Transmissão
experimental da CVC em DRM nos 17640 kHz. A decodificação
foi prejudicada devido emissão analógica da BBC co-channel
desde Ascencion com 250 kW rumo 114 graus, o sul da África.
No início o sinal da BBC era fraco mas foi aumentando no
decorrer do tempo a ponto de se entender mais informações
do sinal analógico do que o digital. No entanto pode ter
sido alguma particularidade da minha antena, com melhor desempenho
para outra região que não o Chile. Ficou claro que
para cada momento de redução do SNR da CVC, aumentava
da BBC e vice-versa.
Logo
abaxio imagens dos momentos que as portadoras DRM prevaleceram sobre
o analógico, embora a decodificação plena permanecesse
prejudicada (horários locais):
Veja
acima que o analógico era forte, mas o DRM conseguiu passar a informação.
Agora
alguns momentos nos quais o analógico foi mais presente que o digital:
Aqui
os primeiros 15 minutos de captação. A quantidade
total de decodificação DRM durante o período
dos testes não foi alta, comparando com antigos testes bem
sucedidos da CVC.:
A
seguir a imagem do espectro ao redor de 17640 kHz, com as demais emissões
analógicas da faixa. Neste momento havia uma queda do sinal DRM
e era possível ver a modulação da BBC entre as portadoras
DRM.
Entre
1455 e 1505 Z foram encontradas as seguintes emissões:
kHz
Station
Language
kW
QTF
QTH
ITU
Report
Informations
17550
R.
Cairo
Pashtu
250
70
Abu
Zaabal
EGY
14431
vy
weak, S5~S7
17555
Family
R.
Spanish
100
160
Okechobee
USA
34432
17560
Unid
--
--
--
--
--
vy
weak
only
carrier view, s/off 1500
17570
Unid
--
--
--
--
--
vy
weak
only
carrier
17580
Family
R.
Bengali
500
90
Wertachtal
D
weak
s/off
15:59:05
17580
Family
R.
English
250
114
Ascension
ASC
55555
S9,
s/on, beautiful opereta EE
17595
R.
Exterior de España
Spanish
350
302
Noblejas
E
12211
17605
Adventist
World R.
Afar
300
145
Moosbrunn
AUT
vy
weak
s/off
14:58:37
17615
R.
Riyadh (tent)
Arabian
500
190
Riyadh
ARS
33343
strong
but weak audio
17620
R.
France Int.
French
500
185
Issouduin
F
vy
weak
17630
China
R. Int.
English
100
85
Bamako
MLI
33332
s/on
1500, before only carrier
17640
CVC
Spanish
?
?
Santiago
CHL
17
dB
DRM
to B
17640
BBC
English
250
114
Ascension
ASC
33343
Focus
in Africa
17660
R.
Riyadh
French
500
270
Riyadh
ARS
55555
Great
traditional AA mx
17680
CVC
Spanish
100
?
Santiago
CHL
32222
mx
17715
R.
Exterior de España
Spanish
350
230
Noblejas
E
54444
before
14:56 only carrier, clear modulation
17725
La
Voix de l´Afrique
French
500
180
Sabrata
LBY
23232
YL/OM,
ID 14:58
Apesar
da baixa decodificação, foi um bom teste sobre ocupação
espectral adversa para minhas condições de recepção.
Uma estação digital, mesmo sulamericana, pode ter
o desempenho comprometido devido outra estação no
mesmo canal, mesmo que analógica, se ela estiver com alta
potência nas proximidades do continente, mesmo se sua transmissão
não for direcionada para o mesmo destino da digital.
Outro
ponto curioso foi escutar o programa "Focus in Africa" da
BBC, uma tradicional, popular e importantíssima fonte de informação
e expressão em Ondas Curtas.
