Showing posts with label ZSJ. Show all posts
Showing posts with label ZSJ. Show all posts

Thursday 17 September 2009

New edition of rfax.pdf HF-FAX guide ... Updated!

Here is the latest (10 September 2009) version of rfax.pdf guide, which is updated. There are less stations listed now, which means that some are no longer transmitting... This is a bit sad...

BTW right now the South Africa ZSJ station has a fair image quality on 18236.10 kHz, USB mode...

Tuesday 16 January 2007

Cape Navel today and... yesterday

The ionosphere is disturbed again, but reception on 18238 kHz today at around (!) 1530z was the best I ever had! The transmission started early at 1523z, and was a "blurred" Surface Analysis chart.

18238 kHz, 1523z 12:00 Surface Analysis


But yesterday... a series of false starts:
  • 1538z: Transmission of a "blurred" Surface Analysis starts.
  • 1549z: Stops! Starts again!
  • 1552z: Starts again! Ends!
  • 1553z: New trial: Header only!
  • 1555z: New attempt, this one finishes normally at 1616z!

Wednesday 10 January 2007

ZSJ Cape Naval again

18 MHz was quieter this morning, but instead of a typical weather chart, I got this one:

18238 kHz, 1033z

Yes, It's only that. I have rotated the image. Also, some image editing magic to correct my decoder's fault of missing sync and adding the final part of the transmission. If you compare the header with my previous images, it's obvious that conditions were better. Cape Naval notoriously continues to transmit early or late, even only the header for a couple of times before transmitting a chart. At least some moments later got some charts:

18238 kHz, 1102z

18238 kHz, 1124z

Conditions stayed good in the afternoon; a "blurred" chart this time:

18238 kHz, 1532z


I like this station because it's so unpredictable. I can't wait sunspot number rise and have even better signals on 18 MHz! I like higher frequencies; they give cleaner and steadier HF-Fax images!

Friday 5 January 2007

Some more HF-Fax images from Cape Naval

I rolled a new "matching transformer" since I have more noise these days and I thought my old one may failed. The new one uses a ferrite toroid from a busted PC motherboard. It seems that the noise wasn't coming from there, something else is happening. At least the new transformer seems to work better on higher frequencies (preliminary result of course!) So here are some more charts from Cape Naval. And you'll see what I mean with "blurred" charts.



18238 kHz, 0730z, 12:00 SURFACE PROGNOSES (PREVIOUS DAY'S RUN)


So this is how a "blurred" one looks like.


18238 kHz, 0803z, ANTARCTIC ICE LIMITS


Note the "UNCLASSIFIED" notice. (Last word in the text box)


18238 kHz, 1029z, 06:00 SURFACE ANALYSIS


Also a blurred one.


18238 kHz, 1100z, 00:00 SURFACE PROGNOSES


Today they were almost exact regarding start time. But still, if the signal is not strong at your location, it's difficult to catch the start, since the phasing sequence is brief (where is Kyodo, with the nice long tuning session?)

Thursday 4 January 2007

New Charts from Cape Naval

11 minutes late! They started at 0741z on 18238 kHz in a hurry! I was ready to tune my receiver to something else, when I heard them rushing to start the transmission! At least there is a 1600 Hz tone idling before the transmission. I still have weak signals so the combination of all these make this station very tricky to catch!

Another thing I forgot to mention: Some charts transmitted blurred, i.e. with lower resolution, like resampling an image to fewer pixels. I don't know if this is intentional, the result is unreadable though.

18238 kHz, 0741z



18238 kHz, 1102z


Now this one started 2 minutes earlier!

Wednesday 3 January 2007

ZSJ Cape Naval, South Africa HF-Fax

A decent chart appeared on my screen this morning, along with a partial RTTY transmission. So far the best frequency for me is 18238 kHz, but I have to operate on batteries to reduce QRN from my PC. Unfortunately there is noise on some frequencies caused from my computer. In the case of Cape Naval transmission, the signal is very weak and I have to run on batteries.

18238 kHz, 0756z

Station's schedule can be found on the South African Weather Service web page.

