Icom: How to make ICOM repeater mode support Air Band ?

[jamesbmwz]

I am a user of ICOM IC-2730A.

When I tried using repeater mode with UHF and VHF(left 438.000, right 145.100), it worked. Receive from right channel and transmit via left channel.

But it did not work on UHF and Air Band VHF (left 438.000, right 126.100).

Is there any way to enable repeater mode with air band and VHF?

 

[jeepsandradios]

Uh....You do know the radio wont transmit on the Air Band correct ? Not really sure what you are trying to do.

Transmit	144–148, 430–450MHz
Receive	118–174, 375–550MHz*1

 

[ecps92]

I am a user of ICOM IC-2730A.

When I tried using repeater mode with UHF and VHF(left 438.000, right 145.100), it worked. Receive from right channel and transmit via left channel.

But it did not work on UHF and Air Band VHF (left 438.000, right 126.100).

Is there any way to enable repeater mode with air band and VHF?

Airband (AM) is Simplex, no Repeaters or Duplex Operation

 

[tweiss3]

That is retransmitting between services, and the firmware is blocking crossband repeat from airband to UHF.

 

[prcguy]

That is retransmitting between services, and the firmware is blocking crossband repeat from airband to UHF.

I suspect the OP is trying to receive AM aircraft then retransmit to UHF to receive on a portable radio or similar, no tx on the airband. Some ham radios will do this, some maybe not. In the US if caught doing this it would be a violation of FCC part 97 rules. I wonder how the Chinese govt handles things like this?

 

[jamesbmwz]

That is retransmitting between services, and the firmware is blocking crossband repeat from airband to UHF.

Is there any way for unlocking this limitation?

Is there any way for unlocking this limitation?

I removed a diode to unlock Cross Band Repeater mode.

 

[AK9R]

The Air Band is AM, not FM. The radio can't transmit in AM. That's due to the design of the transmitter.

Since the radio cannot transmit in AM, it will not let you put the radio into cross-band repeat with one side of the radio configured for AM.

 

[prcguy]

The Air Band is AM, not FM. The radio can't transmit in AM. That's due to the design of the transmitter.

Since the radio cannot transmit in AM, it will not let you put the radio into cross-band repeat with one side of the radio configured for AM.

I have tested a lot of amateur radios unblocked, single, dual, tri, quad, and have never found one to transmit in the VHF air band using a MARS type mod, even though some had AM mode. That is done by radio mfrs for a good reason and human lives are one. Just don’t do it.

 

[prcguy]

It appears 126.1 is an aircraft approach frequency for Beijing International Airport. I would think if you fire up a cross band repeater on a major airport approach frequency you will have government authorities looking for you in a very short time. Good luck with your project.

 

[jamesbmwz]

I have tested a lot of amateur radios unblocked, single, dual, tri, quad, and have never found one to transmit in the VHF air band using a MARS type mod, even though some had AM mode. That is done by radio mfrs for a good reason and human lives are one. Just don’t do it.

I don’t know why all you think I am trying TX on air band. No! I am trying RX on air band and TX on UHF via cross band repeater mode. And RX on portable radio.

It appears 126.1 is an aircraft approach frequency for Beijing International Airport. I would think if you fire up a cross band repeater on a major airport approach frequency you will have government authorities looking for you in a very short time. Good luck with your project.

I don’t know why all you think I am trying TX on air band. No! I am trying RX on air band and TX on UHF via cross band repeater mode. And RX on portable radio.

The Air Band is AM, not FM. The radio can't transmit in AM. That's due to the design of the transmitter.

Since the radio cannot transmit in AM, it will not let you put the radio into cross-band repeat with one side of the radio configured for AM.

I don’t know why all you think I am trying TX on air band. No! I am trying RX on air band and TX on UHF via cross band repeater mode. And RX on portable radio.

I suspect the OP is trying to receive AM aircraft then retransmit to UHF to receive on a portable radio or similar, no tx on the airband. Some ham radios will do this, some maybe not. In the US if caught doing this it would be a violation of FCC part 97 rules. I wonder how the Chinese govt handles things like this?

I don’t know why all you think I am trying TX on air band. No! I am trying RX on air band and TX on UHF via cross band repeater mode. And RX on portable radio.

 

[MTS2000des]

I don’t know why all you think I am trying TX on air band. No! I am trying RX on air band and TX on UHF via cross band repeater mode. And RX on portable radio.


I don’t know why all you think I am trying TX on air band. No! I am trying RX on air band and TX on UHF via cross band repeater mode. And RX on portable radio.


I don’t know why all you think I am trying TX on air band. No! I am trying RX on air band and TX on UHF via cross band repeater mode. And RX on portable radio.


