MartynColes Posted November 26, 2014 Share Posted November 26, 2014 Hi Chris, Yes I did find those manuals thanks, but they are quite a lot behind the present version of firmware (now 2.0.13) and some of the pages don't seem to exist. e.g. "Templates 13/13" sounded nice and useful, but nothing like that seems to be present anymore. It seems the manuals you describe are for series 1.x.xx of the firmware, and since series 2.x.xx has been around for almost a year now, it seems a pity that the manual hasn't caught up. None the less, I am very pleased I chose the Taranis as it appears to be so flexible in its programming. Although without help on a forum such as this, some of the problems I have encountered would have been very frustrating. Kind regards, Martyn C Quote Link to comment Share on other sites More sharing options...
Spice Cat Posted December 23, 2014 Share Posted December 23, 2014 Sorry if this has been dealt with before but I am looking at a telemetry Rx and believe the X8R is the one for me. All I need it to do is to watch the altitude as it will be used on the FVP gear. Is this correct unit???? Regards. Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted December 23, 2014 Share Posted December 23, 2014 Yeap - the X8R does deliver telemetry. BEB Quote Link to comment Share on other sites More sharing options...
Spice Cat Posted December 23, 2014 Share Posted December 23, 2014 Thanks BEB. I will be putting said rx in my new Go Discover. (Thanks Santa) Quote Link to comment Share on other sites More sharing options...
Kevin Fairgrieve Posted December 23, 2014 Share Posted December 23, 2014 Whilst the X8R is telemetry enabled, to monitor altitude you will need an additional sensor, in the form of the variometer. FrSky Variometer. Kev Quote Link to comment Share on other sites More sharing options...
Daithi O Buitigh Posted December 23, 2014 Share Posted December 23, 2014 A variometer really only measures the rate of climb (or sink) and isn't an altimeter. You need a GPS module (btw the Taranis already has voltage and signal strength telemetry enabled on the X8R receiver) Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted December 24, 2014 Share Posted December 24, 2014 While you are quite correct Daithi that a variometer does not normally measure altitude, only change in altitude, the FrSky so-called variometer does! It includes a atmospheric pressure sensor that can be zeroed at ground level and gives you altitude AGL. The "high precision" variant also claims a very high accuracy of 10cm! BEB Quote Link to comment Share on other sites More sharing options...
Daithi O Buitigh Posted December 24, 2014 Share Posted December 24, 2014 I use the GPS module and, from my gliding days when the variometer was only used to go "Oh gee, golly, gosh, I've hooked a thermal", and the altimeter was to tell you how high you were . I guessed that was how the Taranis one worked (it doesn't mention on the T9 website that it does anything different) Quote Link to comment Share on other sites More sharing options...
GONZO Posted December 24, 2014 Share Posted December 24, 2014 Most people doing FPV get the hight, distance, etc over the video link by using an OSD(On Screen Display). The RC link is used just for control. Thus, if as it seems you are using 2.4gHz for control, IMO the L9R non telemetry long range reciever would be more appropriate used in conjunction with an OSD. Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted December 24, 2014 Share Posted December 24, 2014 I agree Daithi, technical details on the T9 website are a bit sparse, HK's version here has more detail, including range and accuracy information. GPS can be used as an altimeter - but generally speaking its not very accurate - GPS accuracy in 'z' is generally less than in 'x' and 'y'. Also it depends very much on how the GPS module has been programmed. "Raw" GPS data gives the height above the geoid which, depending on where you are on the earth's surface, can be a long way different from AGL. Having said that most of the GPS systems we use effectively take "home" (ie initialisation point) as the datum, subtracting that value from all subsequent values to give you an approximation to AGL - however while that is useful it doesn't solve the basic accuracy issues. As far as I know the OSD systems available use GPS altitude with the associated errors. This is why top-grade drones are nearly always fitted with some sort of altitude measurement system other than GPS. BEB Quote Link to comment Share on other sites More sharing options...
GONZO Posted December 24, 2014 Share Posted December 24, 2014 OSD units are available with barometric sensors. Quote Link to comment Share on other sites More sharing options...
Spice Cat Posted December 24, 2014 Share Posted December 24, 2014 Don't think I'll bother with the high preision version as +/- 10m is good for me!! Quote Link to comment Share on other sites More sharing options...
Spice Cat Posted February 1, 2015 Share Posted February 1, 2015 Sorry if this has been asked before but I recently 'invested' in a new rx with telemetry and found on a foamy at less than two hundred yards I was getting a warning as RRSI critical. Not wanting to take my eyes off the model I could not check the reading, but what is the recommended minimum RSSI or is that an ananswerable question?? Regards. Quote Link to comment Share on other sites More sharing options...
Jim Mchugh Posted February 1, 2015 Share Posted February 1, 2015 Spice Cat, What receiver were you using when you got the Low RSSI...? I've got some issues with some of the small 4 channel receivers... Cheers! Quote Link to comment Share on other sites More sharing options...
Spice Cat Posted February 1, 2015 Share Posted February 1, 2015 Hello Jim, I was using an X8R on a Go Discover flying wing. Cheers. Quote Link to comment Share on other sites More sharing options...
Chris Bott - Moderator Posted February 1, 2015 Share Posted February 1, 2015 What are your alarm levels set at SC? My Low RSSI is set at 45 and Critical RSSI at 42. I think these are the default settings. It's a "per model" setting. Quote Link to comment Share on other sites More sharing options...
