Jump to content

Attention: RC-CAM.com will be closing down August 2021.

The RC-Cam.com forum was the very first online community dedicated to the advancement of wireless video cameras on radio controlled (R/C) models. This is now called "FPV" (First Person View). We are proud of the contributions that our members have made to the FPV hobby.

We've seen significant changes over the last twenty years. Initially there were a lot of eager R/C hobbyist that built their own video systems. Allowing these creative individuals to share their work was the purpose of this site. Now the FPV market is flooded with low cost systems; Sadly DiY FPV video projects are now rarely discussed.

RC-CAM.com (main site and forum) will be closing down August 2021. This was announced several months ago (March 2021) to allow our members ample time to download any information that is important to them. After the site is shutdown the information will no longer be available here.

We appreciate every member's involvement with advancing the FPV hobby. It is indeed sad to say goodbye to all our online friends. Be safe and stay healthy.



Mesure vidéo signal?


Recommended Posts

For accurate measurements you need an oscilloscope with an analog bandwidth at least five times the measured signal bandwidth. NTSC and PAL video is about 5MHz, so the scope should be rated for 25MHz or higher bandwidth.

I use a TEK2445 analog scope that is 100MHz with TV Sync capabilities. But I've done it with a cheap digital scope that had about 1MHz bandwidth. The results were suitable for crude video signal level calibration.
https://www.rc-cam.com/forum/index.php?/topic/2825-using-the-50-digital-scope-to-measure-video-levels/

If your main goal is to calibrate FPV composite video, then there is a low cost ($20 USD) DiY solution that is very accurate.
https://www.rc-cam.com/forum/index.php?/topic/4126-diy-fpv-video-calibration-tool-low-cost/

 

Link to comment
Share on other sites

Most of the details to the video signal are lost with a 1MHz scope. But in my experiment, the bottom of V-Sync and peak white amplitude were present, so a crude measurement was possible.

Don't purposely purchase a cheap digital scope if you intend to do video measurements. But if you already own it, then try this: First use it to observe a good (calibrated) NTSC or PAL video signal. If the 1Vpp amplitude measurement appears valid then you will have confidence that it can be used to measure/calibrate a bad video signal.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...