MARCS - offset for tower output vs. input frequency

[dizwiz]

Hello

What is the offset in the input (vs. output) frequency on MARCS system?

Is it 30 Mhz ? or something different?

Is it the same for both 700 and 800 systems? or does 700 have a different offset vs 800?

Trying to get a better understanding of what frequencies being used (yes I know to program the output frequency).

 

[kf8yk]

Mobiles transmit 30 MHz higher than the repeater frequency for 700 MHz pairs, 45 MHz lower for 800 MHz pairs.

 

[nd5y]

746-776 MHz has +30 MHz offset.
851-896 MHz has -45 MHz offset.

Offset - The RadioReference Wiki

wiki.radioreference.com

 

[nd5y]

746-776 MHz has +30 MHz offset.
851-896 MHz has -45 MHz offset.

I should have added yesterday that those offsets are used everywhere in the US and Canada, not just on the MARCS system.

 

[dizwiz]

Thank you ! Helps my understanding of how the system works

 

[IAmSixNine]

You really dont need to know the offsets in order to know how a system works.
But you do need to know them to program a radio. So please be careful.

 

[mcjones2013]

You really dont need to know the offsets in order to know how a system works.
But you do need to know them to program a radio. So please be careful.

Just to play devil's advocate, having the input frequencies programmed in conventionally in a scanner is good if you are near an active incident but the scanner is not hearing the repeaters, you can switch over to the input frequencies to listen in. Obviously, you'd have to be fairly close to the incident to hear.