Bandwidth of the 900MHz 500mW audio/video transmitter signal

[clebio]

I have the 900MHz 500mW audio/video transmitter and a GoPro camera. I do NOT have the OSD unit.

When I power up the transmitter by itself, I get a very nice, clean frequency range of a few MHz. However, when I plug the GoPro video cable into the transmitter, the transmission blasts all adjacent frequencies for tens of MHz on both sides of 910 (I'm in the USA). Switching the GoPro to PAL output does not seem to help.

I'm concerned that I'm interfering on other (HAM or amateur radio) frequency bands when this happens. How can I clean up the frequency emissions while keeping the GoPro live feed attached?

The received video (on the dual receiver) is fine, I'm just concerned about RFI for other operators.

 

[Martin Y]

Bandwidth of an FM video signal is 18 mhz, plus a few harmonics.

 

[clebio]

So if the transmitter is at 910MHz, and the bandwidth is 18MHz, roughly, then that's (910 - 9) = 901 and (910 + 9) = 919. The 33cm amateur band is 902 - 928 MHz, though, so on the low side of the band, this transmitter bleeds into the next allocation block (Land Mobile).

My handheld scanner can only scan the amateur bands, so that would explain why I can't see the fall-off, then.

 

[Alex Villa]

The power of the transmitter is very reduced, the adjacent band "land mobile" is cell phone. The signal leakage at that power cant cause any problem. Dont worry about.

 

[clebio]

That works. I won't worry about it. Thanks for the reply!

 

[CaptnKliegle]

Here's a typical plot:

From DPCAV.com