Hi,
Having started using the FrSky 2.4Ghz 8ch telemetry system for my FPV flying I really needed to get an rssi output from the receiver to feed into my EZOSD so I could see the info in the telemetry in my goggles.
Despite mentions that the latest V2 D8R's from FrSky have the rssi output on one of the side pins I found this not to be the case so I bought an interface kit here...
http://uav.org.pl/product.php?id_product=45 (http://uav.org.pl/product.php?id_product=45)
now available as surface mounted components
http://uav.org.pl/product.php?id_product=46 (http://uav.org.pl/product.php?id_product=46)
and added a short jumper lead inside the receiver and it is working perfectly :party:
Doing it this way on this receiver means It is simply a matter of plugging in the leads that come with the interface, adjusting the voltage levels with the onboard potentiometer (I have mine at the moment going from 0.7v to 3.2v) and the EZOSD has a lovely bit of rssi info to work with.
Hopefully I will get out tomorrow after work to give it a try in the air.
More info in this thread
http://rc-cam.pl/viewtopic.php?t=3353 (http://rc-cam.pl/viewtopic.php?t=3353)
and I think MarekM comes onto this forum sometimes (not sure though)
Paul
Hi, I am very interested in this, could you please give more details on where the jumper lead should be ?
No problem, I have another of my receivers to do today so will take some close up shots of where I soldered the link.
If you have the D8R v2 receiver then it has the advantage that there is a spare pin available on the side connector so it is easy to plug the external interface kit into the receiver so avoiding the need to hard wire it permanently.
so, photos later .......
Here are the photos showing the D8R v2 RSSI mod
(http://i1140.photobucket.com/albums/n575/pk-surfing/FrSky%20D8R%20v2/1-D8Rv2.jpg)
The receiver before I open it up
(http://i1140.photobucket.com/albums/n575/pk-surfing/FrSky%20D8R%20v2/2-peellabelfromsides.jpg)
The label needs peeling back on both sides only
(http://i1140.photobucket.com/albums/n575/pk-surfing/FrSky%20D8R%20v2/3-labelpeeledback.jpg)
view of the label peeled back so the receiver can be opened
(http://i1140.photobucket.com/albums/n575/pk-surfing/FrSky%20D8R%20v2/4-uncliptopcover.jpg)
top cover removed
(http://i1140.photobucket.com/albums/n575/pk-surfing/FrSky%20D8R%20v2/5-redled-weusetheothergreenled.jpg)
This shows the red led lit up, we use the GREEN led next to it to connect to for the rssi interface
(http://i1140.photobucket.com/albums/n575/pk-surfing/FrSky%20D8R%20v2/6-carefullyuncliptheboardfromthisendfirst.jpg)
I'm showing you the other side of the board, you don't actually need to remove it to just do the mod but I wanted to swap the wire antenna for longer ones.
(http://i1140.photobucket.com/albums/n575/pk-surfing/FrSky%20D8R%20v2/7-pinweuseonothersideofboard.jpg)
This is the spare pin we are lucky to have on this receiver, photo shows it alongside the label, we eventually use the pin labelled 'x' to pick up the signal for the inteface.
(http://i1140.photobucket.com/albums/n575/pk-surfing/FrSky%20D8R%20v2/8-%3Cbr%20/%3Elinkwiresolderedtothisendofgreenled.jpg)
Solder a fine flexible wire to this pad on the green led, this is VERY small so you need to use a suitable soldering iron for fine electronic work, and get the joint soldered in about 1 second... I use an Antex Cs 18W with a 1mm bit.
If you are not comfortable with this type of work then it's likely you will end up ruining the receiver !!!
(http://i1140.photobucket.com/albums/n575/pk-surfing/FrSky%20D8R%20v2/9-linksolderedtosparepin.jpg)
This is the link showing where it solders onto that spare pin.
