JT1000 NarrowBand?

[mr uhf]

Can a JT1000 work on the new 2.5KHZ channels? Any information would be appreciated.

[Will]

The JT1000, like its brother the HT1000 and the P/M1225, can be set for 12.5khz channel spacing and 2.5khz deviation and Rx bandwith on an per channel basis. In the RSS Per Channel select Channel Options and set to 12.5khz.
The only thing missing is the radio will not do the companding that some of the newer radios, like the HT750 series, do.

[mr uhf]

Thanks for the information. What is the advantage of companding? Can the MT2000s do 2.5?

On 2001-11-27 17:12, Will wrote:
The JT1000, like its brother the HT 1000 and the P/M1225, can be set for 12.5khz channel spacing and 2.5khz deviation and Rx bandwith on an per channel basis. In the RSS Per Channel select Channel Options and set to 12.5khz.
The only thing missing is the radio will not do the companding that some of the newer radios, like the HT750 series, do.

[Will]

Companding is short for compressing and expanding the audio to help overcome the extra noise at the narrower deviation settings. The Spectra 900's used the same thing but called it HearClear!
The transmit audio volume is compressed, and then the receiver expands the audio volume to bring it back to the same level.
If you have a deciant system using 2.5khz dev then you would not have to have the companding.
By the way, this is nothing new, it was used on the AM police transmitter in Pasadena in the 50's/60's. It helped greatly to over come static on the AM (amplitude modulation).

[raymond345]

I found on the 12.5 spacing with 2.5k
audio that when set to this and the other radios are on the old system that we had very poor audio.The rss defaults to 12.5 and u must look to change it or u are in trouble
using the radio.First time out missed it and cloned 23 radios with 12.5khz and boy did it cause fun. Now I look at rss closer.