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Old 20-06-2015, 20:31   #31
tpreitzel
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I received my analog AM stereo transmitter, ASMAX-1, recently from ASPiSYS in Greece. DRM on the MW band will be pressed hard to achieve such quality. On a high quality receiver, e.g. Meduci MW-2, the sound from the ASMAX-1 is awesome, except for one thing, hum. I'm sure that I can solve the problem with hum eventually. I'm continuing testing.

However, except for the quality of the sound (mainly useful for musical sources), the overall experience for a listener is significantly better with the DRMAX-1 transmitter or DRM on the MW band. DRM is just too flexible, solves significant problems with receiving analog broadcasts, and is potentially much simpler to deploy for the listener even on the MW band. On shortwave, the disparity between DRM and analog is even greater. I write from experience. I do confess, however, that AM stereo can blow one's mind with quality WHEN interference is eliminated and a quality receiver is used.

Last edited by tpreitzel : 20-06-2015 at 20:34.
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Old 20-06-2015, 23:06   #32
Aetheradio
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good results. Do you have any comparison recordings of RNZI when they broadcast DRM and AM simultaneously using their same power (PEP capability wise ) transmitters? I can always get a fair AM signal but rarely get any audio from the DRM - being located too close. Its worse on the car radio so I use Radio Australia there. But they dont seem to do DRM to compare.

I've updated the Blog with my last AM stereo vs. DRM tests, also plagued by some intermittent transmitted noise - which turned out to be a faulty 24v switchmode plugpack I was using for the carrier generator.

http://radioalchem.blogspot.co.nz/20...g-pattern.html
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Old 22-06-2015, 20:29   #33
tpreitzel
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Quote:
Originally Posted by Aetheradio
good results. Do you have any comparison recordings of RNZI when they broadcast DRM and AM simultaneously using their same power (PEP capability wise ) transmitters? I can always get a fair AM signal but rarely get any audio from the DRM - being located too close. Its worse on the car radio so I use Radio Australia there. But they dont seem to do DRM to compare.

Not at the moment since I'm living in a basement apartment. Other members of this forum might, though.

Quote:
Originally Posted by Aetheradio

I've updated the Blog with my last AM stereo vs. DRM tests, also plagued by some intermittent transmitted noise - which turned out to be a faulty 24v switchmode plugpack I was using for the carrier generator.

http://radioalchem.blogspot.co.nz/20...g-pattern.html

Thanks.

I've ordered a hum eliminator in an attempt to kill the hum on my AM stereo broadcasts. When I do, I'll post some files comparing reception of AM stereo and DRM at very low power levels. I'm pretty sure that AM stereo will only work acceptably at very short distances with such low power. As it is, I had to increase the RF output from the ASMAX-1 transmitter significantly in an attempt to match the range of the DRMAX-1 transmitter. AM stereo sounds great at short range with my Meduci MW-2. Since the Meduci MW-2 isn't a very sensitive receiver, I lose the AM stereo signal beyond ~ 50 feet from the antenna. I'm currently looking for a more sensitive AM stereo receiver for testing my ASMAX-1 transmitter, but I suspect a robust DRM transmission will be superior in nearly every way at such low power levels.
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Old 27-08-2015, 21:48   #34
tpreitzel
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If the current geomagnetic storms in the northern hemisphere are an example, only the Vatican's robust transmissions to the HFCC 2015 conference will prove remotely reliable over the week. Hopefully, attendees at the HFCC conference will finally get the same memo that the Vatican received years ago, i.e. use a MSC of 16 QAM on shortwave.
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Old 28-08-2015, 13:12   #35
PhilipOneL
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Quote:
Originally Posted by tpreitzel
If the current geomagnetic storms in the northern hemisphere are an example, only the Vatican's robust transmissions to the HFCC 2015 conference will prove remotely reliable over the week.