(http://i1140.photobucket.com/albums/n575/pk-surfing/FrSky%20D8R%20v2/10-anotherviewoflink.jpg)
Another view of the completed link
(http://i1140.photobucket.com/albums/n575/pk-surfing/FrSky%20D8R%20v2/11-extendedantennawiresadded.jpg)
the completed job along with the longer FrSky antenna I added to make aerial positioning easier on my Jamara Roo je (Funsky)
(http://i1140.photobucket.com/albums/n575/pk-surfing/FrSky%20D8R%20v2/12-bothversionsofrssiinterface.jpg)
This shows both versions of the RSSI interface that I bought from UAV.ORG.PL
(http://i1140.photobucket.com/albums/n575/pk-surfing/FrSky%20D8R%20v2/13-allconnectedandtransmitterclose.jpg)
I have now connected the interface, powered the receiver, switched on the transmitter and have a multimeter connected to the interface output.....
This shows the voltage reading with the transmitter next to me on the desk.
The white wire from the interface already has a push connector on it and it goes onto the spare pin on the side of the D8R v2 that is marked 'x'.
The other lead from the interface goes to a servo connector on the receiver to pick up +ve and -ve to run the interface, if you dont have a spare connection you will need to use a 'Y' lead so you can connect the interface.
(http://i1140.photobucket.com/albums/n575/pk-surfing/FrSky%20D8R%20v2/14-transmitttermovedaway.jpg)
In range test mode I then moved the transmitter into another room and the voltage drops smoothly as required.
This output voltage is what I feed into my EZOSD so that it can show me the rssi % pecentage on the on screen display when flying.
(http://i1140.photobucket.com/albums/n575/pk-surfing/FrSky%20D8R%20v2/15-transmittermovedevenfurther.jpg)
Transmitter even further away and voltage is lower still.
The output voltage can be adjusted on the interface and to calibrate it correctly I will be doing a range test with a mate to help out, when the servo's start to failsafe I wil adjust the voltage so my EZOSD is showing a % percentage figure I know will be when I need to turn round (I have mine set to show 10%)
(http://i1140.photobucket.com/albums/n575/pk-surfing/FrSky%20D8R%20v2/16-transmitterswitchedoff.jpg)
And finally the voltage reading when the transmitter is turned off.
If anyone needs any more info just let me know.
:)
wow !!! great info. I will order some boards now...
Very detailed, spot on Paul great thread :)
More questions... I have the FRSKY receivers but the non telemetry ones ( no connectors on the side) can I still do this by hooking up a wire on the green LED ?
this is the one I have
http://www.giantcod.co.uk/24ghz-frsky-receiver-p-405722.html (http://www.giantcod.co.uk/24ghz-frsky-receiver-p-405722.html)
Yes it will still work fine, this link is to Marek's page on his website and I think the photo he shows is for the receiver you have.
http://uav.org.pl/en/elektronika/46-ue-01-miernik-rssi-by-mieciu-.html (http://uav.org.pl/en/elektronika/46-ue-01-miernik-rssi-by-mieciu-.html)
The main difference is that you will have a permanently attached signal wire from the receiver.
:)
great stuff !!! :)
Hello,
Paul - thanks for great how-to for RSSI Meter!
There are some new stuff in UAV.ORG.PL:
- LC filter for video power supply (based on Murata SMD chip):
(http://images8.fotosik.pl/1977/a95862b7ad2fc957med.jpg) (http://www.fotosik.pl)
weight - 3 gram including cables, dimension - 10x20mm
- various antennas (main - IBCrazy style)
(http://images8.fotosik.pl/1977/a95862b7ad2fc957med.jpg) (http://www.fotosik.pl)
(http://images8.fotosik.pl/1960/8da5b7a3bf64c5df.jpg) (http://www.fotosik.pl)
each antenna indywidually tuned and tested on spectrum and antenna analyzers
(http://images8.fotosik.pl/1960/e84efcce1aab9ec5med.jpg) (http://www.fotosik.pl)
(http://images8.fotosik.pl/1963/8b9c771ea46f178bm.jpg) (http://www.fotosik.pl/showFullSize.php?id=8b9c771ea46f178b)
video TX antennas with build-in low-pass filter (based in MiniCircuits SMD filters):
(http://images8.fotosik.pl/1963/acb75a29d913e8b6med.jpg) (http://www.fotosik.pl)
Marek
Marek,
Great to have you posting on the forum.
