Portable Radio Transmits But Dispatch Can’t Hear

[kkhudairi]

I’m using a Kenwood NX-1200 AVK that I programmed to use on duty with the ambulance service I work for. I’m available to receive transmissions from dispatch and I can hear myself on the radios of other units when I transmit, but it seems that dispatch can’t hear me as I get no response when I hail them. My service doesn’t use repeaters and I have the DCS tones programmed in normal direction for both Rx/Tx. Any ideas what the issue is?

 

[RFI-EMI-GUY]

You don't have the duplex (repeater offset) configured properly. You are stuck in simplex mode.

 

[AJAT]

My service doesn’t use repeaters

Are you sure you don’t use repeaters? If that is true your radio I am assuming a 5watt HT probably can not reach the dispatch. I would assume if you are on an ambulance service with a radio system designed to cover your town you have a repeater. Like rfi guy said sounds like an issue with the repeater setting you have programmed in your radio.

 

[kkhudairi]

Yes, I personally confirmed with our director of communications that our company does not use repeaters. We have portable radios that are able to communicate with dispatch so I’m not sure what I could be doing wrong. My only guess is the direction of the DCS but I don’t how to determine what it should be.

 

[RFI-EMI-GUY]

Yes, I personally confirmed with our director of communications that our company does not use repeaters. We have portable radios that are able to communicate with dispatch so I’m not sure what I could be doing wrong. My only guess is the direction of the DCS but I don’t how to determine what it should be.

You might not have repeaters, but still have duplex dispatch facilites. Look up the license and see if the mobiles (MO) are listed on a different frequency than the base (FBx). What is the call sign, kenneth?

 

[kkhudairi]

If that’s the case, would I program it like a regular offset?

Update: I just checked and the mobiles are on the same frequency as the FB.

 

[mmckenna]

Yes, I personally confirmed with our director of communications that our company does not use repeaters.

While you were talking to the "director of communications", did you think to ask them for the correct info you'd need to program your radio? They should have that info. It would make this a whole lot easier….

 

[mmckenna]

If that’s the case, would I program it like a regular offset?

Update: I just checked and the mobiles are on the same frequency as the FB.

OK, so simplex.
There are a couple of things that could be going on:

The mobile radios may have something set up like "off hook" tone settings. That is when the mic is off the hanger, it switches to carrier squelch mode. That would let them hear everything on the channel.

The system may be set up with 'split tones', where it uses one tone to transmit from the repeater, and another on one the RX side.

Your radio is not getting a good enough signal into the base station and they just cannot hear you.

 

[kkhudairi]

While you were talking to the "director of communications", did you think to ask them for the correct info you'd need to program your radio? They should have that info. It would make this a whole lot easier….

Unfortunately not. It was our first time meeting and I didn’t want to press for lots of detailed information.

 

[kkhudairi]

OK, so simplex.
There are a couple of things that could be going on:

The mobile radios may have something set up like "off hook" tone settings. That is when the mic is off the hanger, it switches to carrier squelch mode. That would let them hear everything on the channel.

The system may be set up with 'split tones', where it uses one tone to transmit from the repeater, and another on one the RX side.

Your radio is not getting a good enough signal into the base station and they just cannot hear you.

Could it just be that the radio is in duplex mode?

 

[stmills]

Are you verifying the frequencies from a radio, the systems FCC license or the Radio Reference database? Are you willing to share what call sign you are trying to connect to - someone on here may have some insight for you.

 

[kkhudairi]

Are you verifying the frequencies from a radio, the systems FCC license or the Radio Reference database? Are you willing to share what call sign you are trying to connect to - someone on here may have some insight for you.

From the FCC database: ULS License - Industrial/Business Pool, Conventional License - WQMF652 - Cataldo Ambulance Service Inc - Frequencies Summary

 

[AJAT]

FB2 is a repeater FCC Station Class Codes - The RadioReference Wiki

What frequency did you program?

While you were talking to the "director of communications", did you think to ask them for the correct info you'd need to program your radio?

This would be your best bet to get all the correct info. You can also reach out to the contact info on the license.

