Report from Brazil DRM test

 

It is in Portuguese, but has some great images and a post from Brother Zyg included! Check out the PDF here.

VOACAP plots for Rádio Nacional da Amazônia DRM Test

Brother Zyg has graciously provided us with VOACAP plots for the ongoing test. We are starting here with 20:00 UTC.Thanks Zyg! 

The "High-Frequency Parties" return!

You might remember our previous input on SWBC matters several years back. Now, with this pending application containing potentially "spurious emissions", we have decided to say our piece. We are known as the High-Frequency Parties, consisting of Benn Kobb, Dr. Kim Andrew Elliott and myself, Christopher Rumbaugh.

We're filing an objection with the FCC to an application for International Broadcast Station being proposed in Illinois. Do we want and support DRM? Of Course we do! Do we believe that latency arbitrage in International Shortwave Broadcast Bands is a deleterious intruder? You bet your sweet bippy we do! Read our take here.

Once again, antiquated rules are hindering radio technologies. In this case, latency arbitrage is certainly a reasonable use of radio waves - but it does not belong in-band with International Broadcast stations. International Broadcast bands are global-village shared public resources for the promotion of culture, ideas and mutual understanding - not encrypted financial trading data.

UPDATE 20200708 1830 UTC : Here is an article in Radioworld on the "High-Frequency Parties" objection filing.

Again with the DRM and a "bonus" arbitrage payload

Yet again, another arbitrage shortwave plan, this one from Batavia Illinois.

Brother Zyg says this smells like what we have already seen with WINB and the never-developed Turms Tech project. Brother Benn says "Arbitrage shortwave transmission is not broadcasting as defined in Part 73F for International Broadcast Stations."

Religious investment? I like the TCI wire Log. They can divert that to my acreage!

KTWR DRM schedule update and VOACAP plots

Schedule changes highlighted in yellow:


1026-1056 11995kHz GUAM 90 kW 315° CIRAF 45 Wed

1230-1245 7500kHz GUAM 90 kW 320°CIRAF 45 Thu [ends 3 May]

1026-1056 15200kHz GUAM 90 kW 285°CIRAF 41 Sun

1245-1315 UTC 7500 kHz   TWR GUAM 90 kW 320° CIRAC 45 (Sun) [begins 3 May]


CIRAF Zones

VOACAP plots courtesy of Brother Zyg!

UPDATE: DRMNA EXCLUSIVE - Radio Marti on DRM!

Updates to the Radio Marti DRM broadcasting test:

Frequency is 7345 kHz from 1700-0200 UTC.

Reception reports today came in from Georgia, Florida, Washington, Dominican Republic, and Colombia.

Current testing has it in 64 QAM with Radio Marti on one audio service and VOA on another audio service. The bit rate for VOA is really low.

Depending on reception reports, they may drop to 16 QAM and only run one audio service. Using the xHE-AAC codec means some people cannot decode the audio, but it saves lots of bits! The Gospell and Avion receivers currently available should have no problem with audio decoding.

Brother Zyg also reports:

1. I am receiving the DRM transmission on 7345 kHz here in the Atlanta area even though my shortwave antenna was blown down very recently and is lying on the ground in several pieces!  The Screen ID shows two separate audio streams, Radio Marti and Voice of America.

2. I cannot decode the audio because it is using the latest xHE mode and the Dream software does not have that capability.

3. The KiwiSDR web receivers do have the xHE decoders (DRM extension) and I have listened to the audio on several KiwiSDR receivers in the SE USA.   

Here are Zyg's hour by hour VOACAP plots:

[Gospell display photo from @SWWINB]

Komsomolsk Amur DRM update

Komsomolsk Amur transmitter site in Asiatic Russia now has three frequencies listed on HFCC as of 5 Sep 2019:

11615kHz 2000-1000 UTC 250kW
(may be a typo of 25kW?)

12025kHz 2000-0300 UTC 25kW

15735kHz 0300-1000UTC 25kW. 

Thanks to Brother Zyg of DRMNA and DRMRX for the update.

UPDATED: WINB and DRM

Please find below, Brother Zyg's VOACAP work related to WINB DRM testing (updated with information from Hans about their Rhombic being terminated). 

- DRMNA Admin

WINB reports : 

"We are testing in DRM 15670 kHz M-F 

try between 1100-1700 UTC"

Here is a preliminary view of the WINB 15670 kHz DRM coverage at 1600z for June 2018.  The coverage is for a receiver using only a 6 foot whip antenna.  Higher gain antennas may produce better results.

The WINB Rhombic antenna parameters are taken from the HFCC files.  Although the transmitter has been stated as "being rated for 15 kW", I'm using a conservative estimate of 10 kW DRM power for the plot. From SWL reports the transmitted bit rate has been monitored as being 8.28 kbps, which should help it to be decoded at lower signal levels.

A report in the DRM RX forum indicated that the signal was relatively strong in Newfoundland at this time but with deep fading and then disappeared some minutes later.  This agrees with the plot which shows the listeners location just on the edge of stronger signal coverage.  The propagation does move the stronger signal area eastwards as time progresses.  There were also reports from the UK and France at a little earlier time when the signal would have been at a somewhat higher level in those areas before moving eastwards.

On Friday, I monitored the KiwiSDR web network of receivers at 1600z and found 15670 kHz DRM "waterfall" signals in Houston, Miami (stronger), and Iceland (weak).  I did not encounter any DRM signals in Europe at that time, but Radio France International has a 500 kW broadcast from Issoudun, France, beaming south to Africa on the same frequency and at the same time!  There was also a much weaker, but still noticeable, signal in the Atlanta area (as received on my Kenwood R-1000 receiver and a long wire antenna).

The plot only shows signals that are stronger than S6 (on an S-meter).
Finally this coverage is for "normal" propagation conditions which just happen to have a zero solar sunspot number as we are in the bottom of the 11 year solar cycle.  Conditions have been less than normal in the past few days.


73,
-Zyg

VOACAP for Brasilia test

Hello Cuba and the Caribbean! Looks like even some of CONUS gets this one. Brother Rafael sends details:

"We assembled the pre-amplifier and the final amp is a ham-amplifier
RM-Italy HLA 305. The modulator is USRP/Spark.
Here in Brazil people could hear small audio hiccups in Rio de Janeiro
(about 1000km away) with the antenna beamed to south.
HR 4/4/0.5, 7db of gain, 312 degrees, 150W "

So, none other than Brother Zyg to the rescue with a VOACAP.

I must say, time and time again I am impressed by the International nature of our hobby. In a time of civil wars, refugees and "building walls", I am humbled by the DRM and Shortwave communities. There is HOPE, my friends. I'm tempted to sing Kumbaya, but I will resist.