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Old Feb 03, 2012, 07:52 AM
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Maybe I should buy this: http://www.flytron.com/video-equipme...regulator.html

Another thing - these two circuits look very similair:

http://www.flytron.com/osd-headtrack...nt-sensor.html

http://www.flytron.com/sensors/64-ul...nt-sensor.html

the 50A and the 100A current sensor...On the 50A version theres also written 100A...So is it a trick is the 50A version also capable of 100A input?

Is there any disadvantage of using a 100A current sensor if your total amps at the current setup is below 50A, but maybe a future setup could be above 50A so I'm thinking it would be wiser to buy the 50A setup?

Another thing, introducing connectors into the system (so that I could use this system on multiple planes), reduces the "safety" of the system, but is it really such a big deal?
Can I have connectors between the current sensor and the osd;...between the camera and the osd;....between the vtx and the osd and finally between the gps and osd
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Old Feb 03, 2012, 08:35 AM
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Originally Posted by msev View Post
the 50A and the 100A current sensor...On the 50A version theres also written 100A...So is it a trick is the 50A version also capable of 100A input?
No, it's not a "trick". This sensor is basically only a so called "shunt" resistor. So the other current sensors have different resistors soldered onto the board.
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Originally Posted by msev View Post
Is there any disadvantage of using a 100A current sensor if your total amps at the current setup is below 50A, but maybe a future setup could be above 50A so I'm thinking it would be wiser to buy the 50A setup?
It's a matter of rersolution and acuracy. Obviousely with the 100A sensor, but constant currents below 50A, you would only use half of the resolution of the AD converter in the atmel CPU and half the precision means double the error. If you still can live with that there is nothing wrong with this aproach.
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Another thing, introducing connectors into the system (so that I could use this system on multiple planes), reduces the "safety" of the system, but is it really such a big deal?
It's a trade off of course, but I'd say it's ok.
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Originally Posted by msev View Post
Can I have connectors between the current sensor and the osd;...between the camera and the osd;....between the vtx and the osd and finally between the gps and osd
Sure, the connectors will introduce the possibility that they disconnect, but if the wires are soldered in they could break loose too. It's adviseable to carefully inspect your system before you fly, or at least before your flying day. That way I'm sure you can avoid certain classes of failures.

Markus
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Old Feb 03, 2012, 11:23 AM
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Originally Posted by alex57russ View Post
Hi all !
I have connected and have checked up OSD, works!!!
But I have 2 questions:
1) At me the current sensor and the battery on pin A5 and A6 isn't connected, but volts and the current expense shows on the screen, why?
2) Why under text OSD blackout moves aside? (As on a photo)

Attachment 4601710
1)
The OSD can't detect if the voltage-divider and current-sensor is attached or not. If nothing is connected, it will more or less read random values (they depend on other inputs, charge nearby etc).

2) I have seen this problem before, but can't remember who it was? Have you connected dimming before the capacitor?


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Originally Posted by msev View Post
there isn`t a 7V ubec...thanks for the answers anyway, gotta wait on how Dennis has the power made before proceeding...i have every other part except power for it
You can use any BEC or UBEC, it shouldn't be very critical. I power OSD, GPS, camera and Video-tx with a single turnigy 3A UBEC. I have added a couple of LC filters on the camera and video-tx supply, but that's about it.

I don't think 3S lipo is a problem for the onboard regulator, if you only use it for the OSD. But if you also use it to power GPS, it might get too hot.
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Old Feb 03, 2012, 12:06 PM
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Dennis are you talking about this one: http://www.hobbyking.com/hobbycity/s...idProduct=4319

How accurate is it's output voltage?

How bad is it for the gps if the voltage isn't spot on...I've read reviews on some other ubecs that are currently in stock at HK that they fluctuate for about 0.5V? Will that kill or damage the gps (if it's 5.5V)?
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Old Feb 03, 2012, 06:27 PM
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Originally Posted by msev View Post
Dennis are you talking about this one: http://www.hobbyking.com/hobbycity/s...idProduct=4319

How accurate is it's output voltage?

