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Old 04-05-2018, 19:38   #91
tpreitzel
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Jerry contacted me today and asked me to basically return my GR-216. I informed Jerry that my GR-216 is now working again so I'll keep it unless it becomes unusable. I asked Jerry when he expects updated firmware for the GR-216, but haven't received a response yet. Jerry also said that he's leaving Gospell for other endeavors and a Mr. Michael (probably first name) is replacing him at Gospell.

Thanks, Jerry, and best wishes!

Last edited by tpreitzel : 04-05-2018 at 21:18.
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Old 08-05-2018, 12:34   #92
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Is the fast recording with FM a bug or a feature in r1.4 of the GR-216's software? The "Radio Recoder" works well with AM, but not FM. BTW, please change the typographical error from "Radio Recoder" to "Radio Recorder". I know Gospell wants the GR-216 to be as professional a DRM receiver as it can be.

BTW, I read Ken Reitz's review of the GR-216 in the May 2018 issue of the "Spectrum Monitor". Although I agreed with the majority of Ken's review, I also disagreed with a significant percentage, ~ 1/3. Ken basically rehashes the prevailing perceptions of DRM, but never really analyzes the reasons behind them. Digital broadcasters' poor configurations are the primary reason behind those prevailing perceptions, not the DRM standard itself. I disagree that the quality of the speaker's audio is "unremarkable". I've posted recorded samples for listeners to judge for themselves. The market for the GR-216 doesn't require SSB under any circumstances. Although the tuning is somewhat quirky, it's functional. I agree with Ken that the selectivity of the GR-216 could be better, though. Although my GR-216 certainly wasn't certified by the FCC, Gospell did include an 110V power supply in it so 220V certainly isn't mandatory. Instead of fussing over SSB, the inclusion of a COMPACT IR remote control would certainly be a nice addition to the GR-216. I also agree that a standalone DRM receiver is a far smarter idea than a kludge consisting of a computer, analog receiver, and DReaM. As listeners grow older, they tire of the complexity.

I'm not nearly as pessimistic as some people over the state of DRM. The standard is fully capable even if current digital SW broadcasters are not.
I suspect that someone like Allan Weiner of WBCQ will be needed to promote DRM in North America. Allan understands the viability of radio, especially SW, in light of ubiquitous governmental snooping through proxies such as the SpyNet and SpyPhone. Everyday, the mountain of illegal spying by corporations and governments continues to rise. Today, it might be Facebook. Yesterday, the culprit was the NSA as exposed by E. Snowden. Radio circumvents such invasions of privacy and digital radio provides a flexible means to communicate. Allan or someone with his philosphy is the perfect candidate to conduct this digital orchestra over shortwave.

Last edited by tpreitzel : 09-05-2018 at 03:28.
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Old 08-05-2018, 12:34   #93
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Evidently, Gospell uses IMA ADPCM, 16 bit, 44100 Hz, stereo. I'm trying to find the equivalent codec in FFMPEG which allows for conversion to other formats.

I've found a way to playback nearly ANY file using the "Radio Recorder" in the GR-216. However, the missing header can cause strange behavior...beware. Naturally, the "Radio Recorder" was designed to record and play audio from AM & FM stations on the GR-216, not external files.

Regardless, this conversion process using FFMPEG should work alright to hear audio.

ffmpeg -i input_filename output_filename.wav -codec:a adpcm_ima_qt

WARNING:
As Ken stated, the output levels are way, WAY too high to the GR-216's speakers so reduce DRASTICALLY the levels of the files after converting them to WAV audio, i.e. normalize the files to -32dBFS.

I'm sure another way exists or will soon exist to playback files not recorded on the GR-216, but I wanted to investigate the format anyway.

Last edited by tpreitzel : 15-05-2018 at 02:19.
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Old 15-05-2018, 04:42   #94
tpreitzel
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GR-216 r 1.4 BUGS

Some bugs which come to my mind:

1. Hardware lock-up with no audio which nearly "bricked" my GR-216.
A variant of this bug is one where the audio just dies. The power to the GR-216 must be recycled for the audio to return, but no hardware lock-up occurs.
2. DRM decoding which requires SNRs above 19dB from Radio Kuwait.
3. Playback bug in "Radio Recorder", most noticeable on FM recordings
4. Excessive audio levels to output transducers except possibly the headphone output.
5. Logging bugs ... driving me nearly batty.
6. FF FR searching bug which causes frequency bar to disappear with only a visible triangle for the cursor.

