Sorry Mr Mal
I used to work in the satellite industry - designing and building them. Both systems design and hardware design - so just ever so slightly familiar with them. Biggest claim to fame is probably my designs going into the Inmarsat 3 IF Processor and beam switching matrix. The network that routed uplink signals to spot beams based on frequency , with banks of SAW filters and programmable synthesizers doing the routing. And did the same on the return link. (All pre-DSP)
Hence little interest in most amateur satellite ops - although the ease of use for this latest one does have a certain appeal for some more out of the normal ideas using weak signal datamodes.
Bu this is the LF group so is really OT
Not out of date as you suggest. I have a couple of Humax digital boxes for
my Freesat TV reception also I can receive AO100 on my 1.2 metre dish feeding
the LNB output to a RTL dongle and computer with the appropriate software. I
also have a hi spec multi mode scanner covering the desired
frequencies.
Some high spec satellite receivers currently available provide the option
of Digital or Analogue reception.
I do also have an old analogue satellite RX which has manual tuning and two
IF outputs suitable for add on devices or spectrum display.
I have a selection of HP mixers, low pass filters, and oscillator modules
all in the Ghz frequency range that i could use for the 2.4 Ghz uplink and a
1.8metre prime focus dish.
I have an abundance of equipment available for all occasions.
I am well ahead of you with the knowledge and equipment required to put a
satellite communications system together.
I have been communicating via satellites both commercially and
amateur since the OSCAR 6 era and was the only station to communicate via AO6
between HONGKONG and MELBOURNE AUSTRALIA on CW right on the edge of the
satellite footprint with only a few seconds to make the QSO.
YOU ARE TALKING A LOT OF RUBBISH AS USUAL -------------THE PROVERBIAL
ALLIGATOR
DE VS6HI/G3KEV
Sent: Wednesday, March 06, 2019 2:27 PM
Subject: Re: Not LF: Opera via QO-100
You're a bit out of
date with sat box info - no one uses analogue ones any more with AFC .
It's all digital now.
To receive Eshail most
people use somehting like an RTL Dongle or Airspy SDR directly set
to receive at 739MHz, which is the typical LNB output for the sat
downlink.
You need a proper PLL
LNB to get the stability needed for the narrowband transponder - eg
Octogon. ANd ideally with its LO locked
Marku
There must be a way to modify a satellite RX to receive the AO 100. The
SAT BOX would have AFC built in to avoid LNB drift in normal use.
One method would be to set up the RX box to analogue reception and tune
across the base band, another to tap off the IF 480 Mhz and tune across the IF
with a 70cms amateur RX or SDR dongle and computer
Maybe someone has tried a similar method
73 de mal/g3kevr
Sent: Sunday, March 03, 2019 4:51 PM
Subject: Re: Not LF: Opera via QO-100
Hi
Mal, my 2.4 GHz TX is fairly improvised and may
not be easy to reproduce... I've extracted the LO from an old Sat-TV receiver,
followed by a small Minicircuit amplifier and a 60 cm dish indoors. The PLL
consists of the 1/64 prescaler output fed to a CD4030 XOR phase comparator,
along with a 18.75082 MHz Rubidium-controlled reference. There are surely much better ways to generate a decent 13 cm
signal. PA1SDB mentioned that he uses an Adalm-Pluto SDR from Analog
Devices. You might be able to pick us up on the web-sdr,
using 10489603.5 kHz USB dial, and Opera SW set to Op-05 speed by selecting
e.g. the 1296 MHz band. Yes we could try a crossband contact, but not today.
To count as a valid QSO, we'd probably also need to set up our own receivers,
both for 10.5 GHz and 472 kHz. Best 73, Markus -----Ursprüngliche Mitteilung----- Von: mal hamilton
< [email protected]> An: rsgb_lf_group
< [email protected]> Verschickt:
So, 3. Mrz 2019 16:24 Betreff: Re: Not LF: Opera via QO-100
Markus
How about a XBAND qso AO100/MF on CW
You TX via satellite to me and I tx on 472.5 Khz CW
73 de mal/g3kev
Sent: Sunday, March 03, 2019 1:44 PM
Subject: Not LF: Opera via QO-100
Listening
to the below-mentioned Goonhilly web-sdr, I noticed an interrupted carrier on
10489.605 MHz, which turned out to be 10 mW Opera-2 and Opera-05 transmissions
from PA1SDB. Peter has been well known in the LF group for running a
VLF-Grabber in Appingedam. During the last week,
I had managed to built a rudimentary but stable 2.4 GHz CW transmitter,
allowing me to add in another Opera signal on Es'hail-2. Anyone else to join
in? Best 73, Markus (DF6NM) -----Ursprüngliche Mitteilung----- Von: VIGILANT Luis Fernández < [email protected]> An: [email protected] < [email protected]> Verschickt:
So, 17. Feb. 2019 22:21 Betreff: LF: MF/LF chat over QA-100
Geostationary Satellite ?
Hi
All
May be someone has the equipment and is in the footprint of Es'Hail-2,
formely AMSAT QA-100 satellite?
Nice place for chats working as an HF band permanently open and with
outstanding sensibility
Anybody (appart from David, G0MRF) interested in joining an MF/LF/VLF
chat ?
You need just an SSB rig at 144 or 432, an upconverter to 2.4GHz and a
WiFi PA and antenna and you are in
For Rx you can even use the WebSDR at Goonhilly
Unfortunately the footprint of the
satellite do not cover America (only the extreme East of Brazil)
nor Australia (reaching up to thailand).
But sites like Reunion are in the footprint
73 de Luis
EA5DOM
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