital “drift” off-frequency
  • Sloppy selectivity (typical of this class of mechanically-tuned DSP radios)
  • MP3 player’s LED display almost too bright for low light settings; the LED does inject some slight noise into the headphone amp chain
  • Shortwave and medium wave sensitivity is mediocre, typical of other SiLabs SI484X radios
  • MP3 capabilities are only as a player, the SY-X5 cannot record in any capacity
  • Analog dial is small enough to make tuning accurately quite difficult
  • The dial’s printed frequency display in my unit is positioned off-center and tilted, resulting in ambiguous needle alignment

Conclusion

The ShouYu SU-X5 is very similar, performance-wise, to the Degen DE321. Out of all of the mechanically-tuned DSP portables reviewed thus far, the SY-X5 may have the best audio fidelity via its built-in speaker (save the Tecsun R-2010D). Also, like other similarly sized and priced models in this family, the SY-X5 has tuning issues; in its case, a tuning wheel that will not stay on frequency without practice.

(Click to enlarge)

(Click to enlarge)

I’ve decided to take my SY-X5, on behalf of Ears To Our World, to inner Belize City in the near future. I’m going to offer this radio–together with a microSD card packed with VOA Special English programming (and a host of other English language educational materials, music and stories)–to a visually-impaired, economically-disadvantaged school child who will hopefully give this basic little radio lots of use, and perhaps even maximize its potential. While the SY-X5 has shortcomings, for this particular use–serving an individual who will not rely primarily on sight, but on tactile response, to operate it–I think it may serve its purpose. Perhaps this will be the best litmus test for the SY-X5’s utility and longevity:  I may post an update when I receive feedback in approximately one year, as to whether this radio has required repair, replacement, or has offered (as I sincerely hope!) some measure of benefit to the child-owner.

For the radio hobbyist, I would encourage you to skip the ShouYu S-X5 and, instead, invest in a Tecsun PL-380, PL-390, PL-398BT, Degen DE1102, DE1103, or the Tecsun PL-600. Though all are pricier, each is under $100 US, and will actually provide a lot of performance for the price. The SY-X5 and other mechanically-tuned DSP radios seem only to offer mediocre performance and a low price.
Click here to search for the Shouyu SY-X5 on eBay.

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New product: the ShouYu SY-X5 shortwave radio

The ShouYu SY-X5

The ShouYu SY-X5

[Update: Check out our review of the SY-X5 by clicking here.]

Thanks to Paul, I just found out about the ShouYu SY-X5: a new analog DSP-based shortwave radio with built-in MP3 player. Like the Degen DE321DE32Kchibo KK-9803 and the recently released Tecsun R-2010D, the SY-X5 has a mechanical tuning mechanism powered by a Silicon Labs DSP chip.

I just purchased the ShouYu SY-X5 from this seller on eBay. The total cost was $27 US including shipping from Hong Kong. There are other sellers offering the SY-X5 on eBay, but their prices are almost double (with shipping from the US).

At a low price of $27 US, my expectations will be adjusted accordingly. My hopes are somewhat higher for the Tecsun R-2010D as Tecsun tends to do a better implementation of DSP chips than their competitors. Since I’ll be receiving both units within days of each other–and I still have the DE321 and DE32–I will certainly compare them.

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