I'm sure other bugs exist.

Last edited by tpreitzel : 10-06-2018 at 02:58.
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Old 17-05-2018, 05:25   #95
alokesh
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AVION DRM DIGITAL RECEIVER UPGRADED

Communications Systems Inc. in India, the manufacturer of the Avion DRM digital receiver AV-1401, have started their second production after undertaking several enhancements to the device.

They have upgraded the model AV-DR-1401 with a new PCB design with enhanced sensitivity, and improved FM signal. The screen benefits from a change of the front lens into crystal die giving an improvement to the big LCD window. The manufacturer has also upgraded the software for the Emergency Warning Functionality, so that it can be used when the receiver is in standby as well. Moreover, the receiver is now able to pick up weaker signals delivering those in better digital audio quality. Improvements have been done also on the antenna by providing a complete new design.

Desktop radios are also being produced in India (http://www.avionelectronics.in) and more models should be announced once the digital broadcast has officially been communicated and started. It is learnt that orders are being received even for xport of DRM radios.

Currently the new receiver can be bought by contacting the manufacturer on info@avionelectronics.in Delivery is by Fedex/UPS.

http://www.drm.org/avion-drm-digital-receiver-upgraded/
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Old 17-05-2018, 16:19   #96
tpreitzel
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Alokesh,

Thanks for the information on a new hardware revision of the DR-1401. Competition is good and shows the improving state of DRM in India and elsewhere.
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Old 17-05-2018, 16:28   #97
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The release of Titus II DRM receiver has been further delayed by three months due to integration of Fraunhofer's mm player, expected by Aug/Sept 2018.
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Old 17-05-2018, 17:00   #98
tpreitzel
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Quote:
Originally Posted by alokesh
The release of Titus II DRM receiver has been further delayed by three months due to integration of Fraunhofer's mm player, expected by Aug/Sept 2018.

This delay isn't really a surprise to me. At least, a well-debugged module from Fraunhofer is being adapted for the Titus 2. I expect further delays even beyond the fall of 2018.

A software version of a digital radio is probably the BEST idea. However, without superb technical expertise by IN-HOUSE developers, coding must be either contracted or purchased which results in a kludge of copyrights, etc. I'm just not sold on the idea as it's currently presented. I hope it works. I'd be much more hopeful if ALL coding was performed IN-HOUSE. Chuck Moore, the brilliant developer of Forth, was always reticent about the widespread use of buggy tool-kits for software development and a kludge like this one would probably drive him up a wall. As I stated in a previous post, the concept of converting hardware logic into software can work superbly, but development is generally done IN-HOUSE by immensely capable coders. Again, I hope it works ... at least acceptably.

Last edited by tpreitzel : 17-05-2018 at 21:38.
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Old 21-05-2018, 03:03   #99
tpreitzel
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Despite the bugs, I like the "Radio Recorder" option in R 1.4 of the GR-216's software. I tested it with the SW Radiogram broadcasts this weekend and it performed just fine. Personally, I think ALL DRM receivers should include the necessary software to decode the more prominent, free digital modes on shortwave as well as DRM. However, this latter capability isn't a necessity by any means.

Currently, I just record the SW broadcast and then transfer the file to a computer running FLDigi.

Last edited by tpreitzel : 21-05-2018 at 03:11.
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Old 21-05-2018, 03:04   #100
tpreitzel
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I was comparing reception on SW between my excellent magnetic loop and the whip antenna of my GR-216 earlier today. Except for a modestly stronger signal with less noise, the installed whip performed quite well in comparison. Remember, my magnetic loop costs $500. Even so, I compared the whip at 30" instead of its standard 36" length so the discrepancy would have been somewhat less if the whip had been fully extended.