August, 31; 2010 (Part C: DW)
Transmitter:
Radio Deutche Welle, Sines, Portugal Antenna: "cortina de 8 dipolos" Power: 90 kW Azimuth: 220 degrees Special Target: MOMAG Congress, Vilha Velha, ES, Brazil Freq: 21740 kHz Time: 1300 ~1600 Z
Receiver: Jundiaí,
SP, Brazil. Equip + Softwares: RX-320 + TTRX + Dream. Antennas: Half-wave dipoles for 40m, 20m, random wire,
whip, active antenna Degen 31MS
(Video)
Finally a new stereo emission
on Short Waves to Brazil. It´s quite weird all argument on the quality
of digital audio (that is true) but stay offering the mono version!
The programms also helps
with pop music and comments abt Autobahn, Kraftvert,
and beautiful pieces of classical music.
Here an audio
emitted with 17.38 kbps EEP AAC+ Stereo, converted to WMA 44,1 kHz 96
kbps on the notebook, to 16 bits WAV Stereo as final version of the recording
(02:00 min, 21.640 KB).
Check the other paramethers
screen copied from my old version of Dream:
By the following graphics
you can see that the reception had a lot of losts but as the time goes
on the signal became more stable, confirming the propagation forecast.
21 MHz was not the better choice even according DW engineering, but since
we are in experimental field, these technical variables are acceptable
even for indicate the failure of the scked (that was not fully the case).
The fading process was interesting:
in less that 1 minute the SNR reduces from 15 dB to 11 db! Sometimes the
40 meters band dipole seems provided higher gain but also followed by
more noise (so lower SNR).
Here you can see a comparative
of different kinds of antennas on the reception side, first with the 20
meters band dipole (named "Dip 20m"), then 40 meters band dipole
("Dip 40m"), an active antenna loop by Degen ("Active"),
one long audio cable extended in my house just to see if a not really
dedicated system could be usefull ("Cable"), a solid cooper
wire stand on the soil ("wire"), the same wire plugged on a
passive preselector grounded ("Wire + gnd"), and a simple internal
whip ("Whip"). The external dipoles promoted
far better reception. Click on the image for full view of the graphic:
August, 31; 2010 (Part B: RNW
on two freq)
Transmitter:
Radio Nederland, Bonaire, Netherland Antilles Power: 100 kW RMS Special Target: MOMAG Congress, Vilha Velha, ES, Brazil
Freq A: 15745 kHz Time:
1100 ~ 1300 Z
Freq B: 17525 Time: 1300 ~ 1500 Z
Receiver: Jundiaí,
SP, Brazil. Equip + Softwares: RX-320 + TTRX + Dream. Antennas: Half-wave dipoles for 40m, 20m, random wire,
whip, active antenna Degen 31MS
We had a VERY stable emission
of RNW from Bonaire on 15 MHz peaking 19 dB SNR, with very good use of
the specifications texts told us the correct locations fo the emitter
("Bonaire, Antilhas Holandesas" in portuguese!) and the destiny
(Vilha Velha), despite ID still carrying the standart "NL" of
The Netherlands.
It was indicated MM service
with 3,96 kbps but they did not really offered. Audio with SS news covering
the Mina San José Chile , Resenha abt tecnología, Resumem
de la Prensa Européia. Clear but poor audio quality since the generation
came from external interviews and talks, so the problem was not on the
transmission mode, but on the origin of the audio recorded. Talk radios
style and journalistic programms
will should improve their links and mics If really want full apply digital
audio quality.
Here
an example of the audio 17,38 kbps EEP AAC+ Mono > WMA 44,1 kHz
96 kbps Stereo
(WMA, 06:00 min, 4140 KB)
The images below represents
the second service of the day now on 17 MHz, still very loud but with
quickly undecodes, not able to denegrate the overall quality. The SNR
was 17 ~ 14,4 dB, with the decays around 1334 Z due low MSC MER. See the
interesting unusual horizontal lines on the waterfall spectrum like short
events of WB ocupation inside the fading "spaces". Programms
in SS news with very interesting interview about sociology and history.
(Video)
On the final 8 minutes of transmission
we used different types of antennas. A: Internal whip; B: single wire
(full extended to FAC green, SDC red and partial ID); C: audio cable,
D: Active loop (very weak with FAC red and SDC red at best), E: 40 meters
band dipole, F: 20 meters band dipole.
