Won't use FM mode? TRX1?

Thatsclear

Member
Joined
Oct 25, 2019
Messages
77
Location
ON MI OH NC
I am doing a "limit scan" for bands 137-144 MHz but when I do this the transmissions come through as AM not FM so I can't understand what is being said. How do I change to this FM?
 

Ubbe

Member
Joined
Sep 8, 2006
Messages
5,724
Location
Stockholm, Sweden
How do I change to this FM?
The US bandplan in the scanner are set to AM in the 138-144MHz range using a 12,5KHz step size. If you change to United Kingdom bandplan it will do FM but using a 6,25KHz stepsize, half the speed.

When you enter the limit values in the scanner and then push the menu button you should come to a sub menu where you set what type of analog or digital modes you would like to receive. I don't remember if it also had modulation and stepsize there as well. But I think it was one of Whistler scanners negative points that it strickly follows the bandplan and cannot be manually changed and needed the bandplan to be switched out to another countrys.

/Ubbe
 

jaspence

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Premium Subscriber
Joined
Mar 21, 2008
Messages
2,427
Location
Michigan
The first paragraph states that the military aircraft uses AM and gives the possible frequencies, including the range he asked about.

"Aircraft communications will be in AM mode while satellite communications in this band will be in NFM mode. Military aircraft sometimes also use the Civilian Aircraft Band (108 to 137 MHz), especially when flying into a civilian airport. They may also be heard in the 137 to 144 MHz..."
 

CycleSycho

Member
Joined
Jul 26, 2016
Messages
444
Location
Central South Carolina
The first paragraph states that the military aircraft uses AM and gives the possible frequencies, including the range he asked about.

"Aircraft communications will be in AM mode while satellite communications in this band will be in NFM mode. Military aircraft sometimes also use the Civilian Aircraft Band (108 to 137 MHz), especially when flying into a civilian airport. They may also be heard in the 137 to 144 MHz..."


:) Ahhh, learned something new today! :)


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