Yesterday, Thurs 28/8/15, I caught the Vatican's DRM b/c on 11890kHz 2230 -2300 UTC. I don't know whether they were aiming towards me (in eastern Newfoundland, Canada), but their power (250 kW) probably sent it in all directions. I'm listening right now to the recording I made on the MR27024 (with an outdoor eight-metre wire aligned W-E). The signal was best around 2240 with very close to 100% audio decoding for five or six minutes. But by 2252 it had deteriorated substantially with only about 15% audio decoding, and by 2250 there was no apparent signal at all.
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Old 28-08-2015, 22:22   #36
tpreitzel
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Quote:
Originally Posted by PhilipOneL
Yesterday, Thurs 28/8/15, I caught the Vatican's DRM b/c on 11890kHz 2230 -2300 UTC. I don't know whether they were aiming towards me (in eastern Newfoundland, Canada), but their power (250 kW) probably sent it in all directions. I'm listening right now to the recording I made on the MR27024 (with an outdoor eight-metre wire aligned W-E). The signal was best around 2240 with very close to 100% audio decoding for five or six minutes. But by 2252 it had deteriorated substantially with only about 15% audio decoding, and by 2250 there was no apparent signal at all.

You were listening off the reverse lobe of the beam. The stated power is likely the analog equivalent. The Vatican is probably using ~ 125 kW in the digital mode. Furthermore, the ionosphere has been very unstable (auroral effects at higher latitudes as well) over the past few days so your reception off the reverse lobe is proof of the Vatican's wise and robust configuration.

Last edited by tpreitzel : 28-08-2015 at 22:31.
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Old 15-06-2016, 21:51   #37
tpreitzel
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I've included a picture of my antenna system. It's a product of some imagination and experience. Personally, I don't like clutter, but I need to do certain things. I constantly strive to balance time, money, and space. We can literally move our entire household with a bicycle and a trailer if needed.

I only wish manufacturers were as considerate in their designs of equipment. Although the wideband magnetic loop is an excellent concept, it's currently a bit too expensive. The RF PRO-1B is built like a tank and performs extremely well. The outdoor UHF/VHF antenna is made by 1byOne and can be purchased from Amazon. It's fairly well made for its low price and surprisingly performs above average. but don't expect great performance. The 1byOne will pull in ATSC stations indoor from about 10 miles away. Before attaching the 1ByOne, I received about 6 listenable FM stations at night. After attaching the 1ByOne, the number jumped to more than 40 listenable stations. In this picture, the VHF/UHF antenna is obviously not connected.

You'll have to decide where your priorities lie, but radio is a tool for me, not an end in itself. Hopefully, the picture will give new listeners some help in planning their systems. One doesn't need wires and equipment everywhere. Good luck.


Palm Springs commercial photography
http://www.webfilehost.com/?mode=viewupload&id=3149639

Last edited by tpreitzel : 15-06-2016 at 22:32.
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Old 06-07-2016, 19:35   #38
tpreitzel
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Now the real "fun" begins ...

After listening to the constant commercial breaks in some shortwave broadcasts, I've decided to rant a bit about the subject. For example, the Powerhour on the Genesis Communication Network (GCN) has nearly constant commercial breaks which is aggravating over an extended period, e.g. 30 minutes. Although the host announces the upcoming breaks, it's still annoying to mute or retune every 5 minutes or so.

Here's a suggestion for these broadcasters. Limit commercial breaks to a MAXIMUM of 15 minutes per hour, e.g. five 3-minute breaks per hour. If a broadcaster can't fund their production by limiting commercials to 15 minutes per hour, then seek additional funding mechanisms or stop broadcasting altogether. You're currently annoying listeners to death. Here's another suggestion... Use some of your resources (are you listening, Alex Jones?), to fund the manufacture of multimedia DRM radios and encourage GCN or WWCR to install DRM transmitters for their capability of transmitting advertising data concomitantly with the audio which should mitigate the aforementioned problem.

Last edited by tpreitzel : 07-07-2016 at 18:33.
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Old 24-02-2017, 20:15   #39
tpreitzel
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Thanks to Thomas over at SWLing Post, here's a potentially viable alternative to more expensive magnetic loops. If the AM band, bands if you prefer, is to remain viable, magnetic loops will probably play a major role so this development is important. Competition breeds quality while reducing cost, major factors in increasing acceptance by the masses.

http://swling.com/blog/2017/02/the-w...-loop-antenna/
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Old 27-05-2017, 21:50   #40
tpreitzel
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While listening to a comment by Ray Robinson of KVOH that he wasn't necessary wedded to shortwave, a flash of inspiration appeared in my mind.

