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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 is being announced now (March 2021) so that everyone has 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.



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As a very rough guide measure the power going in and think maybe half is going to be your output power. There are lots of ways to measure RF, if you google it will give you many options. Why do you need to know?

Terry

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If you want a real measurement that is worth something (i.e. gives you info both about power and frequency accuracy), you'll have to find someone with access to a spectrum analyzer (which is a very expensive piece of equipment).

The output power vs input power doesn't say anything, from my experience output power can be anywhere between 1/2 to 1/5 of input power depending on design, and especially a TX that is defective or sends spurious everywhere (=bad quality) will still use the same input power.

Edited by Kilrah
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I bought video tx (1.3ghz) 800mw and another one 1500mw.

Is there any way to measure poweroutput is real ?

The cheapest most accurate way would be to find a 'ham' in your area with a bird or coaxial dynamics wattmeter and offer to buy him a 'slug' for the frequency and power you are using. Give him the slug for payment for borrowing his meter. If you are more diy you can rectify the rf feed into a 50 ohm dummy load and measure the voltage to calculate watts.

-dave

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I have a bird wattmeter which I use to test transmitters output. Unfortunately I only use the 900 Mhz

band and have no slug for 1.3. As the previous poster said if you would be willing to buy the slug I

could test all your units.

Yet a spectrum analyzer would be better as it would tell you RF energy radiated at your specific wanted

frequency versus a summation of all power out. My cheap USB spectrum analyzer only works in the 900 Mhz

band but has taught me volumes about transmitters I have purchased.

The bird wattmeter lets me match antennas to transmitters and see how transmitters are performing.

-Ken

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