Re: [amsat-bb] EO-80 FM Transponder Tested
Thats very good news, Hopefully the two get activated before field day? Im most looking forward to EO-80, It should be like AO-27 with 500Mw or 1W. Good to know both are working well and wish a long life to them.
73 KE8AKW
Nick,
It should be even stronger than AO-27's 500 mW, AO-27 had a 70cm downlink, the EO-80 downlink is on 2 meters, so EO-80's signal should be up to 9 dB stronger than AO-27 (12 dB stronger if they run it at 1 watt).
73,
Paul, N8HM
On Tue, Jun 16, 2015 at 7:49 PM, Nicholas Mahr nicholasmahr1@gmail.com wrote:
Thats very good news, Hopefully the two get activated before field day? Im most looking forward to EO-80, It should be like AO-27 with 500Mw or 1W. Good to know both are working well and wish a long life to them.
73 KE8AKW _______________________________________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
Can you explain the 6dB advantage 2m has over 70cm? I've seen it here on the amsat-bb, and in the mesh realm when comparing 2.4GHz and 5.8GHz WiFi gear, but it still hasn't "clicked."
73 de KE5GDB
On Tue, Jun 16, 2015 at 6:56 PM, Paul Stoetzer n8hm@arrl.net wrote:
Nick,
It should be even stronger than AO-27's 500 mW, AO-27 had a 70cm downlink, the EO-80 downlink is on 2 meters, so EO-80's signal should be up to 9 dB stronger than AO-27 (12 dB stronger if they run it at 1 watt).
73,
Paul, N8HM
On Tue, Jun 16, 2015 at 7:49 PM, Nicholas Mahr nicholasmahr1@gmail.com wrote:
Thats very good news, Hopefully the two get activated before field day?
Im
most looking forward to EO-80, It should be like AO-27 with 500Mw or 1W. Good to know both are working well and wish a long life to them.
73 KE8AKW _______________________________________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership.
Opinions expressed
are solely those of the author, and do not reflect the official views of
AMSAT-NA.
Not an AMSAT-NA member? Join now to support the amateur satellite
program!
Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
*9dB (typo)
On Wed, Jun 17, 2015 at 9:42 AM, Andrew Koenig ke5gdb@gmail.com wrote:
Can you explain the 6dB advantage 2m has over 70cm? I've seen it here on the amsat-bb, and in the mesh realm when comparing 2.4GHz and 5.8GHz WiFi gear, but it still hasn't "clicked."
73 de KE5GDB
On Tue, Jun 16, 2015 at 6:56 PM, Paul Stoetzer n8hm@arrl.net wrote:
Nick,
It should be even stronger than AO-27's 500 mW, AO-27 had a 70cm downlink, the EO-80 downlink is on 2 meters, so EO-80's signal should be up to 9 dB stronger than AO-27 (12 dB stronger if they run it at 1 watt).
73,
Paul, N8HM
On Tue, Jun 16, 2015 at 7:49 PM, Nicholas Mahr nicholasmahr1@gmail.com wrote:
Thats very good news, Hopefully the two get activated before field day?
Im
most looking forward to EO-80, It should be like AO-27 with 500Mw or 1W. Good to know both are working well and wish a long life to them.
73 KE8AKW _______________________________________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership.
Opinions expressed
are solely those of the author, and do not reflect the official views
of AMSAT-NA.
Not an AMSAT-NA member? Join now to support the amateur satellite
program!
Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
-- Andrew Koenig
Paul beat me to the punch as I was typing up my response, but I'm sending it anyway:
Path Loss. -> function of lambda (wavelength) squared. So all other things being equal (antenna gains, power levels, range, etc.), you can look at the power ratio of the two.
Rough calculation (going from 2m to 70cm): 10log[(0.70/2)^2] = -9.1 dB OR Rough calculation (going from 70cm to 2m): 10log[(2/0.7)^2] = +9.1 dB
The thing to watch out for is antenna gains on the ground. The arrow for example has more gain on 70cm (7el) than it does on 2m (3el). So while 2m has a 9-ish dB improvement over 70cm in terms of path loss, the receiver may not see the full 9dB because of the difference in gains on the antenna between the two bands.
Again VERY rough approximation (for demonstration purposes only): 3el yagi -> call it 7.5 ish dB of gain 7el yagi -> call it 11.5 ish dB of gain so, about 4 dB of LOST gain (going from 70cm to 2m using the arrow example).
So net gain going from 70cm to 2m (all other things equal except the gains on the arrow antenna) 9dB - 4dB = 5dB
so your typo was actually fairly close :-) for those planning to use their existing setup for the new birds.
