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Mr.RC-Cam

Next Generation A/P Camera Controller

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Hi Everyone,

I was finally able to get a sucessful flight :D

The video is here

As you will be able to see the Inspire reported glitches although I didn't

see it in the planes flight, but it does show me that I need to change

something to avoid a problem which I think is a great help.

The rx was in the back of a truck so that I could plug-in a vcr, so

the video had few dropouts. Everything that I put to use in the Inspire

worked perfectly :D I'm going to connect the RSSI and sound next. The plane is a

stick 40 with an O.S. 52-4-stoke. For my first ever video the Inspire is a fun and

very worthwhile addition to my plane :D I really like all of the features and the

flexability it has!

Thank-you Mr. Rc-Cam!

Midwest-flyer

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Thanks for posting the video. Very nice indeed.

I think it will be interesting to see the RSSI values when the glitches occur. BTW, did the glitch counting happen at about the same locations in your flying circuit? What is the distance you achieve in your ground range tests?

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Hi Mr. RcCam,

I will look at the video more closely to see if there is a pattern

with the glicthes and report back. Thanks for the insight!

I had 60 yds. with the antenna down without glitches so I

thought everything should be good to go. I will be opening up

my Jr rx so that I can see what chip it has. I had waited so that

I could maybe do my first flight sooner ;)

Midwest-Flyer

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Hi,

When I looked at the video the glitches seemed to happen

when the plane was going straight away or when finishing

the turn on its way back. So thats when the antennas are

parallel to each other.

And it looks like I'm going to need a different rx, none of

the IC # matched the #'s on the list of usable candidates.

Right now I have the JR R700, any ideas of a substitute?

Midwest-Flyer

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The 4017 is the servo signal decoder. So the FM Demod IC would be the other chip. However, 3390B87 appears to be a date/lot code. What other numbers are on it?

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Maybe we can work this backwards. How many pins does the chip have? Where is Gnd connected?

EDIT: My gut feeling is that the 3390B87 is a LM339 comparitor IC. If that is true, then there will be another IC on the board. Most likely on the other side. Try tracing the IF filter transformers to see where they end up at. Eventually they will connect to a FM Demod IC.

Edited by Mr.RC-Cam

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One of the pins would be connected directly to battery ground. Check again.

However, I think it is a LM339. There is another IC on the board. Obviously hiding.

Edited by Mr.RC-Cam

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There was another chip on the other side with an electrolytic glued on

top it has a # of 31136

041 as how it reads on the chip and it is a 16 pin.

there is still a lot of glue on the pins so it may take a little time to find the Gnd.

Midwest-Flyer

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The data sheet is here: http://pdf1.alldatasheet.co.kr/datasheet-p...BA/TA31136.html

RSSI is pin 12. There is often a outboard cap that you can solder to. Your voltmeter should be able to confirm that this pin has a voltage that is relative to the RF signal strength from the R/C Tx. What voltage do you get for (1) Tx Off and (2) Tx On, 5 feet away?

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That is a good sign, but the voltages are much lower than expected. Typically they would range from about .5V to 2.0V. Are there any external parts connected to the Pin?

EDIT: If pin-12 has no other components connected to it than that would be ideal. But, you will need to add a small cap across your meter leads. Perhaps 0.1uF or so. If there are other parts on the pin then do your best to draw a schematic and post it.

Edited by Mr.RC-Cam

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Perhaps the best thing to do is to hook up the RSSI to Gecko. Set it up so that it displays the RSSI voltage (not the bar graph).

Fully collapse the R/C Tx antenna like you would do for a ground range test. Start with the R/C Tx within a foot of the Rx. While watching the displayed voltage, slowly move away. While moving away, slowly change the orientation of the Tx antenna.

[1] What was the highest voltage? [2] What was the most common (nominal) voltage? [3] What was the voltage at the point where the servos began to twitch (end of range)?

With this information we can determine the best RSSI profile setting to use for your Rx.

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I still have alot of glue around the pins of the chip and it doesn't

come off very well, so it will take a little time so that I can solder to it.

I will try to be connected up to the Gecko sometime this weekend.

Thanks

Midwest-Flyer

April 18 I'm still working on removing the glue so I can solder :( M-F

Edited by Midwest-Flyer

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I still have alot of glue around the pins of the chip and it doesn't

come off very well

Once you get past the glue it will hopefully be smoother sailing.