Although I haven't read about this idea elsewhere, I'm fairly sure that this possibility has been discussed previously by other people.

Can the Creative Commons license be extended to include distribution of content solely via shortwave? In other words, create a license for content that is only legally distributed via shortwave frequencies. Maybe, restricting distribution for open content via shortwave will help sustain shortwave's viability.

PS I haven't checked the Creative Commons licenses for quite awhile.
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Old 29-05-2017, 00:45   #41
Aetheradio
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been thinking of a similar question for part 15 (USA) and LPFM (NZ) broadcast where for me the licence is free 1 watt of FM with antenna restrictions - there are small one man stations in most places

most of these pay a fee around $200 to a copyright consortium per year plus their costs of sourcing the material

so if I use a free stream such as iHeart or Radionomy as the source the royalties are already covered. Or is this different to a home user streaming same content via video sender / WiFi / Bluetooth to speakers around the property?


Quote:
Originally Posted by tpreitzel
While listening to a comment by Ray Robinson of KVOH that he wasn't necessary wedded to shortwave, a flash of inspiration appeared in my mind.

Although I haven't read about this idea elsewhere, I'm fairly sure that this possibility has been discussed previously by other people.

Can the Creative Commons license be extended to include distribution of content solely via shortwave? In other words, create a license for content that is only legally distributed via shortwave frequencies. Maybe, restricting distribution for open content via shortwave will help sustain shortwave's viability.

PS I haven't checked the Creative Commons licenses for quite awhile.
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Old 29-05-2017, 00:45   #42
Aetheradio
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PS I haven't checked the Creative Commons licenses for quite awhile.[/quote]

Last edited by Aetheradio : 29-05-2017 at 00:49. Reason: double post
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Old 29-05-2017, 01:12   #43
tpreitzel
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If such a license doesn't already exist, CAREFUL addition of one to the Creative Commons series should encourage use of the shortwave bands. True believers in the shortwave medium would probably desire such a license. * Done properly, fair use standards in the USA would remain effective so content under such a license could be referenced and discussed elsewhere. With the advent of DRM for broadcasting data, such a license would be timely, I think.

* (I am for previously stated reasons as I will absolutely no longer use the Spynet for anything other than trivial matters). I believe in SETTING the appropriate example by using a flexible and anonymous platform instead of merely following the crowd over a cliff into the Spynet's grid. The smarter elements of the crowd will stop at the edge of the cliff and follow a safer and more secure path. It'll take some time, though.

Last edited by tpreitzel : 29-05-2017 at 01:18.
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Old 02-09-2017, 22:39   #44
tpreitzel
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The DRM Consortium needs to adopt a creative attitude of enticing their members to control their clients' configurations. After all, selling DRM transmitters is only part of promoting DRM.

For example, except for Diveemo, forbid the use of 64 QAM modulation on the HF bands. For Diveemo (if ever standardized), limit targets to less than 2000 miles and MSCs of 64 QAM. For both digital AUDIO and Diveemo on the shortwave bands, short range targets of less than 2000 miles should also use relatively low power with steeper T/O angles and frequencies below 5.1 MHz (60m) or above 17.5 MHz (16m). With the xHE-AAC codec, digital audio on the HF bands doesn't need the bandwidth of Diveemo so an outright BAN of MSCs of 64 QAM should be part of the DRM standard for digital AUDIO transmissions on HF. Unfortunately, DRM SW broadcasters don't seem to have the required discipline to circumvent such a ban.

Last edited by tpreitzel : 03-09-2017 at 00:44.
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Old 04-09-2017, 07:44   #45
F1BJB
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Quote:
Originally Posted by tpreitzel
forbid the use of 64 QAM modulation on the HF bands.
HI
I don't agree that forbidding anything will promote DRM.
On the contrary dynamic changing of modes and frequency according to
target,content and propagation should be promoted.
It will help detecting receivers with too limited features.
Feedback from listeners should allow broadcasters to choose the best mode.
Laurent
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