Do you know the Nac for Jax?
Florida Forest Service
- Thread starter wcu02mpa
- Start date
-
- Tags
- brush fire dof forestry
Nac 046 was reported I haven't heard anything at my location yet. Just loaded it in yesterday!
Reelfishguy
Member
- Joined
- May 30, 2011
- Messages
- 83
It appears that District 7 repeaters all transmit out the same NAC 070 decimal. The repeater inputs would be 070, 071 etc. decimal. Similarly they just changed the input PL tone when they were analog
I'm confused/not following this... help me understand please.
Sounds like you are commenting that on a single frequency (159.405) you are hearing multiple talkgroups (TG 1, TG 160, TG 161, TG 162 etc).
Maybe the single frequency is using a different/unique NAC for each talkgroup?
How does that work/how do you program that?
Thanks
TG 1 is the Dist Disp for each District.
TG 160-164 is for Dist 16 Each TG is for which repeater location. Also the wiki has been updated for each TG Districts.
TG 160 Okeechobee
TG 161 Sebring
TG 162 Palmdale
TG 164 Stuart
TG 165 Vero
902
Member
There are a few things going on here that can be confusing...
First, NAC can be both decimal and hex. Some radios take a decimal, some radios take hex. To convert between the two, open the calculator on your computer, select the Programmer option, then enter the value in the right place. So, 46 was mentioned. Put 46 into the hex field and you'll see 70 in the decimal. To avoid confusion, radio programmers usually write the hex value with a dollar sign before it, so if you see $048, you'll know it's a hex value.
There can be a bunch of repeaters at different sites. These repeaters talk out on the same frequency. Some districts had more than one pair of repeater frequencies. When they were analog, they would use the same CTCSS tone on the output for all of the repeaters. The input was a different CTCSS tone. So, when they were converted to digital-only, the outputs became the channel number of the lead repeater. The inputs were the channel number of the individual repeater.
Here's a made-up example:
Swampy District, District 20, has 4 VHF repeaters. They operated analog on channels 200, 201, 202, and 203. Remember, this is a made-up example. All of the repeaters used to use 118.8 Hz CTCSS output, but had different input CTCSS tones that were unique to the repeater being used.
To listen to that district, you put in the transmit frequency of the repeater, and the decimal NAC of 200. A radio with a hex NAC would use $0CB as the talk-out NAC. You would only put in the NAC of the lowest channel used. So, for channels 200, 201, 202, and 203, only use 200 (which is $0CB in hex).
The repeaters more than likely use the channel number for their input NAC.
So, the hypothetical repeaters are NAC 200 for Ch. 200 talk-in, NAC 201 for Ch. 201 talk-in, and so on. That also means NAC $0CB for Ch. 200 and NAC $0CC for Ch. 201, and so on. Reminder, this is a made-up system just for illustration purposes, and inputs are not important for monitoring. The 200 series channels are analog-only in real life.
Since the repeaters all transmit on the same frequency and use the same NAC code so the radios don't have to be in scan and can hear whatever uses the same NAC so as to not step on anyone or miss traffic, how does a duty officer ("dispatcher") know which repeater to answer the unit that called on? This is important because the units in a district might be 70 miles apart and can't hear the other repeater, so the duty officer answering on the wrong repeater would be a problem for field units. Each repeater output is programmed with the talkgroup of the repeater being used. So, channel 200 would be TG 200 (because talkgroups are written in decimal), channel 201 would be TG 201, and so on. The screen would show which repeater was last used so the duty officer could speak with the unit over the proper repeater.
Hope that's less confusing.
First, NAC can be both decimal and hex. Some radios take a decimal, some radios take hex. To convert between the two, open the calculator on your computer, select the Programmer option, then enter the value in the right place. So, 46 was mentioned. Put 46 into the hex field and you'll see 70 in the decimal. To avoid confusion, radio programmers usually write the hex value with a dollar sign before it, so if you see $048, you'll know it's a hex value.
There can be a bunch of repeaters at different sites. These repeaters talk out on the same frequency. Some districts had more than one pair of repeater frequencies. When they were analog, they would use the same CTCSS tone on the output for all of the repeaters. The input was a different CTCSS tone. So, when they were converted to digital-only, the outputs became the channel number of the lead repeater. The inputs were the channel number of the individual repeater.
Here's a made-up example:
Swampy District, District 20, has 4 VHF repeaters. They operated analog on channels 200, 201, 202, and 203. Remember, this is a made-up example. All of the repeaters used to use 118.8 Hz CTCSS output, but had different input CTCSS tones that were unique to the repeater being used.
To listen to that district, you put in the transmit frequency of the repeater, and the decimal NAC of 200. A radio with a hex NAC would use $0CB as the talk-out NAC. You would only put in the NAC of the lowest channel used. So, for channels 200, 201, 202, and 203, only use 200 (which is $0CB in hex).
The repeaters more than likely use the channel number for their input NAC.
So, the hypothetical repeaters are NAC 200 for Ch. 200 talk-in, NAC 201 for Ch. 201 talk-in, and so on. That also means NAC $0CB for Ch. 200 and NAC $0CC for Ch. 201, and so on. Reminder, this is a made-up system just for illustration purposes, and inputs are not important for monitoring. The 200 series channels are analog-only in real life.
Since the repeaters all transmit on the same frequency and use the same NAC code so the radios don't have to be in scan and can hear whatever uses the same NAC so as to not step on anyone or miss traffic, how does a duty officer ("dispatcher") know which repeater to answer the unit that called on? This is important because the units in a district might be 70 miles apart and can't hear the other repeater, so the duty officer answering on the wrong repeater would be a problem for field units. Each repeater output is programmed with the talkgroup of the repeater being used. So, channel 200 would be TG 200 (because talkgroups are written in decimal), channel 201 would be TG 201, and so on. The screen would show which repeater was last used so the duty officer could speak with the unit over the proper repeater.
Hope that's less confusing.
I finally got around to scanning District 1 Blackwater and District 2 Chopola River Forestry Center. They have both switched over to P25. I have updated the database.
KF6DGN
Member
Yes, I heard that too, unfortunately.
Theradioman10
Member
What tac channels should be monitored? I see 190 to 259.