I'm seriously thinking of selling my two SDR-4+ receivers, Sangean HDR-18, and Tecsun PL-880 receivers which are all great. I'll likely buy a Sangean HDR-14 to supplement my GR-216. I'll have less gear with nearly equal capability, i.e. two radios instead of five. Then again, I just might keep all of it as I'm slowly using the equipment to death anyway. If Gospell's GR-216 only included a compact remote control for a shirt's pocket...it's THAT important to me as I'm a busy person. I'll keep my magnetic loop, but the GR-216 certainly doesn't need it except in chasing ultra-weak signals from thousands of miles away.

Now, I'm waiting on Gospell to help the GR-216 to shine by fixing those software bugs in post http://drmrx.org/forum/showpost.php?...4&postcount=94

Last edited by tpreitzel : 11-06-2018 at 11:33.
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Old 22-06-2018, 02:50   #101
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receivers fitted in India OEM vehicles?
can anyone close to the market supply details of the radios in the new cars in India? my next car is likely to be a Suzuki and I'd like to specify that radio instead of DAB which shuts down next week in NZ leaving DRM the sole digital audio broadcasting going forward. My living room portable being a Pure Evoke -1 xt will also go dark. RIP DAB.
Ralph
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Old 08-07-2018, 03:14   #102
tpreitzel
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I'm inquiring with CSI about their upgraded DR-1401. Although I don't really need another xHE-AAC receiver, two are better than one for comparative purposes.

Personally, I think BOTH of the current xHE-AAC receivers are sufficiently sensitive and usable. Digital broadcasters' failure to use the xHE-AAC codec is certainly NOT acceptable. Hopefully, WBCQ will start to remedy this problem once and for all.

Last edited by tpreitzel : 08-07-2018 at 21:06.
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Old 08-07-2018, 21:58   #103
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Any more news on the GR227? This is likely the only way to do car radio if we cant get India specific tuners as OEM in vehicles.

I had a look last night for the AIR pure DRM service 870kW on 1071, as well as the 20kW services.
http://www.drm.org/wp-content/upload...WIDE-A18-5.pdf
The power figures dont quite add up, but by any measure thats quite a strong MW signal
Nothing digital detected however I probably wouldnt be able to decode if its xHE-AAC - which I agree it should be
Ralph



Quote:
Originally Posted by tpreitzel
I'm inquiring with CSI about their upgraded DR-1401. Although I don't really need another xHE-AAC receiver, two are better than one for comparative purposes.

Personally, I think BOTH of the current xHE-AAC receivers are sufficiently sensitive and usable. Digital broadcasters' failure to use the xHE-AAC codec is certainly NOT acceptable. Hopefully, WBCQ will start to remedy this problem once and for all.
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Old 08-07-2018, 23:38   #104
tpreitzel
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Quote:
Originally Posted by Aetheradio
Any more news on the GR227? This is likely the only way to do car radio if we cant get India specific tuners as OEM in vehicles.

I had a look last night for the AIR pure DRM service 870kW on 1071, as well as the 20kW services.
http://www.drm.org/wp-content/upload...WIDE-A18-5.pdf
The power figures dont quite add up, but by any measure thats quite a strong MW signal
Nothing digital detected however I probably wouldnt be able to decode if its xHE-AAC - which I agree it should be
Ralph

Ralph,

I don't know. I really need to look into the GR-227 as well. Alokesh mentioned to me that AIR hasn't been broadcasting digital on some of their stronger MW frequencies since late last year. I certainly would appreciate you keeping your ears and eyes open for any such strong digital MW stations out of India. Yeah, it's nearly crazy that we still can't encourage digital SW and MW broadcasters to use xHE-AAC in 2018.
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Old 09-07-2018, 07:27   #105
Aetheradio
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Info on what AIR is exactly transmitting is patchy, I found the transmitters listed by Nautel differ from whats shown as active on the "official" site

https://batchgeo.com/map/017ad9e7d2b...36e888f03a43dc

http://www.drm.org/wp-content/upload...WIDE-A18-5.pdf

It does appear that simulcast means DRM is on the channel 9kHz low from the AM frequency
Really need someone closer to do a scan like this:

https://www.youtube.com/watch?v=Osrc-Wa3KxQ

I note that many of the US stations limit their audio to 5kHz - perfect for DRM simulcast
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