I don’t know why all you think I am trying TX on air band. No! I am trying RX on air band and TX on UHF via cross band repeater mode. And RX on portable radio.

Because a cross band repeater is just that, a BI-DIRECTIONAL repeater. Good luck with your air band piracy.

 

[jamesbmwz]

Because a cross band repeater is just that, a BI-DIRECTIONAL repeater. Good luck with your air band piracy.

I am sure It is single direction. RX from A and TX from B, cannot reverse.

 

[MTS2000des]

I am sure It is single direction. RX from A and TX from B, cannot reverse.

Captain Obvious...except you don't comprehend that CROSS BAND repeat function on AMATEUR radios is bi-directional. Regardless, you won't be able to retransmiit AM aircraft band this way, why you want to do it is irrelevant, the hardware is not capable.

 

[AK9R]

I am sure It is single direction. RX from A and TX from B, cannot reverse.

You may have the wrong radio for what you want to do.

Recent Kenwood mobile radios, such as the TM-V71 and TM-D710, have a feature called "Locked-band Repeater" which is like Cross-Band Repeater, but it only goes one way. I haven't tried to see if one of my Kenwoods would do a Locked-Band Repeat from air band to UHF. Maybe I can try that later today.

The Icom document I found which describes how to do Cross-Band Repeat with an IC-2730 doesn't mention only doing a one-way repeat. So, I assume that it can only do a two-way cross-band repeat. Since you are setting the radio with an air band frequency on one side of the radio, the radio is smart enough to not let you activate Cross-Band Repeat since it knows it can't transmit on air band. Yes, we understand that it's not your intention to transmit there. However, the radio is hard-coded to prevent you from doing so.

 

[JustinWHT]

I suspect the OP is trying to receive AM aircraft then retransmit to UHF to receive on a portable radio or similar, no tx on the airband.

I agree with prcguy's thinking. A single cross-band radio isn't going to work with AM aviation and FM radios.

A solution would be an AM aviation radio - an AM aviation scanner or HT radio - cross connected with an audio cable, 3.5 mm earphone/speaker plug to 2.5 mm microphone plug, to the transmitting radio.

There are two caveats - service specific prohibitions and license specific.

* Service specific prohibitions - MURS and FRS prohibit repeaters (to enlarge coverage area).
- MURS stations must not be operated as repeater stations or signal boosters. This prohibition includes store-and-forward packet operation.
- FRS was petitioned decades ago to prohibit store-and-forward repeaters.
- It does not appear repeating aviation radio over FRS prohibited. However it is prohibited to attach anything to an FRS radio that is not approved. This obviously includes signal boosters and antennas, but attaching an audio source is no different than a Bluetooth microphone and requires no approval.

Therefore... the OP's question does not ask to repeat MURS or FRS transmissions. So the above prohibitions would not apply.

* License specific prohibitions for Part 97 Amateur Radio licenses.
- Rebroadcasting of Personal Radio Service (GMRS and FRS) are prohibited.
- Rebroadcasting of commercial radio stations intended for use by the general public (AM and FM radio) are prohibited unless for immediate safety. Weather forecast allowed if originated by NOAA.
- Aviation radio is not intended for general public reception, so that would be allowed; but the rebroadcasting transmitter would require station periodic ID.

Therefore... Repeating aviation radio via Part 97 would be permitted.

Disclaimer - my two cents worth. YMMV

 

[alcahuete]

Therefore... Repeating aviation radio via Part 97 would be permitted.

You know he's in China right? Nobody cares about Part 97 in China.

 

[AK9R]

It's not a rules problem. It's a hardware problem. The radio can't transmit AM. Since cross-band repeat is, by most definitions, a two-way repeater, the radio assumes that what it hears on Band A will be transmitted on Band B and vice versa. If one of those bands is set to receive AM, the radio can't be set for cross-band repeat because it can't transmit AM. The radio's firmware knows this and won't let you set up a cross-band condition where the radio might be called on to transmit AM.

 

[mmckenna]

It's not a rules problem.

Yeah, especially not an FCC rules issue, since the OP shows his location as "Beijing, China"

 

[radiotweester]

I won't get in to the illegalities as it's been well covered by other replies. I've not been an Icom user for decades, but even back to the IC-2410 with TX opened, it only would RX and crossband in the range of 140-174 or 400-4710. I think it's always been a firmware thing.
Yaesu is different. With the FT-8900 I'm able to "crossband" repeat 927 to a VHF or UHF transmit.

 

[N4KVL]

The radio you are trying to do this with is not going to do what you want it to.

You need a gateway, JPS or the like and two donor radios plus associated interface cabling.