The external antennas provided the true decodes.
Whip and the active loop near the non reflective
wall structure of papers and books :)
August, 31; 2010 (Part A: RFI)
Transmitter:
TDF/RFI DRM Montsinery, French Guiana Power: 100 kW RMS Antenna: Curtain
42 or 43 Azimuth: 165 degrees Special Target: MOMAG Congress, Vilha Velha, ES, Brazil Freq: 17315 kHz Time:
1100 ~ 1600 Z
Receiver: Jundiaí,
SP, Brazil. Equip + Softwares: RX-320 + Dream. Antennas: Half-wave dipoles for 40m, 20m, random wire,
whip, active antenna Degen 31MS
(Video)
Another good listening of
RFI. We have more undecodes relative to yesterday´s later listening
but still an usefull service. Audio with SS news abt Iraq, Cachemira,
St. Barthelemy, Palestina, Mexico, Venezuela, Puerto Rico, Tema del Día,
long Marine info in FF (Météo) and musics. Around 1525 Z
an audio piece about "pelegrinage" to Santiago de Compostela,
when RFI speaks again in portuguese to Brazil on radio waves! Indicated
Zero Data service but in fact they still offered the same political images
of the past emission.
Here a part
of the audio transmitted with 17,00 kbps EEP AAC+ Mono > WMA WMA
44,1 kHz 96 kbps Stereo
(WMA, 08:00 min, 5800 KB)
August,
30, 2010 (Part B, DRM signals after first MOMAG schedulle)
All
India Radio from Khampur 50 kW to Europe, well identified with
two audio services but none decoded due missing MSC data. Anyway it is
the most usefull service to provide basic text informations and status,
and all coming from Asia!
The
first waterfall was at 2012 , the better time for reception.
The following was at 2130 with huge decrease of signal and background
local noise.
Spectrum
of Disco Palace 15755 kHz from Bonaire 100 kW to USA.
Noted the carrier only:
Spectrum
of Voice of Russia 9880 kHz from Bolshakovo 60 kW with
lot of noise just over the OFDM carriers:
Spectrum
of Radio Romenia International from Galbeni 90 kW to Europe with severe
co-ch analogical signal of Radio China International from Urumqi 500 kW
to 270 degrees, 2019 Z.
After 2024 Z noted with a lot of background local noise.
August, 30; 2010 (Part A)
Transmitter:
TDF/RFI DRM Montsinery, French Guiana Power: 100 kW RMS Antenna: Toucan
1 Azimuth:
165 degrees Special Target: MOMAG Congress, Vilha Velha, ES, Brazil Freq: 17315 kHz Time:
1100 ~ 1600 Z
Receiver: Jundiaí,
SP, Brazil. Equip + Softwares: RX-320 + TTRX+ Dream. Antennas: Half-wave dipoles for 40m, 20m, random wire,
whip, active antenna Degen 31MS
TDF
label transmitting RFI Musique audio service, much better than EBC institutional
programms past used on TDF tests to Brazil.
Here
some
musics transmited with 17,00 kbps EEP AAC+ Mono converted to WMA 96
kbps 44,1 kHz Stereo
on the recording site. (WMA, 07:00 min, 5000 KB)
Now
some
space for content comments: The TDF multimedia image feed remains
the same of every test to Brazil: photos of TDF installation, members,
logos and Brazilian federal politicians photos. Nothing to say in
the past, but now Brazil is under a national election process. The
Brazilian media is under narrow rules of election coverage ideally
to ensure more equanimal exposion of the candidates. When RFI/TDF
broadcast especially to Brazil the image of only one of the candidates
to president (that was minister during the past tests periods),
It is not fair. For sure TDF/RFI did not supported any political
party, but despite it was only a technical test (watched by few
views) and came from French Guyana (not under Brazilian laws), It
was also the first digital radio election "infringement"
case, even before the possible digital radio technical model adoption
in Brazil. International broadcasters must pay more attention on
these details on future emissions. It´s not only a technical
subject, but ethics on international radio journalism respecting
local community calendar and practices at least when the target
is a democratic country, the case of Brazil. The image feed neither
is an auxiliary service only, social communication content is obviously
involved. Images are relevant informations even on the digital radio
and deserve careful attention from the producers, broadcasters,
regulators and listeners.
