Hopeing someone can offer some insight in what is going on as it is really making me not want to fly this model. I have searched pretty extensively online and can't find anybody with similiar issues. The Minim OSD has never worked properly for me at all and this issue I get is that I lose the overlay during flight but the video feed stays unnaffected. I assumed a faulty Minim Board but ordered a second one that is also exhibiting the same issues. I only seem to lose the overlay with aggressive flying if I just plug the quad in and let it sit on the ground in with the props spinning it wont cut out. Also if i just put it in loiter and let it chill out the display will stay. If I reboot the system(unplug the battery and plug it back in) the minim boots up normaly and seems to work till I take off and then will randomly cut out again at a random time.
Like I said I assumed it was a faulty board so I ordered a second board (both were the v1.1 boards from HK) With the second board I did manage to do 2 full fpv flights with no issues but last night I took it out and about 4min into the flight I lost the overlay after some spirited flying. So I landed and rebooted the quad the display was back and tryed another flight right away I gave it a pretty good bump of throttle to get some altitude quickly and right as i did the display cut out.
I'm thinking now after seeing that it is either a voltage sag problem or interferance but what exactly is it effecting? Other thing I was thinking and hope someone can confirm is that when i got my first minim board i didnt come with cables so i ordered a ebay one. the connector didnt seem to fit perfectly in the telem port on the apm but It was working so I used it. I'm wondering if it is intermittently losing connection. How does the minim board react if the telem port gets disconnected while in use?
My second board from hobbyking did come with a cable but it has the wrong connector to plug into the apm port so I'm still using the same first original ebay cable with the second minim board.
This quad is a pretty standard build with commonly used components.
Discovery Clone Frame
APM 2.7 with gps/mag on a mast.
Afro 30A ESC Sunnysky 2212 980kv W/10" props
4000mah 3S battery
wire harness/power distro is all home made.
Minim OSD is hooked up exactly like this http://arducam-osd.googlecode.com/sv...maMinimOSD.jpg I have the board wired up with the sides seperate (5v from apm and 12v from the battery with no solder bridges on the board)
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Well I went right back at it and did as I said in my previous post and removed the 12V from the minim board soldered the bridges on both sides. and everything is now powered from the external BEC.
It is extremely windy right now so I cant do a real proper test flight but I did do some LOS. I did at least 5 throttle bumps from a hover to 90%+ and then another 5 throttle bumps from resting on the ground at idle to 100% throttle. The overlay was still there after when I checked the goggles so it seems I am making progress if not solved my issue, but untill futher testing I don't want to make that claim.
Here is how I ended up hooking it up but im wondering if I could go back and use the internal .5A bec built into the ESC so I can shed the extra weight. Thoughts?
I'm assuming you only have the sbec powering the apm and not a power module then?
Do you have any video picture issues not having the ground cable looped from the camera to osd to vtx?
The way I suggested is close to the picture but what I meant is the red and black wires from the apm to the osd need to be removed and instead they connect an sbec to the osd.
Then you have an additional sbec or power module to power the apm independently of the osd.
Your assumption is correct I still have JP1 installed and the SBEC is now powering the apm (which in turn powers the minim and the GPS puck)
I was originally concerned with not using a ground on the analog side of the osd, but because of how I had the connectors it was too easy to just jump them together and figured it was worth a try before having to make essentially a new harness.
I understand how you suggested for me to hook it up but that would of required me to really modify the wiring harness so I took the easy route and hooked it up as per my diagram above.
So far there seems to be no issue but like I said I really haven't done to much additional testing but on the ground with the motors at idle i'm having no issues at all and like I said when I did my los flight earlier I still had the Overlay when I checked the goggles after which would of not happened when I was using the minim with both sides fed(5v and 12v)
Once this insane wind dies down I will test it with a true FPV flight and see what the overlay/video is doing during actual flight.
My but this OSD has proved to be a pain! The Skylark Tiny OSD is much simpler to get up and running....