A beta user found a GPS related bug (heading data would sometimes be goofy). I am very surprised that it was the only s/w bug (at least that I can recall) that the project has encountered so far. Especially since the embedded code has grown to about 30K. BTW, some new features were folded into the software, thanks to the helpful comments. I don't expect it will have everything everyone wants, but I do expect it will blow away a few folks. Or so I hope. :)

I froze the hardware design and went for one more PCB spin (now at Rev D). The latest board has some minor tweaks and does not impact the software. This is the version that will go into production. A photo is below. I expect to introduce the board sometime around June (+/-). I have a lot to do before then, including some new software features I think I might add (or they will come later if need be). High on the list is PAL video support.

By the way, I have transitioned away from the internal engineering project name (Gecko). The OSD's name is officially "Inspire." A web site for the Inspire, as well as the low cost Vizion OSD, is slowly coming online.

Beta testers: please keep the comments and feedback coming. I'll open a new discussion in the commercial vendor area shortly before the OSD product is released.

inspire2.jpg

Edited by Mr.RC-Cam

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I have had a lot going on since returning from my vacation, not much extra time for continuing my testing. I have installed the electromagnetic shield that Mr.RC-Cam sent me. (Thank you) I have also started the process of shortening up some of the extra wiring I have on the wireless video system. So far I have removed 13 inches of extra wire with some more to go.

I have ordered a new Archos AV-500 Pocket Video Recorder with a 30 gig hard drive to replace my Sony camcorder to record the movies. Quality should be much better than converting from VHS tape for posting the movies for downloads. By the way, the link to the test flight of the OSD board is up and running and has been for a while. I posted it a 3rd time on Putfile while I was in Mexico at an Internet cafe and it stayed there this time.

Mr.RC-Cam, the photo of the new production model really looks good. I like the way it will be covered on both sides to help protect the innards without adding much weight.

Zeek

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Zeek, the OSD's EMI/RFI noise is caused by the MAX202 RS-232 IC, which is near the 4-pin header at the bottom of the board. The noise is radiated, rather than conductive. A simple effective solution is to keep the OSD's internal wiring away from the MAX202 area, and route the R/C wiring, especially the Rx and its antenna, as far from the OSD as possible. Long wiring only invites EMI/RFI, so your efforts to shorten the cables should help out.

BTW, did I contact you about the PIC upgrade that fixes the heading error? If not, PM me and we can work it out.

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I have been testing the beta board for a quite a while but just came up with a capture card to get some video.

The first video is poor quality(signal problems) but I decided to post it because it shows the battery alerts in action. The supply battery for the Gecko ran out of juice and then the motor battery dipped below the threshold I set and that also triggered an alert (I am still trying to come up with an appropriate level for this trigger). The video source was a nikon 8400 camera so the black screen and the hour glass every once in a while is what happens when the camera takes a picture. This setup uses a servo to trigger the shutter.

The second video is from the new home of the osd board B) . I remounted it on a different camera mount which has a canon rebel SLR. This uses a small video camera that is aimed through the camera's viewfinder so the black squares with the dots are the focus points. I utilized an electronic shutter release so you can take pictures just about as fast as you can click the switch :P . I decided to give the OSD board it's own battery pack and then shared battery pack for the video transmitter with the camera mount's receiver.

The third video is more from the SLR mount from takeoff to landing.

I have also posted a few pictures.

Hopefully you don't get queasy watching the second video, I was playing with the camera tilt a little much!!

Click here for the video and pics.

I agree with Zeek, the new board looks awesome!! Great work Mr.Rc-Cam!! :D

Midwest-Aerial

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Did my first beta test. Noticed some glitching. Now I am trying to figure out how to get rid of it. As I understand it, there are three main things we can do. Besides the following, is there anything else I can try?

1) Make wires as short as possible

2) Move Rx as fas as possible from OSD, esp away from the MAX202 area

3) Put the OSD in a faraday type cage

Thanks,

-dave

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Midwest-aerial, thanks for sharing the photos and videos. Very nice job.

dalbert02, I believe I included a metal shield with your OSD board (if not, I can make you one). It is effective and eliminates the need for a full Farady cage. BTW, have you confirmed the glitching is from the OSD and not something else? For example, EMI/RFI from the motor's ESC, the video Tx, or camera, can be coupled to the OSD (because it is connected to everything), then to other places. It is often helpful to isolate where the actual source is.

2) Move Rx as far as possible from OSD, esp away from the MAX202 area

Keep ALL the video gear away from the R/C gear. Especially the R/C receiver and its antenna. From what I have experienced, simple physical separation goes a long ways in eliminating the problem. Ground range tests are the best way to test for problems.

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