Scanning local ambulance question

[dae006]

Very new to this so my question my be laughable.

First let me show you the Radio Reference frequencies I programmed as well as my CHIRP program:

Radio Reference:
View attachment 172084

My Radio program (CHIRP):

View attachment 172085

The way I understand it is that Channel 55 is a simplex frequency and channel 59 is the same frequency but using a repeater with a +5 offset.?.?
The Dispatch for the ambulance is 45 miles away from me and the ambulance garage is 3 miles away.

Scenario this morning:
1). I hear the tone from dispatch (45 miles away) and hear the call on channel 55 (non-repeater channel) for the ambulance call. This does not make sense to me. I thought this would be using the repeater channel (59)
2). I hear the ambulance respond "In Route to scene" on channel 55
3). I DO NOT hear a response from dispatch with the "time out". Is this due to no tone to open repeater- this is where I know nothing about how this works.
4). I hear the ambulance respond "on scene" on channel 55
5). No dispatch response
6). I hear ambulance is in route to hospital on Channel 59, the repeater channel.?.?
7). Again, I do not hear a response from dispatch confirming the time leaving the scene to go to the hospital.

As you can see, I am scanning these channels. Are they actually transmitting over both channels and it just happened to pick the channel that was on the screen at the time of the transmission?

That being said, other than the original call from dispatch that used the tone, I never heard dispatch after that, is there a way to hear dispatches responses that I am currently not hearing?

 

[jtwalker]

For some reason your attachments are not visible (at least to me) and we have no idea on your location to look at the info you are using.

 

[Whiskey3JMC]

First let me show you the Radio Reference frequencies I programmed

Welcome to the RR forums. Please provide Radioreference database URLs or at least reply with your location and agency(ies) of interest so we can get eyes on the RRDB to see what is monitorable. I'm assuming you're using a TIDRADIO TD-H3 to try and monitor?

 

[WA0CBW]

I could not view them as well.
BB

 

[dae006]

Radio Reference:

My Radio Program (CHIRP):

Lets see if this works.

 

[dae006]

Welcome to the RR forums. Please provide Radioreference database URLs or at least reply with your location and agency(ies) of interest so we can get eyes on the RRDB to see what is monitorable. I'm assuming you're using a TIDRADIO TD-H3 to try and monitor?

Correct. I've re-posted my screen shots and am waiting for moderator approval.

 

[Whiskey3JMC]

Looks like Fillmore County, MN for those playing at home. Are you certain your "local ambulance" doesn't operate on ARMER?

If they do then your Tidradio won't trunk track nor does it handle P25 so you'll need one of these capable receivers. If you're not sure who operates where then you may want to click the Report link at the bottom of your opening post and ask for this thread to be moved to the Minnesota Discussion Forum where hopefully you'll find someone local who can point you in the right direction...

 

[bearcatrp]

I know the ambulances in st cloud area are on armer.

 

[stmills]

1.Filmore County is on the ARMER system. The vhf is for paging out oncall crews.
2. In your programming ch 55& ch 59 are both programmed to the same receive frequency- you have selected an offset of +5 which is not used in VHF - the transmit frequency into the repeater is different for each vhf repeater no standard offset. To listen to the repeater input you have to put that frequency into the receive frequency field.

 

[dae006]

stmills- Thanks for your reply, as I said this is all new to me. I thought the +5 offset would allow me to listen to their transmission. When you say "that frequency" needs to be put in the the receive frequency field, are you saying the 154.875000 in the RX DTCS field?? or 159.87500 (+5)? Or is this currently an unknown frequency?
Sorry for my lack of knowledge.

 

[wogggieee]

2. In your programming ch 55& ch 59 are both programmed to the same receive frequency- you have selected an offset of +5 which is not used in VHF - the transmit frequency into the repeater is different for each vhf repeater no standard offset. To listen to the repeater input you have to put that frequency into the receive frequency field.

I know you know this but just to point out for OP, the 5 mhz offset is meant for Amateur (ham) radio and only needed for transmitting.

 

[ecps92]

I know you know this but just to point out for OP, the 5 mhz offset is meant for Amateur (ham) radio and only needed for transmitting.

not for VHF, VHF amateur is +/- 600 khz , UHF is +/- 5 mhz (Amateur)

 

[dae006]

I thought GMRS used a +5 offset.?.?

 

[stmills]

stmills- Thanks for your reply, as I said this is all new to me. I thought the +5 offset would allow me to listen to their transmission. When you say "that frequency" needs to be put in the the receive frequency field, are you saying the 154.875000 in the RX DTCS field?? or 159.87500 (+5)? Or is this currently an unknown frequency?
Sorry for my lack of knowledge.

A few points for clarification:
1. You are working with a two way radio not a scanner
2. You should not be entering anything into fields that allow this radio to transmit on Public Safety Frequencies-which you are currently doing - you should be programming for Receive only.
The field “Frequency” is the frequency that the radio is receiving on.
Offset selects the frequency the radio transmits on.
+5 MHz offset is the standard for UHF amateur and business- but on amateur it can be +5 or -5
RX DTCS is filtering on the receiving frequency.

 

[ecps92]

I thought GMRS used a +5 offset.?.?

my reply was more of the disinformation for Amateur

Yes, if you want to get into all the nuances

GMRS is +5
UHF (450/460) is +5
UHF T-Band is +3
then we have 700, 800, 900 which are all in the wiki's if needed, but scanners don't need em'

 

[dae006]

A few points for clarification:
1. You are working with a two way radio not a scanner
2. You should not be entering anything into fields that allow this radio to transmit on Public Safety Frequencies-which you are currently doing - you should be programming for Receive only.
The field “Frequency” is the frequency that the radio is receiving on.
Offset selects the frequency the radio transmits on.
+5 MHz offset is the standard for UHF amateur and business- but on amateur it can be +5 or -5
RX DTCS is filtering on the receiving frequency.

2). Under Duplex I should have this turned off? Will do.

So back to my original question: Is there any way to hear dispatches responses? I only hear the initial page from them, but no responses after that. All I hear is the Fire/Ambulance transmissions

Thanks.

 

[stmills]

2). Under Duplex I should have this turned off? Will do.

So back to my original question: Is there any way to hear dispatches responses? I only hear the initial page from them, but no responses after that. All I hear is the Fire/Ambulance transmissions

Thanks.

You should have this set up as receive only - no simplex no duplex no offset
The best way to hear them is using a scanner that is listening to the ARMER system and the Talkgroups being used by these agencies. The VHF side is a patched feed for paging purposes- each agency does it differently on how much info is put out in the paging system.

 

[wogggieee]

not for VHF, VHF amateur is +/- 600 khz , UHF is +/- 5 mhz (Amateur)

Yes i know

 

[egftechman]

There is no "standard" repeater offset for VHF public safety and IB Pool
+5 MHZ is standard for 450/460 MHz, -45 MHz is standard for 850/860 MHz