 

[AJAT]

It sounds like you programmed your radio to the output of the repeater. You can hear the repeater output, that is why you hear dispatch, you are transmitting on the output of the repeater, so any radio close to you will receive you, dispatch will not, since the repeater is not receiving your transmission and dispatch to to far to hear your low power HT without the repeater.

I would guess your repeater pair is 152.2850 and 153.9900. That is a guess. Is your director of communications your radio tech?

 

[RFI-EMI-GUY]

It sounds like you programmed your radio to the output of the repeater. You can hear the repeater output, that is why you hear dispatch, you are transmitting on the output of the repeater, so any radio close to you will receive you, dispatch will not, since the repeater is not receiving your transmission and dispatch to to far to hear your low power HT without the repeater.

I would guess your repeater pair is 152.2850 and 153.9900. That is a guess. Is your director of communications your radio tech?

Nope his input is one of the 157.xxx or 159.xxx MO frequencies. The location search on FCC ULS will sort of narrow it down, radius around location x.

Thats assuming that the system is properly constructed to the license. If you cannot ask the system manager (DOC) a direct question about programming a personal radio, likely you should not be putting a personal radio on the system...

 

[mmckenna]

Your company is also licensed for analog FM and DMR on those repeaters. Are you sure you've got all the correct information, because it sure seems like you are missing a lot of what you need.

In addition to knowing which repeaters are using which input frequencies, you also need to know what type of coded squelching is being used, as well as if they are using any sort of radio ID's.

I think you need to talk to the Communications Director and get this all in writing before you go much farther. You can chase these issues around all day long, but without correct info, you run the risk of causing interference, or your radio not working correctly when you really need it. Should not be difficult at all for the company to provide you with the info, or put you in touch with the person who does the radio programming. No part of programming radios on a public safety system should rely on a hobby website or leaving things up to chance. This sort of stuff is a big red flag to those of us that run these kinds of systems. It shouldn't be this hard if they want your radio on their system.

 

[AJAT]

Nope his input is one of the 157.xxx or 159.xxx MO frequencies.

That makes more sense. Input on the mobile frequencies.

 

[stmills]

Reviewing the license provided and the info linked it appears to me the channels are as follows- this was determined by matching dates of first use with the pairs:
152.9900/ 149.6600 Ch 1 Atlantic 1
152.2850/157.5450 Ch 5 Atlantic 4
I highly recommend you review your companies Radio Operations Policies - this is from the policy I found with a simple google search of Cataldo Ambulance frequencies- the bold is as written in the policy.
PROHIBITED USES OF RADIO COMMUNICATION SYSTEM(S)
1. FCC rules prohibit the use of any profane or indecent language on the radio.
2. Use of personal radio equipment mobile or portable not issued, programed or maintained by the Cataldo Ambulance Service is prohibited.
3. Personal messages unrelated to company business are prohibited, except emergency in nature
4. Do not reprimand over the air.
5. Do not click your microphone or make odd noises on the air.
Cataldo Radio Operations Policy
Cataldo Radio Users Guide
Scan New England Cataldo Info

 

[kkhudairi]

I’m receiving on 152.990 MO and to my understanding I should transmit to 152.990 FB2. I do have the correct squelch tones.

Thanks for all the help guys, I’ll be looking into these solutions.

 

[kkhudairi]

Reviewing the license provided and the info linked it appears to me the channels are as follows- this was determined by matching dates of first use with the pairs:
152.9900/ 149.6600 Ch 1 Atlantic 1
152.2850/157.5450 Ch 5 Atlantic 4
I highly recommend you review your companies Radio Operations Policies - this is from the policy I found with a simple google search of Cataldo Ambulance frequencies- the bold is as written in the policy.
PROHIBITED USES OF RADIO COMMUNICATION SYSTEM(S)
1. FCC rules prohibit the use of any profane or indecent language on the radio.
2. Use of personal radio equipment mobile or portable not issued, programed or maintained by the Cataldo Ambulance Service is prohibited.
3. Personal messages unrelated to company business are prohibited, except emergency in nature
4. Do not reprimand over the air.
5. Do not click your microphone or make odd noises on the air.
Cataldo Radio Operations Policy
Cataldo Radio Users Guide
Scan New England Cataldo Info

So you’re saying for Atlantic Ch 1, the Rx frequency is 152.990 and the Tx is 149.660?