Embedded Files
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Hardware problems and solutions
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OSD is hot
OSD during work can become hot - so for those flying in tropical countries or at warm summer - here is a very good and extremely effective and cheap cooling system .
Simple electrical copper wire 2,5mm or 2mm - soldered as on picture .
Wire can be exposed outside of canopy or can be screwed to something inside canopy of "flying device" .
In present time all units are already prepared with copper wire like on picture below , works well
When still hot, keep copper wire out of shrink, also consider to pierce copper wire out of canopy of plane. Copper is very soft, so you can made shape of this wire as you want.
Another alternative , a bit more complicate cooling systems done by users :
GPS antenna must be always up side
IMPORTANT GPS
Thermal plastic shrink on GPS module is very important to prevent it from any mechanical cable movement - without it , very easy cables will brake the connection pads and GPS will be useless - without plastic on GPS module , any scratch on GPS antenna will consequence as loosing receiving parameters of all module , so will case problems with sat receiving and position lock - also prevent against moisture in air but remember is not waterproof .
Plastic on GPS module is very important to keep it in good mechanical condition - never remove it .
GPS have long time for satellites lock
GPS module have about 30cm long cable to be placed far away from rest of electronic to avoid jamming and glitches sources like Video TX and sometime camera etc.
So be sure to place GPS module as far from other equipment as possible .
Usually the GPS problems are because GPS signal is jammed
Sometime by cameras powered by 5V (sometime 12V) cameras jamming by step-up DC/DC internal converters .
Sometime by bad quality of supply voltage .
Sometime by Video TX frequency interference (changing channel usually help) .
Sometime by metal parts near or under of GPS module somehow covering or suppressing signal (check if GPS is placed antenna to sky ) .
Sometime by other RC equipment .
Sometime by Sun activity, any Sun eruptions affect quality of GPS signal and unfortunate such eruptions are often .
Sometime by near placed GSM stations, working also near 900MHz and 1800MHz band .
To obtain what happened , the best way is to connect only OSD and GPS directly to any monitor or TV at open sky - then check satellites lock time . If still bad contact to me .
Then adding one by one rest of equipment (camera , video TX etc.) to see what is the jamming source .
Many confirmed cases of bad GPS working , was because of cameras jamming - changing for other camera type solved problem.
About the backup battery for GPS - I made some experiments and when the weather is bad , battery is not helping a much in satellites lock .
If weather conditions are good - battery help - keep 6 satellites after 5 seconds - but without battery GPS keep 7 satellites within 50 seconds in the same good conditions .
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Here is also very good tip for increasing GPS sensitivity , this was checked by users with success on many platforms as quadro , planes and others (even boat) .
We use aluminium tape or plate about 40x40mm , then place it under GPS module .
Alu plate is not grounded .
So , at platform where was a lot of jamming and glitches because of all electronic was packed in very small space as quadro , GPS hold only 4-5 satellites after some minutes , what is a very bad result .
Now it detect at could start about 7-8 satellites within one minute (about 40-50 seconds) .
That means , this modification rapidly improved GPS sensitivity and suppressed glitches .
Before mod :
After mod :
At plane :
HARDWARE PROBLEMS - NO OSD LAYOUT
Well , I must write few words about the possible hardware problems of OSD .
It is hard to believe but most returns for service/repairing are problem of simply changed Video system PAL-NTSC or opposite . Isn't it funny ? .
Losing time and money for delivery for reason of changed Video system , accidentally holding pressed too long red button on OSD .
This issue is fixed since 1.69 software version - when time of button hold for Video system change is 2 seconds (or more) - not one . I hope that this solve this funny problem .
NO POWER TO OSD
Another very seldom problem is burned diode 1n4148 at supply power input - to solve - measure voltage at GND and 12V pad - must be about 0,8V less than at power cord (red socket) . Simply replace the diode . In board v1.2 you can put bigger diode (minimelf shape) at bottom layer of board - there are pads for diode already designed .
NO POWER TO GPS
Another often serious returns for service/repair , is burned diode 1n4148 (bottom layer) at GPS power supply output . Some units had this because when someone playing with OSD and in any case will short or whatever put wrong to GPS pinout - this diode have to burn as diode is also the fuse (100mA limit) - when burned that is OK .
To check the situation please measure the voltage when GPS is connected at pins GND and Vcc (for GPS) - it must be around 4,2V - if it is less or zero so diode must be replaced to fix OSD unit (fix supply power for GPS module) . You can use any shape (1204 , minimelf etc.) diode 1n4148 or whatever similar Si diode .
The diode showed on picture providing power for GPS module , can be replaced by most users without problems .
NO ENG Voltage measurement
Another often problem is when at ENG input will be connected opposite side positive and negative voltage of Engine Battery when GND of both battery are connected (Main battery and Video battery have common GND) .
In this case always the Inductance is burned ant GND side of ENG input at v1.1 board or a small trace is burned at board v1.2 . It is OK - because they work as fuse - so that is normal in such case .
Solution - remove burned inductance - and use tiny wire to shortcut those two pads - reconnect pads on board to made connection .
Those GND pads circled red on picture .
If Main battery and Video battery have common GND , then positive ENG pin input is still works well - so not need any fixing .
USB cable broken
Problem of USB cables - it happened when tiny cables are broken near the black socket connector (to OSD side) - to solve this remove golden connector from black case and solder the cable with connector to restore connection .
Do not draw them out holding cable because will brake - but gently push them out using small screwdriver .
USB drivers installation problem Win7 32 64
Generally for Vista Win7 32 and 64 bit use drivers from 10. Downloads
Prolific use file Prolific_drv_XP_Vista_Win7_32_64bit.zip , this is also solution for Prolific (code 10) error in Win7
OTi use file OTI_USB_driver_Win7_64.zip
When you still have USB drivers installation problems under Vista or Win7 64bit - you can run virtual machine with installed regular winXP 32bit on your PC from Microsoft .
here is the link http://www.microsoft.com/windows/virtual-pc/default.aspx
Some of basic type Windows systems not allow to use those MS virtual machine , so you can use a very good virtual machine named VMware http://www.vmware.com/ - what in my opinion is very nice solution , allow to run any winXP , Linux or even MACOS on your PC .
That is general solution for any driver-software problems under 64bit Win systems .
Look at Free Products, VMPlayer is free http://www.vmware.com/products/player/overview.html
If still have problems - you can write to MS and ask them , why they made system not compatible with previous versions .
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Fortunate till now there are not any more serious damages of OSD units noticed . It is probably because of fuses described above .
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