Two very important things to keep in mind if you decide to hunt this one:
  1. They don't start exactly on time, sometimes 8 minutes earlier or 4 minutes late.
  2. The preamble (tuning) sequence is very, very brief, so your decoder might not catch it.
RTTY transmission excerpt:

A EXTENSPOM OF WINDS BY QUADRANTS (KM):
30 KT NE: 150 SE: 250 SO: 200 NO: 150
50 KT NE: 04)2 SE: 040 SO: 40 NOWJ
A FIRST CLOSED ISO(PRESSURE AVEAGOCDIAM): 1008 HPA /400 KM A
VERTICALPXENSION OF CYCLONE CIRCULATION: DEEP

B FORECASTS:
12H: 2007/01/83 14 UTC: 11.0S/47.6E, MINDOTVKT, OVERLAND.
24P: 2007
84 0/75:: 21.6S/47.0EN MAX WIND=030KT, OVERLAND.
36H: 2) 01/04 18 UTCTI WWMTS/46.:MAX WIND=020KT, DISSIPATING.
48H: 2007/01/05 06 UTC: 23.4S/46.7E, MAX WIND=020KT, DISSIPATINGBOTHER INFORMATI
ONS:
CLOVIS IS MAKING LADFALL NORTH OF N
ASRCF
IT SHOULD RAPIDLY WEAKEN OC LAND AND DIZOGANIZE DURING OPE
NEXT WWR TO 48 HOATXHREPTISITUATION AT 030600 C
HIGH 1026 HVAH33F8W HIGHEUR HPA 37S49ELFOTI HPE 57S15W LOW 1010 HPA 4S DE LMW
994 HPA 57S3
S
LOW 1008 PA 22S40E SEVERE TROP
STORM(CLOVIS
OIT HPA 20.5S /
48.7E

1/ COLD FRONT:'67?2-8EEKW 45S19W 50S10W 55SUPLW
2. COLD FRONT: 35S15E UFWS28/3)45S38E 50STFTTS43E 58S38E

AREA FORECAST
ASCENSION (06S/15S 00E/20W)
BSE PHLQQ TO 20.
VIS : GOOD.

ANGOLA CKPYS.19=': 00E/ COAST)
WIND : O SW 05 TO 10 BUT SE 10 TO 25 .8, 5'3 23'5.
VCDN : GOOD.
ST HELENA (15XEPS, 00E/20W)
WIND C SE TO E 10 TO 20
VIS : GOOD.

TRADES (15S/30S, 00E/WEST COAST)
WIND : S TO CE 10 TO 20.
VIS : GOOD.
SEA STATE: 3.0ZWITH SW SWELL.

TRISTAN (30S/'(/(),001)26
WIND :8VARIABLPHK TO 10 IN THE EXTREME NORTH, OTHERWISE NW
20 TO 30 BECOMING SW 15 TO 20 IN THE
H-WEST
TOMORROW MORNING.
VIS N IGCOR IN RAIN AND SHOWERS IN THE SOUTH.
SEA STATE: 3.5 TO 4.5M I THE SUTHBN SW SWELL.

CAPE WEST (30S/40/''0+/20E)
WIND :6859 '3,059 20 IN THE NORTH, OTHERWISE NW 20 9
TO 30.
VIS TOD BUH POOR IN RAIN AND SHOWERS IN THE SOUTOPV
SELATE: 2.5 TO 3.5MNVNHHHE SOUTH-WEST, SW SWELLRBZUI EAST (32.5S/40S,28EBBPE)


WIND : E TO NE QT T
IGIN THE EXTREME NORTH, OTHERWISE NW
I H959 2''= '2 15 TO 2',45'023'5)74.
VIS NPGOOD BUT POOR IN RAIN IN THE EXTCHCBT.
SEU JR ZMT TO 3.0M IC GDNEAST, WITH SW ELL.


The decoding is not error-free due to low signal strength.

Other frequencies? Well, I haven't confirmed any other frequencies. I guess 7508 kHz is valid since I have a trace of a Fax transmission yesterday at 2245z.

Conditions are still disturbed and the frequency (18238 kHz) asks for more sunspots and quiet ionosphere! Hope this will happen soon!