Hi Erhard,
I am primarily a flyer who has learned enough about the RC products I use so that I can limit my mistakes.
I do not know how to measure the RF output power of a spread spectrum frequency hopping signal. It's a good thing Jim Drew does and I trust that the XPS products work well as required for our RC hobby.
More than a decade ago Jim Drew produced a product called the DivBee. The DivBee is a 2.4GHz transceiver module intended to be integrated by other manufacturers into their products that need wireless communications. The data sheet, which I found informative, has a table 5.1 that summarizes the RF power and duty cycle for the range of frequencies used in the 2.4GHz band. I found the data sheet by looking at the website: www.divbee.net
I think similar technology as used in the DivBee may be also used in the XPS RFU receiver. Also, at some point Jim said he was investigating using RFU-like components as a possible replacement for new XPS transmitter modules (in light of the fact that many of the original components are no longer available).
With ELRS the transmitter RF power can be set anywhere from 10mw to 1watt (!). So far I have been using 50mw and that gives adequate range. I don't know how it is FCC legal to transmit more than 100mw (including the antenna gain) in the ISM band.
Paul
p.s. Nice transmitter stick extensions. I have some of those rubber tips and I will try that out. Thanks for sharing that.
I am primarily a flyer who has learned enough about the RC products I use so that I can limit my mistakes.
I do not know how to measure the RF output power of a spread spectrum frequency hopping signal. It's a good thing Jim Drew does and I trust that the XPS products work well as required for our RC hobby.
More than a decade ago Jim Drew produced a product called the DivBee. The DivBee is a 2.4GHz transceiver module intended to be integrated by other manufacturers into their products that need wireless communications. The data sheet, which I found informative, has a table 5.1 that summarizes the RF power and duty cycle for the range of frequencies used in the 2.4GHz band. I found the data sheet by looking at the website: www.divbee.net
I think similar technology as used in the DivBee may be also used in the XPS RFU receiver. Also, at some point Jim said he was investigating using RFU-like components as a possible replacement for new XPS transmitter modules (in light of the fact that many of the original components are no longer available).
With ELRS the transmitter RF power can be set anywhere from 10mw to 1watt (!). So far I have been using 50mw and that gives adequate range. I don't know how it is FCC legal to transmit more than 100mw (including the antenna gain) in the ISM band.
Paul
p.s. Nice transmitter stick extensions. I have some of those rubber tips and I will try that out. Thanks for sharing that.