-Zach, KJ4QLP
On 6/17/2015 10:43 AM, Andrew Koenig wrote:
*9dB (typo)
On Wed, Jun 17, 2015 at 9:42 AM, Andrew Koenig ke5gdb@gmail.com wrote:
Can you explain the 6dB advantage 2m has over 70cm? I've seen it here on the amsat-bb, and in the mesh realm when comparing 2.4GHz and 5.8GHz WiFi gear, but it still hasn't "clicked."
73 de KE5GDB
On Tue, Jun 16, 2015 at 6:56 PM, Paul Stoetzer n8hm@arrl.net wrote:
Nick,
It should be even stronger than AO-27's 500 mW, AO-27 had a 70cm downlink, the EO-80 downlink is on 2 meters, so EO-80's signal should be up to 9 dB stronger than AO-27 (12 dB stronger if they run it at 1 watt).
73,
Paul, N8HM
On Tue, Jun 16, 2015 at 7:49 PM, Nicholas Mahr nicholasmahr1@gmail.com wrote:
Thats very good news, Hopefully the two get activated before field day?
Im
most looking forward to EO-80, It should be like AO-27 with 500Mw or 1W. Good to know both are working well and wish a long life to them.
73 KE8AKW _______________________________________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership.
Opinions expressed
are solely those of the author, and do not reflect the official views
of AMSAT-NA.
Not an AMSAT-NA member? Join now to support the amateur satellite
program!
Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
-- Andrew Koenig
Free space path loss is dependent on frequency. All things being equal (distance, antenna gain on both ends, etc), a 2 meter signal has about a 9 dB advantage over a 70cm signal.
Here's an explanation:
http://www.radio-electronics.com/info/propagation/path-loss/free-space-formu...
73,
Paul, N8HM
On Wed, Jun 17, 2015 at 10:42 AM, Andrew Koenig ke5gdb@gmail.com wrote:
Can you explain the 6dB advantage 2m has over 70cm? I've seen it here on the amsat-bb, and in the mesh realm when comparing 2.4GHz and 5.8GHz WiFi gear, but it still hasn't "clicked."
73 de KE5GDB
On Tue, Jun 16, 2015 at 6:56 PM, Paul Stoetzer n8hm@arrl.net wrote:
Nick,
It should be even stronger than AO-27's 500 mW, AO-27 had a 70cm downlink, the EO-80 downlink is on 2 meters, so EO-80's signal should be up to 9 dB stronger than AO-27 (12 dB stronger if they run it at 1 watt).
73,
Paul, N8HM
On Tue, Jun 16, 2015 at 7:49 PM, Nicholas Mahr nicholasmahr1@gmail.com wrote:
Thats very good news, Hopefully the two get activated before field day? Im most looking forward to EO-80, It should be like AO-27 with 500Mw or 1W. Good to know both are working well and wish a long life to them.
73 KE8AKW _______________________________________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
-- Andrew Koenig
Thanks! That website explained it very well, and seeing the formulas really helped.
73 de KE5GDB
On Wed, Jun 17, 2015 at 9:51 AM, Paul Stoetzer n8hm@arrl.net wrote:
Free space path loss is dependent on frequency. All things being equal (distance, antenna gain on both ends, etc), a 2 meter signal has about a 9 dB advantage over a 70cm signal.
Here's an explanation:
http://www.radio-electronics.com/info/propagation/path-loss/free-space-formu...
73,
Paul, N8HM
On Wed, Jun 17, 2015 at 10:42 AM, Andrew Koenig ke5gdb@gmail.com wrote:
Can you explain the 6dB advantage 2m has over 70cm? I've seen it here on
the
amsat-bb, and in the mesh realm when comparing 2.4GHz and 5.8GHz WiFi
gear,
but it still hasn't "clicked."
73 de KE5GDB
On Tue, Jun 16, 2015 at 6:56 PM, Paul Stoetzer n8hm@arrl.net wrote:
Nick,
It should be even stronger than AO-27's 500 mW, AO-27 had a 70cm downlink, the EO-80 downlink is on 2 meters, so EO-80's signal should be up to 9 dB stronger than AO-27 (12 dB stronger if they run it at 1 watt).
73,
Paul, N8HM
On Tue, Jun 16, 2015 at 7:49 PM, Nicholas Mahr <nicholasmahr1@gmail.com
wrote:
Thats very good news, Hopefully the two get activated before field
day?
Im most looking forward to EO-80, It should be like AO-27 with 500Mw or
1W.
Good to know both are working well and wish a long life to them.
73 KE8AKW _______________________________________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views
of
AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership.
Opinions
expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite
program!
Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
-- Andrew Koenig
participants (4)
-
Andrew Koenig -
Nicholas Mahr -
Paul Stoetzer -
Zach Leffke