Everyone on the UK forum will be interested in new ready made antenna designs especially anything you have that are for 5.8ghz use as it seems more and more UK flyers are moving to 5.8 to avoid interference with fellow flyers if using 2.4ghz vtx.
I have looked on your site at the LC filter, it looks to be a well made piece of kit.
I know LC filters are used to stop unwanted ac interference travelling through the wiring, could you explain where would be the best place to fit your LC filter in a typical FPV setup ? (power feed to receiver ? power feed to camera ? to OSD feed ?)
Also would you expect more than one to be needed in a typical FPV installation ?
Paul
I like the Vee antenna with the low pass filter. do you do one for 1.3gHz ? will the filter stop the harmonics interfering with 2.4Ghz RC receivers ?
Quote from: pk-surfing on May 24, 2011, 08:46:07 AM
Everyone on the UK forum will be interested in new ready made antenna designs especially anything you have that are for 5.8ghz use as it seems more and more UK flyers are moving to 5.8 to avoid interference with fellow flyers if using 2.4ghz vtx.
(...)
Also would you expect more than one to be needed in a typical FPV installation ?
Paul
Hi Paul,
All kinds of my antennas can be make for 0.9 to 5.8 GHz bands.
For up to 4.4 GHz - I have good lab. For higher - only SWR measurements (which is enough to make not bad antenna),
so.... if anybody interested - PM me
Rearding LC filters: filtering interferences is a long story, as long as RC flying :)
Small SMD style filters can be used in various places: one is on main power "entry" = just after ESC, before RC receiver. Other - is video power supply, More - other electronic modules power supply (OSD, autopilots, etc). You can use one or more of its - but it depends of existing interferences in your instalation.
There are one more kind of filtering - signal lines from receiver/autopilot to each servo. For this - I just now preparing PCB whcich can be connected firectly to RC receiver.
Marek
Having trouble getting the rssi buffer to work on my non-telemetry receiver. Shows the same voltage regardless if the radio is on or off. Any help is appreciated.
uav.org.pl frsky rssi not working (http://www.youtube.com/watch?v=jHtWNrj3aYA#)
Hi Volto,
Is there any chance you could take a really close up clear photo of the receiver board to show the connection onto the led, one using macro mode on the camera would be ideal.
The connection point is so small that could be easy to get the new wire touching an adjacent track.
Its difficult to see on your video but of the two leds, one red and one green, it is the green one you have connected to isn't it ?
PK
Thanks for the reply. Here are some close-ups.
(http://img.photobucket.com/albums/v118/volto/frskyrssi0.jpg)
(http://img.photobucket.com/albums/v118/volto/frskyrssi1.jpg)
To show it's connected to green and not red:
(http://img.photobucket.com/albums/v118/volto/frskyrssi2.jpg)
I did notice that the green LED is REALLY dim. Maybe that has something to do with it? Also another strange thing that may be noteworthy is that the rssi voltage gradually climbs after turning on the receiver.
Thanks!
any ideas?
Hi,
I sent MarekM a PM to let him know you had posted a query about his RSSI circuit on the forum and hoped he would reply, I can only think he might be away (holiday ?) as I'm sure he would have replied.
MarekM would be able to tell you if there is a way of testing the circuit with it unsoldered from the receiver to make sure it is ok.
PK
Thanks! I also posted on the polish forum but I got no response there either. Maybe you are right and they are on holiday.
Does anyone know if this setup is still needed for D8R-II?