Jim Mchugh Posted February 1, 2015 Share Posted February 1, 2015 Spice Cat, My problem is around the D4R-II 4 channel RX. In "Range Test" mode I only get 15 paces range in a faomie RadJet. No metal / carbon etc. I tried a total of 3 different D4R-II receivers on 2 different Taranis transmitters and they all did the same thing. Tested against a D8R-XP receiver and all is fine, I get a good 30 paces in range test mode. So now I've gone for the X4R receiver which also has 4 channels and telemetry. FrSkys own specs show differing current requirements for the receivers: D4R-II: 60mA X4R: 100mA So is the FrSky RSSI reading calculated by an average of both ends and the D4R-II is not transmitting back to the ground with the same amount of RF power as the X4R...? The mystery continues... Still awesome kit for the money! Quote Link to comment Share on other sites More sharing options...
Chris Bott - Moderator Posted February 1, 2015 Share Posted February 1, 2015 From the manual:- Probably the most important telemetry value is RSSI, which is an indication of how much signal the receiver in the model is seeing from the radio, and will warn you in advance if you are at risk of losing control be it due to external interference, excessive distance, badly oriented or damaged antennas etc. The telemetry settings page gives you 2 alarm levels you can set that will be announced in clear voice ("RF signal low" and "RF signal critical". They are set by default to levels that have been considered suitable and safe for normal line of sight flight (45 and 42), but if you want to adjust them yourself the following explanations will be useful: RSSI on FrSky equipment is represented using a logarithmic scale (dB), not in %. This means that when RSSI is high, a small difference in distance between the transmitter and receiver will lead to a big change of the RSSI value. It is perfectly normal to see a value of about 100 when next to the model, and already down in the 70's by the time you've walked to the other end of the field. When you have a reading of 50, it will however take a lot of extra distance to reach the alarm level of 45. The basic approximation rule is that a doubling of distance between pilot and model will result in a drop of 6dB of the RSSI value, which should make the previous explanation clear: If you are 5m away from the model it only takes another 5m to reduce RSSI by 6dB, but if you are 600m away from the model it will then take another 600m to reduce the value by the "same" 6dB. Loss of control will happen when RSSI reaches a value of about 38, so setting an alarm at 10 is useless. From the above explanation you can see that between the default critical alarm (42) and usual practical loss of control we have a margin of about 4dB, or range factor of around 1.5. The alarms are thus rather conservative, and in normal conditions even if you heard the critical alarm you would still be far from losing control (you should be at around >1000m distance, with another 500m to spare). Intermittent loss due to local fades and antenna orientation mismatches could however get more and more frequent. Quote Link to comment Share on other sites More sharing options...
Frank Skilbeck Posted February 1, 2015 Share Posted February 1, 2015 Is RSSI (Received signal strength indicator) a measure of the signal strength or signal quality, i.e. what would a set of corrupted data (2 systems transmitting on the same channel) do to RSSI? does it still read the signal strength or does it take into account the quality of the data. If it's only measuring the received signal strength then will it alarm if there is interference or is this recorded as signal strength. Quote Link to comment Share on other sites More sharing options...
Chris Bott - Moderator Posted February 1, 2015 Share Posted February 1, 2015 We can't think of 2.4Ghz spread spectrum systems like we did 27 or 35Mhz narrow band single frequency systems Frank. The Tx and Rx hop around between many different frequencies, keeping in sync with each other. So they usually hit an empty frequency and sometimes hit a used frequency. This happens very quickly and all the time, and makes it possible to measure received signal level of just the "wanted" transmission. You are right though, it's not the whole story. The FrSky system, for example, doesn't report frame losses and holds like the Spektrum system does. What RSSI is useful for, though, is for knowing if your aerial placement is good. During range checks and during flying, you'll know if you have a receive level problem well before you lose control. Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted February 1, 2015 Author Share Posted February 1, 2015 Posted by Spice Cat on 01/02/2015 14:25:37: Hello Jim, I was using an X8R on a Go Discover flying wing. Cheers. Did you stick with the PCB aerials or swap them for wire ended ones? I've flown a number of X8 and X6 receivers in various model types with no reduction in range or increase in low-signal warnings compared to D8/D6 receivers. Have you got another receiver you could substitute for a comparison? Quote Link to comment Share on other sites More sharing options...
Spice Cat Posted February 2, 2015 Share Posted February 2, 2015 Sorry for the delay. I have stuck with the stock items but may have to adjust their position in the model. I do lay them at 90 to each other. Will have a fiddle about. Regards. Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted February 2, 2015 Share Posted February 2, 2015 I only use 8XR's and I have to said I've never had a range issue. Is there any carbon in the flying wing SC? BEB Quote Link to comment Share on other sites More sharing options...
Spice Cat Posted February 2, 2015 Share Posted February 2, 2015 Don't think so, it's the Go Discover foamy. Quote Link to comment Share on other sites More sharing options...
John Privett Posted February 15, 2015 Share Posted February 15, 2015 Posted by John Privett on 14/08/2014 22:55:57: And indeed, I too had expected a servo-type plug on the other end of the cables. But as I don't really have space in the Speedo to add any sensors - nor any point in a current or voltage sensor - I won't be needing to plug anything into the Smart port for a while. Unless I find somewhere to squeeze the GPS-sensor in. I suppose it would fit easily where the old rx was. But I don't suppose it would work too well sitting immediately under the (carbon) canopy! Well, despite what I said earlier about lack of space, and following the recent discussion on variometers, my Speedo now has a variometer installed. It's behind the rx - the space left by the old rx is now occupied by a second battery - doubling-up battery capacity. It was a five-minute job to crimp a servo plug on the end of the lead supplied with the XR4 for the variometer. Quote Link to comment Share on other sites More sharing options...
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