[Canberrauav] Sunday testing results Stephen Dade stephen_dade at hotmail.com Sun May 27 23:10:38 EST 2012 Hi everyone Today Jack, Tridge, Matt, Chris and myself did some long-range testing of the 5.8GHz and 900MHz radio links. Our results were: Mt Pleasant has significant interference at 900 MHz. So much so that we couldn't get any 900 MHz link to the UAV from the site. Whether or not this interference is from a legal/illegal emitter is debatable. I will check the databases at work tomorrow to see if there's a licence for a 915-928 MHz emitter in the area. The ground station was moved to Red Hill. This proved to be a good site. In addition to no radio interference there's tables, chairs and a cafe nearby :) The settings on the 900 MHz radio are unable to be remotely changed. This led to Tridge/Matt doing laps between CMAC and Mt Pleasant. We discovered that the CyberMugin is currently using the atmega1280 APM, rather than (what we assumed to be) the atmega2560 APM. They require different compilation options if you want the atmega to flash correctly. In the end, we did get decent telemetry and photos through the radio links to Red Hill. The software for the radio links is going to have to be altered to cope with dropped packets more gracefully though. The avionics battery (the lead acid battery) almost ran flat during the flight, causing voltage dropouts. This resulted in the pandaboard rebooting mid-flight. We are going to fit a voltage/current sensor to this battery for future flights. It should be noted that the battery should have lasted longer. We're not sure why the it was depleted so quickly. Thanks Stephen
[Canberrauav] Sunday testing results Jack Pittar jpittar at bigpond.net.au Mon May 28 17:20:58 EST 2012 On top of Mt Pleasant there are some antennas that look like mobile phone antennas. As such, they may be transmitting full power primarily in their allotted band, and only transmitting a relatively small amount in the LIPD band. Although this is enough to wipe us out, it might be calculated to be within limits at the range of any local inhabitation. The 7 amp hour Sealed Lead Acid battery was purchased new from Jaycar last week and fully charged before the event. A discharge test last night showed it had a bit more than half the advertised capacity when an estimation is made for being discharged at more than the 20 hour rate. We did a fair bit of powering systems on the ground before the flight. As with any of this experimental work, it always takes a lot longer than you expect. I drove into CMAC at about 830 am, and locked up at about 4:30 pm. The actual flight time was about 15 minutes. [Jack Pittar] -----Original Message----- From: canberrauav-bounces at canberrauav.com [mailto:canberrauav-bounces at canberrauav.com]On Behalf Of Stephen Dade Sent: Sunday, 27 May 2012 11:11 PM To: canberrauav at canberrauav.com Subject: [Canberrauav] Sunday testing results Hi everyone Today Jack, Tridge, Matt, Chris and myself did some long-range testing of the 5.8GHz and 900MHz radio links. Our results were: Mt Pleasant has significant interference at 900 MHz. So much so that we couldn't get any 900 MHz link to the UAV from the site. Whether or not this interference is from a legal/illegal emitter is debatable. I will check the databases at work tomorrow to see if there's a licence for a 915-928 MHz emitter in the area. The ground station was moved to Red Hill. This proved to be a good site. In addition to no radio interference there's tables, chairs and a cafe nearby :) The settings on the 900 MHz radio are unable to be remotely changed. This led to Tridge/Matt doing laps between CMAC and Mt Pleasant. We discovered that the CyberMugin is currently using the atmega1280 APM, rather than (what we assumed to be) the atmega2560 APM. They require different compilation options if you want the atmega to flash correctly. In the end, we did get decent telemetry and photos through the radio links to Red Hill. The software for the radio links is going to have to be altered to cope with dropped packets more gracefully though. The avionics battery (the lead acid battery) almost ran flat during the flight, causing voltage dropouts. This resulted in the pandaboard rebooting mid-flight. We are going to fit a voltage/current sensor to this battery for future flights. It should be noted that the battery should have lasted longer. We're not sure why the it was depleted so quickly. Thanks Stephen
[Canberrauav] Sunday testing results Stephen Dade stephen_dade at hotmail.com Tue May 29 00:03:12 EST 2012 Further to Jack's comments, I can confirm that there's a mobile phone tower there (operated by Vodafone/Telstra) using the 900-915.5MHz bands (among others). It is most likely that there's some "leakage" into other bands. The full list is at: http://web.acma.gov.au/pls/radcom/site_search.site_lookup?pSITE_ID=130647 I'll check for other mobile phone towers near Kingaroy airport. I couldn't find any obvious (licensed) radiocommunications transmitters around Mt Pleasant (or Kingaroy for that matter) in the 915-928MHz and 5.8-5.9GHz bands. -Stephen From: canberrauav-bounces at canberrauav.com [mailto:canberrauav-bounces at canberrauav.com] On Behalf Of Jack Pittar Sent: Monday, 28 May 2012 5:21 PM To: canberrauav at canberrauav.com Subject: Re: [Canberrauav] Sunday testing results On top of Mt Pleasant there are some antennas that look like mobile phone antennas. As such, they may be transmitting full power primarily in their allotted band, and only transmitting a relatively small amount in the LIPD band. Although this is enough to wipe us out, it might be calculated to be within limits at the range of any local inhabitation. The 7 amp hour Sealed Lead Acid battery was purchased new from Jaycar last week and fully charged before the event. A discharge test last night showed it had a bit more than half the advertised capacity when an estimation is made for being discharged at more than the 20 hour rate. We did a fair bit of powering systems on the ground before the flight. As with any of this experimental work, it always takes a lot longer than you expect. I drove into CMAC at about 830 am, and locked up at about 4:30 pm. The actual flight time was about 15 minutes. [Jack Pittar] -----Original Message----- From: canberrauav-bounces at canberrauav.com [mailto:canberrauav-bounces at canberrauav.com]On Behalf Of Stephen Dade Sent: Sunday, 27 May 2012 11:11 PM To: canberrauav at canberrauav.com Subject: [Canberrauav] Sunday testing results Hi everyone Today Jack, Tridge, Matt, Chris and myself did some long-range testing of the 5.8GHz and 900MHz radio links. Our results were: Mt Pleasant has significant interference at 900 MHz. So much so that we couldn't get any 900 MHz link to the UAV from the site. Whether or not this interference is from a legal/illegal emitter is debatable. I will check the databases at work tomorrow to see if there's a licence for a 915-928 MHz emitter in the area. The ground station was moved to Red Hill. This proved to be a good site. In addition to no radio interference there's tables, chairs and a cafe nearby :) The settings on the 900 MHz radio are unable to be remotely changed. This led to Tridge/Matt doing laps between CMAC and Mt Pleasant. We discovered that the CyberMugin is currently using the atmega1280 APM, rather than (what we assumed to be) the atmega2560 APM. They require different compilation options if you want the atmega to flash correctly. In the end, we did get decent telemetry and photos through the radio links to Red Hill. The software for the radio links is going to have to be altered to cope with dropped packets more gracefully though. The avionics battery (the lead acid battery) almost ran flat during the flight, causing voltage dropouts. This resulted in the pandaboard rebooting mid-flight. We are going to fit a voltage/current sensor to this battery for future flights. It should be noted that the battery should have lasted longer. We're not sure why the it was depleted so quickly. Thanks Stephen
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