How bad is it for the gps if the voltage isn't spot on...I've read reviews on some other ubecs that are currently in stock at HK that they fluctuate for about 0.5V? Will that kill or damage the gps (if it's 5.5V)?
Yup, that's the one I use. As I remember it outputs > 5 volts, but can't remember the exact voltage. I think it was around 5.5 volts as well. On one plane I have added a diode on front of the camera to get < 5 volts, but isn't really necessary. The 5.5 volts is fine for the Arduino - but I can't say if it's okay for the GPS. You will have to check datasheet/schematic for you specific GPS-device.
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Old Feb 04, 2012, 05:10 AM
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I have the same gps like you Dennis.
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Old Feb 04, 2012, 05:13 AM
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Originally Posted by msev View Post
I have the same gps like you Dennis.
I have this one from flytron:
http://flytron.com/osd-headtrackers/...ps-module.html

It says:
3.3 to 5.5v supply voltage (Default 5v, need a small hack for 3.3v usage)


So you should be fine with 5-5.5 volt BEC/UBEC for OSD/GPS.
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Old Feb 04, 2012, 05:56 AM
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How embarrassing, how could I have missed that...Sorry guys..
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Old Feb 07, 2012, 03:01 AM
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Hi...

I have the EM-411 GPS from dealextreme...

http://www.dealextreme.com/p/em-411-...-chipset-80037

It works at 4800bps by default... Can I adjust a higher bps-rate. Are there commands to config the Modul ?

Thanks...
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Old Feb 07, 2012, 10:51 AM
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I thought of another use for the diy osd (well at least a very basic version of it)...If possible I don't know.

Well a lot of off the shelf LCDs which people use on groundstations has the blue or blackscreen of death issue, when the video signal begins to weaken.

Would you think that with having an arduino on the ground overlaying groundstation voltage on to the screen could avoid that black-bluescreen?
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Old Feb 07, 2012, 02:43 PM
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Originally Posted by msev View Post
I thought of another use for the diy osd (well at least a very basic version of it)...If possible I don't know.

Well a lot of off the shelf LCDs which people use on groundstations has the blue or blackscreen of death issue, when the video signal begins to weaken.

Would you think that with having an arduino on the ground overlaying groundstation voltage on to the screen could avoid that black-bluescreen?
Sounds like it would be fairly simple. You'd basically just strip out the code that gathers and processes the GPS information and leave the code that reads the A2D register for the voltage divider and display that information on the screen. Then you'd splice into the video signal coming from the receiver and going to the ground station display. You'd have to also move the display location of the voltage overlay so it doesn't interfere with the text already being overlay by the DIY OSD on the plane.
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Old Feb 07, 2012, 02:49 PM
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Yep that's the plan, but the big unknown is if it will cure the bluescreen problem...So i'm waiting for input on that.
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Old Feb 07, 2012, 05:19 PM
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Yep that's the plan, but the big unknown is if it will cure the bluescreen problem...So i'm waiting for input on that.
The Black/Blue screen is usually caused by loss of signal from the video receiver to the ground station screen. It could also be due to a loss of signal from the video transmitter on the plane to the video receiver on the ground station.

If you're getting a BSOD because the ground station video receiver loses battery power and shuts off, then yes, this should help prevent the BSOD if you land before the voltage to your receiver gets too low.

If you're getting a BSOD because of loss of signal from the video transmitter on your plane, then this will not help.

In any case, it would help by making you aware of your ground station receiver battery voltage! I like the idea
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Old Feb 07, 2012, 05:41 PM
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The question is would this solution help the lcd to handle weaker levels of video signal coming from the video receiver, what do you think?
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Old Feb 07, 2012, 05:48 PM
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The question is would this solution help the lcd to handle weaker levels of video signal coming from the video receiver, what do you think?
I suppose it could help because the arduino would be injecting data onto the video signal that's coming in...but on the flip side of that, if the video signal is too weak, the arduino wouldn't be able to identify a new frame of video and thus, wouldn't be able to inject the data.

Maybe Dennis could give a more definitive answer to this
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