choosing RF signal frequency
First of all, there are several other considerations to make before frequency selection. All these frequencies are considered part of the radio frequency (or RF) spectrum. As far as 2.4 ghz (or 2,400 megahertz) signals in motion- it’s a little hard to explain. When both points are stationary, you’ll generally have a crystal clear signal (depending, of course- on interference and barriers). As one or both of the points are in motion, there can be an unusually large amount of signal breakup. Unlike “snow” received from lower frequency units, you get momentary pops inbetween clear signals. Higher frequency signals are more directional by nature. By using the two receivers (one with built in omnidirectional antenna & the other with a high gain directional antenna), some normal interference will be stabilized.
Essentially, lower UHF frequencies like 434 and 900 megahertz are better for those applications where motion exists in one or both links (i.e. body worn or mobile applications). Lower frequencies also TEND to provide better barrier penetration. The audio / video quality is otherwise identical.
The TX-5 and TX-5A (434 MHz UHF) are both excellent transmitters- but 434 MHz can be a little tricky in the “real world”. The sensitivity of the receiver and the sensitivity- or gain ability of a properly tuned frequency antenna used will make all the difference in terms of the signal quality, barrier penetration and range performance. Expected video quality can range from marginal or even poor to excellent, depending on the quality of the tuner and antenna within the UHF band. *NOTE: Most consumer level VCRs and televisions are known for having weak built-in UHF band tuners. And high gain antennas (see below) are extremely hard to find tuned into this frequency range.
For that reason, most would-be users of UHF 434 are ideally recommended to use our 900 MHz with matching receiver instead. Again, however, lower frequency (900) units will provide a MUCH more stable signal than microwave links where transmitters and/ or receivers are in motion. For stationary links, low or high frequencies are of little consequence- but the higher powered higher frequency units are typically recommended as they tend to have directional antennas built in.
5.8GHz transmitters are the newest entry into the consumer and commercially available frequencies and have a couple of major advantanges going for them. First of all, there is not that much equipment out there using this frequency- and it’s not being used by all levels of consumer-level equipment. Also, you have a ten channel selection, allowing you to fairly easily avoid the rare signal(s) which may be close enough to cause a problem
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