However, having persisted with the Minim, and thanks to all the clever people on this forum, I seem to have the thing working. I also had issues with the overlay when powering the two ends separately. Nothing.
So I soldered the relevant pads and tried powering the thing via the APM with the module. Fine at idle but rubbish in flight with only flashing telemetry. Have now powered the Minim with a 5v UBEC, disconnecting the ground and 5v from the Telemetry port on the APM. Seems to have done the trick. Thanks everybody!
I am having similar problems with my HK MinimOSD dropping out during flight, i have currently got it set up as shown on the minimosd wiki, Digital side gets its power from APM Telemetry port, Analog side gets its power from seperate 3s battery,Which also powers Immersion 25mW TX, DYS 3 axis Gimbal with AlexMos & a 5v BEC which will power a GoPro, The feed from the battery is split up to each device "upstream" of the MinimOSD & there is nothing connected to the MinimOSD 12v out.
The APM is powered with a HK Power Module (3dr clone), but i am about to replace it with the HK combined power module & distribution board.
I am looking at the advice which suggests replacing the 5v & gnd from the APM with one from a BEC. would it be possible to use the BEC which is attached to the 12v side or would i need a seperate one sharing a common gnd with the APM, the way i understand it, if i were to supply 5v & gnd from the "video" battery i would no longer have a GND reference for the APM signal wire, in effect it would be left floating, which i would see as an issue.
My other thought is to bring power from the ESC's BEC, i have the JP1 jumper removed so i was thinking of adding an extra servo wire to one of the spare channels and pulling the power from that, this way the whole digital side has a common GND independent of the Analog side GND.
i had also problem with minim osd it gets too hot on 5v and loose data on sudden power up. i tried with reduced voltage to board about 3.6v by putting 2 diodes in series the problem is bit solved but not completely. what i figure the the china assembled osd has component quality issue the chip seems to be 3.3v but operating it on 5v is making it hot.
This has been covered before -http://diydrones.com/forum/topics/minimosd-stops-overlaying-data?id...
But as the others have said its a voltage issue.
Solder the two sides of the minimosd together, keep the apm-minimosd data connection, loop the video signal and ground feeds only through the minimosd and supply power to it from a dedicated ubec/sbec set to 5v.
Its what I've had to do and has worked perfectly for some time now.
Well I'm still not having a lot of success. I was originally concerned that the internal .5A bec built into my ESC (that was powering all the 5v)was browning out so I installed a 5v/3A SBEC I had laying around and pulled the power wire off my ESC connector so its solely powered off the external SBEC that should have more than enough capacity.
After doing this I would say the problem only got even worse. It now cuts out as soon as I pretty much go over hover throttle amount.
I guess the next step is going to be to pull the 12V feed off the minim board and solder the bridges to power both sides from the same 5v source (no longer using the regulator built into the minim board)
If that still doesn't work for me I guess the next step would to be power the apm/gps off the esc bec and wire the apm to be powered solely by the SBEC as mark recommended.
Any input or a suggestion on a better course of action to follow?
The minimOSD is very sensitive to voltage fluctuations in both of its supply voltages. You're getting voltage glitches (probably on the 5V side) which take its voltage too low. If you drive the power to the MinimOSD from a clean 5.5V supply your problem will go away.
If you measure the 5V rail on the MinimOSD, you'll probably see that it's below 5V when the system is idle. When your motors pull a bunch of current it probably sags lower which glitches the MinimOSD into that "blank" state.
well I've had a little bit of success narrowing down the issue but I'm still unsure of how to proceed. The cable is definetly not my issue. I can make the board malfunction (overlay disappears) by giving it a good bump in throttle. I can also get the overlay to come back by just hitting the reset button on the board and it reboots no problem but as soon as i jab the throttle it goes away again. As long as i don't have any sudden throttle increases the overlay stays.
The board is really buried in the frame and takes about 1hr to disassemble everything to get at it so im really hopeing someone has a suggestion. I think I may remove minim and solder the bridges and remove the 12v feed and power it solely off the apm's 5v.
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