See
the general data and DRM specifications at 1855 Z with very good spectral
presence.
Incredible
stable signal of RFI/TDF from 1920 ~ 1950 around 20 dB SNR
with very brief no-decoded audio periods. Click on the image for wider
graphic:
Check
also the other paramethers by Dream:
June, 01, 2010 > Radio Exterior
de España from Costa Rica
DRM carrier bus of Radio
Exterior de España transmitting from Costa Rica to North America.
On left side a chinese
analogical emission.
Just the partial ID
informations. For each 5 minutes of reception, 2 of then were low signals
read on
SNR 3 ~ 6 dB, not able
for full FAC and digital audio transfer.
Three reasons for low
signals: REE emissions were devoted to North America, bad propagation
conditions and
high local electrical
noise level. On the image one of these bad sources appearing on the spectra.
Around 0300 Z, REE back
to analogical status with musics and time marks, SINPO 21122.
May, 09, 2010 > Radio Cultura
of Sao Paulo, AIR Khampur India, CVC Santiago Chile, RNZI New Zealand
ID, instantaneous data
information and spectrum of Radio Cultura de Sao Paulo
now in 26040 kHz at 2130 Z. No audio decoded.
Meanwhile CVC of Santiago
17640 kHz with musics at 1920 Z.
BBC/DW from Sines (POR)
was also strong with segments of audio decoded,
classical music and interviews at 2050 Z.
All India Radio 9950
kHz with good presence at least for the FAC and SDC informations arounf
2000 Z.
SNR(blue line) and audio
decoded (black bars) at 1957, 2043, 2058 and 2116 Z (left to right).
See the short audio frames in the middle imagens and SNR decay on later
time.
Here the possible explanation of the
beahaviour due sunset with the abrupt decrease of LUF and
smooth decrease of MUF starting at 2000 Z. 10 MHz became above LUF and
below MUF, but only for
some time when MUF also decrese below 10 MHz. It is represented in practical
terms on the peaks of the grafics above. (SFI=71, SSN=11, A=4, K=1,
NOAA 1806 Z 09 may 2010)
Radio New Zealand International
11675 kHz produced these weak carriers bus on left side
of the screen at 2115 Z. No data or audio detected.
Radio Romenia International
DRM shadow on 7295 kHz at 2010 Z under several analogical side and co-channels.
Beggining of data decoding
but not far from it.
May, 08; 2010 > Radio Cultura
of Sao Paulo, CVC Santiago Chile, BBC/DW Sines Portugal
First indication of
Radio Cultura de Sao Paulo at 1717 Z on 26045 kHz. (TU PP5AZF for the
news!)
All data received at
1919 Z.
Spectrum of Radio Cultura,
on the lower side weaker signals with 40 meters dipole and
on upper side stronger carriers with 20 meters dipole.
Copy of instantaneous
data and DRM mode indicator.
Usuall status of SDC
ready while MSC and interesting FAC not decoded.
SNR and doppler closing
1915 Z.
CVC Chile was also on
the band with good signal and full decoded data
and audio to Brazil on 17640 kHz 1822 Z.
SNR and audio decode
at 1801 Z (left) and increasing at 1745 Z (right).
Signal levels of Radio
Cultura Sao Paulo Brazil (left blue line) as received inside the 26 MHz
skip zone
versus BBC/DW Sines Portugal (right blue line) on 15 MHz inside far F2
affected zone around 1745 Z.
December, 16, 2009
Transmitter:
TDF DRM Montsinery, French Guyana. Target: Tests and demonstrations to Brazil, changing
on the power output. Programm: Institutional from EBC - Empresa Brasileira
de Comunicação (Brazilian fed gov). Freq: 17875 kHz. Original Sched: 08 to 17 december 2009.
