Could VARA HF SSB work via the new Es'Hail 2 Geostationary Ham Satellite ? #WinLink #VARA


KC9SGV
 

Hi All, 
The new Es'Hail 2 Geostationary Ham Satellite is up and being tested before being released for general ham radio operation amongst others.

A narrow band non-inverting (bent pipe) transponder and a wide band 8 MHz transponder for Ham TV applications will be available.

Uplink is 2.4 GHz
Dowlink is 10 Ghz

FM is discouraged, but it looks like many SSB signals could be accommodated on the narrow band general mode feature.

So, my question here is:
Would VARA HF (2.4 KHz wide) work through this exciting and very accessible new geostationary satellite for European hams ?

https://amsat-uk.org/satellites/geosynchronous/eshail-2/

https://eshail.batc.org.uk

KC9SGV


Andrew OBrien
 

Interesting question.  We need one geostationary for North America too !
Andy K3UK 


James Clark
 

Geostationary orbit is about 36000km so the combined delays from packet Tx to packet ack. Rx is about 0.5S. I assume the Tx software expects a virtually instant reply so the delay may cause problems. Have to try it and see.


Siegfried Jackstien
 

when the sat is a real transponder and does not hurt the signal then ANY digital mode should work

i am guessing for low power voice would be freedv the first choice :-)

planned setup for eshail here is a low power sdr plus amp at the dish for uplink ... and for receive a well locked lnb

if one has bigger astra dish then maybe he can mount a dualband feed inside that dish and does not even need a special antenna for eshail

as you know astra and eutelsat (hotbird) are on 19 and 13 degrees east .... and eshail will be on 25-26 degrees east ... so nearly same degres distance to astra as eutelsat has but on the other side ... using this astra dish and mounting a dualband feed besides the astra lnb seems a possible solution (xyl freindly setup hi hi)

with a 1m dish and normal voice (ssb) 10w is enough for the uplink ... so with freedv even a 1w or lower signal should make it  ...

sending tv signals over that 8megs wide transponder is a different story ... a bigger dish (1.8 or 2.4m) ... a bigger amp (100w or more) is needed then ...

i had the idea to mount an uplink and downlink at out ATV repeater site ... so any atv user then can work digital tv over eshail without the need for an own uplink system (but sure not switched on 24/7 so other users also can use eshail) .... THAT would be nice ... television over that sat ... but you just have to send to your local repeater

(also possible to link voice repeaters that way over the narrowband transponder)

but to came back to your question ... i am guessing vara will work ... as any other mode should

dg9bfc sigi


Am 28.11.2018 um 13:02 schrieb KC9SGV:

Hi All, 
The new Es'Hail 2 Geostationary Ham Satellite is up and being tested before being released for general ham radio operation amongst others.

A narrow band non-inverting (bent pipe) transponder and a wide band 8 MHz transponder for Ham TV applications will be available.

Uplink is 2.4 GHz
Dowlink is 10 Ghz

FM is discouraged, but it looks like many SSB signals could be accommodated on the narrow band general mode feature.

So, my question here is:
Would VARA HF (2.4 KHz wide) work through this exciting and very accessible new geostationary satellite for European hams ?

https://amsat-uk.org/satellites/geosynchronous/eshail-2/

https://eshail.batc.org.uk

KC9SGV


Graham
 

Short answer is 'yes'

KB6OIL is,looking at it , 

The modem will automatically
Adjust for the link delay , additional 
Adjustment is available , by the tx delay 
Intended for repeater use ..

73 Graham 
G0nbd





KC9SGV
 

Hi Andy,

10 GHz dongle.
We could start by receiving 10 GHz signals like this....
Then hunt around the Southern sky to see what is out there:

https://amsat-uk.org/2017/04/21/low-cost-10-ghz-ssb-receiver/

http://gm1sxx.blogspot.com/2016/06/a-cheap-10ghz-receive-system.html

Bernie,
KC9SGV


Tom DF5JL
 

Think the latency is too high for ARQ modes.

