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Poor Wireless Video Range. Blame the transmitter?


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#1 Mr.RC-Cam

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Posted 02 November 2009 - 02:19 PM

I receive a number of help requests from folks that say they are getting poor wireless video range from their transmitter. Despite the reality that such complaints can be caused be an endless number of things, the user immediately blames the transmitter.

A bit of detective work is needed before blaming anything. The main thing to do is to narrow down the source of the problem. I find it easiest to define the problem first, then move on to a plan of action. So, here are the three main categories that I use to classify a wireless video range problem:

(1) A low RF signal symptom is seen as fuzzy/noisy images that slowly grow more fuzzy as you move further away.

(2) Multipathing interference is a decent looking image that intermittently cuts in and out in a dramatic fashion.

(3) External EMI/RFI, audio/mic, and power supply induced interference is usually visual lines (or bands of noise) in the image that may be present all the time and/or vary during use.


It certainly gets more difficult when two or more categories are affecting the installation. If in doubt about where your problems are coming from then post a video that demonstrates the issue so that the experts can help you identify it. Providing clear photos of your ground station while in-use (so we can see how your antennas are setup), and good closeups of the video transmitter's installation, will usually help too.

Please use this discussion to share tips on solving range problems. However, if you need help solving yours then post a new forum discussion about your range problem.
- Thomas

#2 dalbert02

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Posted 17 December 2010 - 04:08 AM

I recently had a very difficult time with my system. I had very poor video at less than 50 feet using a 500mW lawmate Tx and I Tri-diversity system for the Rx composed of (1) Peak Antennas Colinear and (2) HyperLink 8db circular polarized patches. After serveral days of fumbling with ferite cores, grounding, voltage isolation, filters, etc. I am embarrassed to say that only then did I swap the antenna. Although it seems obvious now, that is probably one of the first things I should have looked at. When I put the antenna on an analyzer, it had infinite SWR at my Tx frequency. Just because it worked in the past is no guarantee that it is still good. My point is, don't take anything for granted, check everything with tools or swap with a known working system.
-dave

#3 ActionDrone

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Posted 27 September 2013 - 07:50 PM

Another problem man people have is also when they fly with full carbon fiber frame. Especially when that frame has two or three layers and you put the antenna on above the frame. My solution was obvious and I just had my antenna bent down under the frame and I had better range. Or just don't use any carbon fiber frame for any long range fpv system.