Reading at 1628 Z, just
after the midday, with lower SNR at start point but still decoding the
audio and very interesting stable delay during the first minutes with
clear flat doppler curve. On the following graphics the beggining of the
listening (left side) and the evolution.
Compare now with the 1745
Z shots:
Here the heavy lightnings
around the listening post on the final time of the sched:
Lighting (horizontal line)
on DRM signal, but no lost of the digital audio:
Lightning map on the time
produced by ELAT
- INPE.
December, 15; 2009
Informations of AIR, RCI, TDF/EBC
and CVC.
All India Radio, 9950 kHz,
2147 Z:
Noted the different pattern
of the carriers received due propagation effects:
AIR out. Horizontal lines
are peaks from bad electrical fences:
Now Radio Canada International
from USA 9800 kHz, 2200 Z:
BW of Radio China 11685
kHz analogical AM SW signal and Radio Canada 9800 kHz DRM 2205 Z:
Comparative of the good
signals of EBC/TDF French Guiana (left) and CVC Chile (right). 1905 Z:
Comparatives during bad
conditions for CVC and good EBC. 1925 Z:
CVC with bad MSC. On the
right side of the FFT the TDF/EBC carriers. 1908 Z:
.
December, 14; 2009
Informations of AIR and DW/BBC.
AIR 2151 Z 9950 kHz analogical
signal on time devoted to digital sched. Same transmitter?
DW/BBC from Sines 3995 kHz
2147 Z, picture of their faint DRM carriers, no data decoded.
December, 13; 2009 (part B)
Transmitter:
All India Radio, Kampur, 50 kW. Target: Europe, daily emissions. Programm: Music, Hindi (only received the basic data) Freq: 9950 kHz.
Only received the basic data aroun
2150 UTC. Videos:
December, 13; 2009 (Part A)
Transmitter:
TDF DRM Montsinery, French Guyana. Target: Tests and demonstrations to Brazil, changing
on the power output. Programm: Institutional from EBC - Empresa Brasileira
de Comunicação (Brazilian fed gov) . Freq: 17875 kHz. Original Sched: 08 to 17 december 2009.
Transmitter:
TDF DRM Montsinery, French Guyana. Target: Tests and demonstrations to São Paulo
and Rio de Janeiro, Brazil. Programm: Institutional from EBC - Empresa Brasileira
de Comunicação (Brazilian fed gov). Freq: 17875 kHz.
Basic informations fo
the TDF emission, unfortunately with low SNR, unable to
full digital decode at the period of my monitoring.
On left, reception level
with 20 meter band dipole and on right with 40 meter band dipole.
Two different moments
of DRM signal with 20 kHz of SDR receiver span and 20 meter band dipole.
Bad compositon of DRM
carriers over that time.
May; 2009
Transmitter:
TDF DRM Montsinery, French Guiana. Target: Congresso Brasileiro da Radiodifusão,
Brasilia - DF, Brazil. Programm: Institutional from EBC - Empresa Brasileira
de Comunicação (Brazilian gov) . Freq: Check schedulle.
"Emission A":
very good digital audio and images received. Just few moments sign/off.
See the images captured by radio:
"Emission B"
had with much better signal quality, FULL reception with non-stop digital
audio and images feed. It was the best DRM´s parameters ever captured
on my location.
Despite the fading, the emitter´s
power or directivity where sufficient to not denegrate the SNR and did not
interrupt the digital reception. Very robust DRM mode for that condition.
Spectrum on 17 MHz with
fading but stable digital:
Now almost perfect on
17 MHz:
The sunday´s emission
on 17 MHz had fails on the carrier, here the sequence:
One of these segments
taked closer on different time mark:
The next image is one
wide compostion of 17 MHz broadcasting band. On the maked points the DRM
transmissions of CVC Christian Voice Chile and TDF French Guiana, both
in portuguese to Brazil!
April, 19; 2009
Transmitter:
TDF/RFI DRM Montsinery, French Guiana. Target: NAB Show Dallas USA. Freq: 17545 kHz.
.