73 Tom DF5JL

Am 28.11.2018 2:16 nachm. schrieb Andrew OBrien <k3ukandy@...>:

Interesting question.  We need one geostationary for North America too !
Andy K3UK 


Graham
 

Tom , yes that was a design factor , during the Ros hf  mode development  , the time taken for the arq  protocol to execute , would significantly reduce the throughput of the system ,  the ability of the coding , to recover the transmission,  negate the need .

Modes , eg,  amtor  , do have a maximum path  limitation , determined by the system design, back then, the faster the station could change from tx/ rx  determined the maximum range  , latency in the path , would prevent deployment . 

VARA could operate at one block evey day, if that time was defined as the 'delay'  , the delay is minimised to achieve the highest link throughput  , compensating for path conditions .

But taking your point, yes latency has the possibility to reduce the 'rate, however, assuming good s/n , the high volume of data , per  block, will , endeavor to still provide rates much higher than conventional system's

Power budget,  vara  fm  9.6 (replacement ) may prove to be quite efficient ??

73  Graham


KC9SGV
 


KC9SGV
 

Watch the RF exposure !

5W into the 35 dbi dish antenna is 60 ft minimum.

http://hintlink.com/power_density.htm

Correct me, if I am wrong, please.


M5AKA
 

Looks like that calculator is set up for lower frequencies, uncheck the Ground Reflection option, that'll reduce the distance.

1 mW/cm2 figure is for exposure averaged over 30 minutes.

In OET Bulletin 65 the FCC notes "the most restrictive limits occur in the frequency range of 30-300 MHz where whole-body absorption of RF energy by human beings is most efficient. At other frequencies whole-body absorption is less efficient, and, consequently, the MPE limits are less restrictive"

73 Trevor M5AKA


On Friday, 30 November 2018, 18:31:50 GMT, KC9SGV <kc9sgv@...> wrote:


Watch the RF exposure !

5W into the 35 dbi dish antenna is 60 ft minimum.

http://hintlink.com/power_density.htm

Correct me, if I am wrong, please.


Siegfried Jackstien
 

with 1w in my 6 footer i have about a kilowatt in erp ... but i have no fear in standing in front of that dish :-)

dg9bfc sigi


Am 30.11.2018 um 21:10 schrieb AKA via Groups.Io:

Looks like that calculator is set up for lower frequencies, uncheck the Ground Reflection option, that'll reduce the distance.

1 mW/cm2 figure is for exposure averaged over 30 minutes.

In OET Bulletin 65 the FCC notes "the most restrictive limits occur in the frequency range of 30-300 MHz where whole-body absorption of RF energy by human beings is most efficient. At other frequencies whole-body absorption is less efficient, and, consequently, the MPE limits are less restrictive"

73 Trevor M5AKA


On Friday, 30 November 2018, 18:31:50 GMT, KC9SGV <kc9sgv@...> wrote:


Watch the RF exposure !

5W into the 35 dbi dish antenna is 60 ft minimum.

http://hintlink.com/power_density.htm

Correct me, if I am wrong, please.


Siegfried Jackstien
 

hmm ... a 1.8m dish has around 30db gain on 2.4 gig ... (with efficiency of 50% ... with 70% it is more 32 db)

means with 10w you have an erp of 10kw ... shouldnt that be enough??

https://www.everythingrf.com/rf-calculators/parabolic-reflector-antenna-gain

dg9bfc sigi



Am 30.11.2018 um 18:09 schrieb KC9SGV:

Watch the RF exposure !

5W into the 35 dbi dish antenna is 60 ft minimum.

http://hintlink.com/power_density.htm

Correct me, if I am wrong, please.


KC9SGV
 

Available America's Geostationary satellites to receive with a RTL SDR and old LNB.
http://frequencyplansatellites.altervista.org/Beacon-Telemetry_Americas.html

How to receive....
https://www.rtl-sdr.com/receiving-satellite-tv-beacons-rtl-sdr-lnb/

KC9SGV