Re: Not LF: Opera via QO-100

[David Bowman <davidg0mrf@gmail.com>]

Hi Mal

Most of the LNBs designed for HD TV have a PLL for low phase noise. These have 'acceptable' drift for CW and SSB QSOs......Just let them warm up for 10mins before you use them.  (or fit a TCXO instead of the 27 / 25MHz crystal)

No set top box required.  Just small dish + LNB into a dongle.   Trying to get an output directly at 70cms is a bit hit and miss as you are well below the lower 750MHz limit of the LNB.

73

David

On Wed, Mar 6, 2019 at 1:56 PM mal hamilton <g3kevmal@talktalk.net> wrote:

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

 

Fn rom: Markus Vester

Sent: Sunday, March 03, 2019 4:51 PM

To: rsgb_lf_group@blacksheep.org

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 <g3kevmal@talktalk.net>
An: rsgb_lf_group <rsgb_lf_group@blacksheep.org>
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

 

 

From: Markus Vester

Sent: Sunday, March 03, 2019 1:44 PM

To: rsgb_lf_group@blacksheep.org

Cc: pa1sdb@amsat.org

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 <luis@vigilant.es>
An: rsgb_lf_group@blacksheep.org <rsgb_lf_group@blacksheep.org>
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

https://eshail.batc.org.uk/nb/

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