Need suggestions for 72MHz freq scanner

[charles0198]

For the 50 channels of 72MHz band what is the best method to display the operational channel on a R/C frequency scanner? Could an LED for each channel (total of 50) be helpful or it should be an LCD display. One should easily check whether his channel of interest is operational (occupied by him or someone at the field).

An additional feature that I am considering is the time since the channel was operational so that it can be assured to safely fly.

Also what should be the technique of detecting the channel. Either an RF signal strength detection or a complete decoding of PPM or PCM signal but PCM decoding is a bit tough as each brand has it own proprietary coding scheme.

[Andy W]

My EVO has a scanner built-in. It checks if the channel is clear on powerup, and can also scan the entire frequency band. It shows relative signal strength as a bar-chart. None work real-time on all channels, they step thru them one by one.
..a

[JMP_blackfoot]

http://www.llm-electronic.com/download/model_scan_english.pdf

LLM makes a scanner which is widely used in France, even recommended by the French Modelling Federation.

[Mr.RC-CAM]

Could an LED for each channel (total of 50) be helpful or it should be an LCD display.
An LCD that shows ALL active channels, as well as those channels that have been active within a user defined time period.


Also what should be the technique of detecting the channel. Either an RF signal strength detection or a complete decoding of PPM or PCM signal...
Do not rely on the R/C decoding method that is used. Instead, just detect the presence of the RF carrier. That in itself is all that it takes to cause interference troubles.

The one problem with scanner designs is that they work best with stable RF sources. For us R/C'ers, there are RF interference events that are grossly sporadic or poorly defined. Scanners are blind to these sort of things. So, to help, I suggest you also include an audio montior so that the user can listen to a chosen R/C freq for signs of such trouble. The human ear does a fine job of detecting noise in a sea of RF mud.

RC-CAM

[hadihf]

PulseStar Receiver at http://mstar2k.com :)

[Acetronics]

Hi, Charles

Us, frenchies, have a special scanner for R/C bands ... it's made and sold by LLM ( Luc Lotteau Microélectronique )

www.llm-electronic.com/index

it's called " Model-Scan " ...and works well for ~ 200 Euros ...

Even canadians have it !!!

Alain

[lazy-b]

Charles: how's your Synthesize Receiver projects?.......I was thinking of using 50 pcs Super Bright LED, using only 15 I/O line in 10 Column by 5 Rows, to indicate the activities of each frequency........can use different blinking rate to indicate different status, i.e. Alway ON for active frequency, blinking has been active once for the pass hours.

Guys: I have an ICOM R1 portable scanner than can scan from 100Khz to 1.3Ghz....but when I set it to scan automatically from 72.010 to 72.990 at 10KHZ, it can scan and automatically Save the active frequency to memory. but the result is not accurate.....the scanner have difficulty identiflying active and in-active frequency. cause it sense those splatter as active frequency......so I usually use manual scanning thru the use of visual (Signal Strengh) and Audio.......Its difficult to use it, everytime I need check again, I have to scan it one more time.