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Any Dual-Banders That Program 12.5kHz Deviation?

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com501

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I am looking for a new dual bander (2m-440) to replace my venerable Kenwood in my new Expedition.

It needs to have wide coverage on receive, and be capable of programming 12.5kHz deviation, as well as being able to handle the new 6.25 channel offsets.

Yes, we have a narrowband repeater on the ham bands.

It would be nice if there is a mod out there for out of band transmit too, since it goes to Baja every year.

Anyone?



Buehler?
 

W9BU

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Current land mobile and amateur radios are typically set up for +/- 5 kHz deviation. Using Carson's formula, this results in a bandwidth of 16 kHz ( BW = 2 (max deviation + max modulating frequency) = 2 (5 kHz + 3 kHz) = 16 kHz). Traditionally, these channels have been on a 15, 20, or 25 kHz separation on VHF and 12.5 or 25 kHz separation on UHF.

The new narrowband radios are set up for +/- 2.5 kHz deviation. This results in 11 kHz bandwidth using the above formula. These channels will be on 7.5 or 12.5 kHz separation on VHF and 12.5 kHz separation on UHF.

Current model Kenwood amateur mobiles will do +/- 5 and +/- 2.5 kHz deviation and they have channel steps of 5, 10, 12.5, 15, 20, 25 kHz. At the Dayton Hamvention this year, I asked Don Wingo from Kenwood about the lack of a 7.5 or 2.5 kHz step size because that will make it challenging to tune the radio to the proper narrowband frequencies. He was not aware of the problem until I brought it up.

I believe the Wouxon handhelds with the latest firmware have 7.5 kHz steps.
 

com501

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The Wouxon handhelds do, but I want something with 50 watts. NOWHERE in the Kenwood specs does it tell you it will program for narrowband. Will all the dual banders do it, or do I need to make a 250 mile trip to the nearest ham radio store to play with one?

Anyone know?
 

W9BU

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NOWHERE in the Kenwood specs does it tell you it will program for narrowband. Will all the dual banders do it, or do I need to make a 250 mile trip to the nearest ham radio store to play with one?
You could read the manual.

Page 69 of the Kenwood TM-V71A manual.
1. Enter Menu mode and access Menu 102 (MODULAT)
2. Set the mode to AM, FM, NFM.
Since this particular radio only has an FCC Equipment Authorization for Part 15 and additional equipment authorization is not required for a VHF/UHF radio operating under Part 97, I don't think Kenwood is required to be any more specific about the modulation types.
 

NDRADIONUT

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The thing you have to watch out for is the radios that they cut down the dev. But the recieve stays wide...the FT 8800 and for that matter the FT90 hand held both actually have narrow recieve....
 

com501

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The thing you have to watch out for is the radios that they cut down the dev. But the recieve stays wide...the FT 8800 and for that matter the FT90 hand held both actually have narrow recieve....
THIS is the kind of answer I am looking for, since I NEVER buy ham equipment as a general rule, I knew someone would know. The 'RTFM' answers and explanations about type acceptance and bandwidths I DON'T need. I am IN the two way radio industry and HAVE been for 40 years. I went through 'narrowbanding' when it was 15kc deviation.....

THANK YOU, NDRADIONUT and others for concise, on topic replies, without the unnecessary 'fluff' about type acceptance, etc. :)
 
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The Baofeng UV-3 hand held radio does both wide and narrow and the receiver does indeed select the correct bamdwidth on receive and transmit, plua covers both bands. Not bad for a $40.00 radio. Check Yahoo Groups, very active group, with lots of information.
 

com501

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Thanks, that's great, but I need a MOBILE. 50 watts, minimum. I usually run a 1/4 kilowatt.
 

MTS2000des

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Current land mobile and amateur radios are typically set up for +/- 5 kHz deviation. Using Carson's formula, this results in a bandwidth of 16 kHz ( BW = 2 (max deviation + max modulating frequency) = 2 (5 kHz + 3 kHz) = 16 kHz). Traditionally, these channels have been on a 15, 20, or 25 kHz separation on VHF and 12.5 or 25 kHz separation on UHF.

The new narrowband radios are set up for +/- 2.5 kHz deviation. This results in 11 kHz bandwidth using the above formula. These channels will be on 7.5 or 12.5 kHz separation on VHF and 12.5 kHz separation on UHF.

Current model Kenwood amateur mobiles will do +/- 5 and +/- 2.5 kHz deviation and they have channel steps of 5, 10, 12.5, 15, 20, 25 kHz. At the Dayton Hamvention this year, I asked Don Wingo from Kenwood about the lack of a 7.5 or 2.5 kHz step size because that will make it challenging to tune the radio to the proper narrowband frequencies. He was not aware of the problem until I brought it up.

I believe the Wouxon handhelds with the latest firmware have 7.5 kHz steps.
My Yaesu FT-8800 does narrow RX and TX, synthesizer 6.25 steps and 12.5 but not 2.5 steps. It does narrow the RX bandwidth and TX deviation when set to NARROW.
 
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