If not, can I just upgrade to D8R-SP via firmware?
Because with D8R-SP I heard you no longer need to buffer it if you are using OSD's that have digital in such as RVOSD5 and DOSD2.
Can anyone confirm this?
Thanks. :'(
Just upgrade your software as the hard ware in both units are the same
but get it off their site its under downloads rom 2 fdd100826 it think as i did it yesterday but you will need the usb or a serial cable to do it :)
Plus yes you will still need an inline buffer as Frsky where saying yes the D8RSP did do rssi so i ran out and bought one thinking plug and play ;D But i think what they where meaning was they had put a RSSI pin on the side so theres no need to do any soldering now
(http://s7.postimage.org/5ev4hz1gn/D8_RSP_RSSI.jpg) (http://postimage.org/image/5ev4hz1gn/)
Dave,
Have you managed to get this working successfuly with an OSD? If so, which one?
Cheers
Quote from: DPS-Dave on November 10, 2011, 03:24:03 AM
Just upgrade your software as the hard ware in both units are the same
but get it off their site its under downloads rom 2 fdd100826 it think as i did it yesterday but you will need the usb or a serial cable to do it :)
Plus yes you will still need an inline buffer as Frsky where saying yes the D8RSP did do rssi so i ran out and bought one thinking plug and play ;D But i think what they where meaning was they had put a RSSI pin on the side so theres no need to do any soldering now
(http://s7.postimage.org/5ev4hz1gn/D8_RSP_RSSI.jpg) (http://postimage.org/image/5ev4hz1gn/)
Hello,
Is it possible to upgrade the firmware on the D8R-II without the FrSky Upgrade Lite thing? I mean isn't it just a simple rs232 converter?
And could you please describe more in detail how to wire this, from the rssi out (Tx) port to a Eagletree OSD PRO? That buffer thing, is it neccesary for OSD PRO and where can you find a buffer?
Regards
Fredrik
Sorry no you need the lite to do the upgrade which the manual on how to wire up the lite can be a bit misleading but if you are uk based i'm more than happy to do for you :D
Getting the rssi you will need a buffer of some sort either the eagletree which if i where you i would go for or there is another one you can get off the guy on ebay in Hungry which works well with the frsky BUT again the guy doesn't speek english and trying to follow his discription takes a bit to understand lol
Quote from: DPS-Dave on January 09, 2012, 06:29:09 PM
Sorry no you need the lite to do the upgrade which the manual on how to wire up the lite can be a bit misleading but if you are uk based i'm more than happy to do for you :D
Getting the rssi you will need a buffer of some sort either the eagletree which if i where you i would go for or there is another one you can get off the guy on ebay in Hungry which works well with the frsky BUT again the guy doesn't speek english and trying to follow his discription takes a bit to understand lol
hehe, no sorry I live in Sweden. Should I get the firmware for d8r-ii or the sp? Oh I didn't know eagletree have a buffer? Which one is that? The logger?
Here the eagletree buffer
http://www.dpcav.com/xcart/product.php?productid=16500 (http://www.dpcav.com/xcart/product.php?productid=16500)
Going back to the frsky software if you download the rom2 folder from frsky when you connect your rx to you pc you get a uid number then you have a choice of which file you would like to send in this case you need to click on fdd_rx_-rev2_cppm_build110314.fr which in turn will release 5v at the rssi pin as in the pictures above
Looks like this RSSI buffer is no longer available at uav.org.pl. Anyone know where I can still get one? I may try building one myself, but I have zero experience with building circuits from schematics. I guess there is a first time for everything.
Hi,
id like to do something similar with the FrSky V8FR-II. is this possible?
Yeah, this item seems to have disappeared, anyone know where I can get one?
Keukpa
Anyone know if this exact mod will work on a d8r II Plus or is there another mod I'd need.
Got the dpcav buffer for my eagle tree osd.
Thanks