The AO-51 command team has reloaded the software and the repeater is operational.
We will turn the SQRX receiver on to L-band on Saturday for those wanting to uplink to the BB.
73, Gould, WA4SXM for the A0-51 Command team Kevin, WA6FWF Drew, KO4MA
It seems that most of the time when there is a pass in my area from FO-29, there are no users on the bird. FO-29 is an excellent & loud satellite, and it requires very little output power.
I just spent 10 minutes or so calling cq, and listening up and down the passband, and there is no one around. It gets boring listening to myself on the downlink! This is generally the case, no matter the time of day or night.
Please, those of you who have the equipment - FO-29 is alive and well, let's use it!
73 de W4AS Sebastian
----- Original Message ----- From: "Sebastian" w4as@bellsouth.net To: "AMSAT BB" amsat-bb@amsat.org Sent: Saturday, August 30, 2008 6:41 AM Subject: [amsat-bb] FO-29 users where are you?
It seems that most of the time when there is a pass in my area from FO-29, there are no users on the bird. FO-29 is an excellent & loud satellite, and it requires very little output power.
I just spent 10 minutes or so calling cq, and listening up and down the passband, and there is no one around. It gets boring listening to myself on the downlink! This is generally the case, no matter the time of day or night.
Please, those of you who have the equipment - FO-29 is alive and well, let's use it!
73 de W4AS Sebastian
Hi Sebastian, W4AS
Over Europe there are many users of FO-29 but all of them are equipped with low noise preamplifiers antenna mounted and good antennas.
By the way when FO-29 comes up at AOS it is very common to listen for many stations trying to get back for their own signals back and fort all over the pass-band without success because their receiving sensitivity is low.
Since the FO-29 sensitivity is very high only a very low EIRP is necessary to be translated with sufficient power for a decent QSO in SSB or CW provided that the ground station sensitivity is adeguate as well.
Quoting many succesfull ground stations using FO-29 over EU it is possible to state that for good operation all over the orbit from AOS to LOS a minimum ratio G/T = - 2 dB is necessary.
As an example:
Antenna gain G = 13 dBi = 20 in power factor Overall receiving Noise Figure = 0.45 dB equal to T= 31.6 kelvin
G/T = 20 / 31.6 = 0.63 and 10 log 0.63 = -2 dB 10
Another example:
In order to get about the same ratio G/T = - 2 dB and following the above formula we see that it is possible to use an antenna with G= 16 dBi = 40 in power ratio and a greater receiving system overall Noise Figure = 0.9 dB corresponding to T = 67 kelvin
And so on..........
Many years ago the recommended ratio G/T for every satellite was supplied by AMSAT
The above G/T = -2 dB for FO-29 has been experimentally derived knowing the working conditions of many succesful stations in QSO with me over Europe.
73" de
i8CVS Domenico
On 30 Aug 2008 at 15:34, i8cvs wrote:
By the way when FO-29 comes up at AOS it is very common to listen for many stations trying to get back for their own signals back and fort all over the pass-band without success because their receiving sensitivity is low.
Since the FO-29 sensitivity is very high only a very low EIRP is necessary to be translated with sufficient power for a decent QSO in SSB or CW provided that the ground station sensitivity is adeguate as well.
Same thing over here especially for some CW station who crank up their power until they hear their own downlink and they start to call CQ using the same power level.
THE CASCADING EFFECT
Those using just enough power have to increased their power too until the pass band became unusable. Even with the lowest power setting on some rig the EIRP is still too high. A way compensate they should stay off pointing in elevation this will help reducing their signal at the satellite.
It is not an easy concept but the using "just enough power" as stated in many radio act and regulations take his full sense on satellite operation. It his hard to condemn when the operator is at his first qso's but when "veteran" are involved it is a bit hard to understand their motive? (Just remember the chirpy CW signal on HF in the past some station get tag as the always chirpy one!)
Just to pointed that on AO-7 on August 28 i was able to have a QSO with F2IL Jean-Marie the satellite is in the best shape since a long time no more heavy distorted audio. I was trying the double sat FO-29/AO-7 idea but with not too much success. It is hard here as per my simulation to have both satellite in range but european pass offer many pass where both sat are in range over the same area.
Who will be the first! we have the labour day week end here to try this concept.
"-"
Luc Leblanc VE2DWE Skype VE2DWE www.qsl.net/ve2dwe WAC BASIC CW PHONE SATELLITE
participants (4)
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Gould Smith -
i8cvs -
Luc Leblanc -
Sebastian