Ham Radio Forum

Jan van Vugt · Posted: Sun Oct 02, 2005 6:16 am Post subject: KENWOOD now has a D-STAR radio!

The Kenwood D-STAR that was displayed at the Japan Ham Fair – 2005 proves that other manufactures are willing to support the D-STAR standard. Who will be the next one to steep up to the plate?

You may see evidence of the Kenwood D-STAR at: http://www.pwsnet.jp/hamfair2005/images/0104.htm .
This is a text only picture, but there is enough English to prove the Kenwood connection. You can also see a picture of it at: http://www.pws-net.jp/hamfair2005/ or http://jh3ykv.rgr.jp/mt/archives/2005/08/21/index.html .

D-STAR is the digital standard for amateur radio. You will never find a commercially built ham radio with the APCO P-25 standard built in, because P-25 is a commercial standard. No ham radio will ever be type approved for commercial use. If you want to have interoperability with public safety radio, you will have to use commercial equipment. You will also have to have special authority, and pay for the extra commercial license that is needed, to be legal.

If the only thing that you want to do is listen in on an APCO P-25 conversation, get a scanner that is capable of doing that. That will be cheaper and easier than buying a commercial digital radio.

Inserted from http://www.icomamerica.com/support/forums/tm.asp?m=1098 .

There is now a D-STAR compatible UHF repeater in the Portland Oregon/ Vancouver Washington area.
The repeater is on 443.675(+5 MHz) and is located on Larch Mountain. The repeater is also capable of P25 operation. Please contact me via E-mail before you use the repeater.

Thanks and 73
Jim W7RY
w7ry at centurytel dot net

Please contact Jim - W7RY for more information.
_________________
Jan van Vugt - VE7TKO
"I am 100% sold on D-STAR"
I Monitor D-STAR DV on 145.600 MHz
Jan - The D-STAR Man

Guest · Posted: Tue Oct 18, 2005 5:26 pm Post subject:

What is really need is free software that combines 3 existing pieces of software into one package. (1) Speech recognition software will let you speak into a microphone and write a letter on your computer without typing on a keyboard. (2) PSK31 software and an add-on card in your computer will allow you to use your existing radio and antenna to communicate with a 30 Hz bandwidth by typing on your keyboard and receive text on your monitor. (3) Software exists for blind people to read books by scanning the text and hearing the words from a speaker connected to the computer. That text could come from your computer monitor.

Speech could be converted into symbols. The symbols could be communicated by radio with almost no bandwidth. The symbols could be converted into sound. But if the symbols are encrypted by hardware (APCO-25) or by software (D-Star), the people who have the encryption keys could make big bucks.

Could someone please write the software that is needed for us?

Mike n6ief mike-lebo@ieee.org www.lebos-lab.com

Jan van Vugt · Posted: Wed Mar 01, 2006 11:03 pm Post subject:

hamradiostuffing · Joined: 02 Oct 2005 Posts: 18

We do not need DSTAR what we need to let it die. DSTAR takes up more band width. Also the range from the reapeater is not as far as anolog.

Also note that MR Yellen and Mr Mclinton have stated that the repeaters will not work unless they are changed out. Just how many clubs are going to want to change their machines and where are they going to get the money. Surely ICOM is not going to give the DSTAR repeaters away. Be real!

"If you try to talk through an analog repeater, in digital mode, it will not work. The repeater must be able to receive a digital carrier and re-broadcast a digital carrier.

Since a digital carrier is different than an analog carrier, a non-digital radio can not re-broadcast the digital carrier. It's not just digital data, it's an actual digital signal. If you try to transmit, in digital mode, into an analog repeater, all the analog radios on the repeater will simply hear white noise and a digital radio listening will hear nothing. The digital radio will see activity on the signal strength meter, as would be normal when there is analog activity on the frequency.

_____________________________

Kevin McClinton, W7JRL
Amateur Technical Trainer

ICOM America, Inc.
2380 116th Ave. NE
Bellevue, WA 98004
Ph. (425) 454-7619
Fax (425) 637-8417
www.icomamerica.com

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hamradiostuffing · Joined: 02 Oct 2005 Posts: 18

The answer is, NO it will not work.

The reason is simple, the modulation scheme is not compatible, nor is the repeaters circuitry.

In a typical analog repeater, an FM demodulator is used to demodulate the FM signal, effectively "decoding" the voice signal imposed upon the carrier, by way of Frequency Modulation. The analog repeater then takes the analog audio, and passes it to the repeaters transmitter, where it is "re-encoded", by the FM modulator and sent over the air.

In a D-STAR repeater, an IQ demodulator is used, to "decode" the data imposed upon the carrier, by way of Gaussian Minimum Shift Keying. Once the digital signal, effectively ones and zeros, is extracted, it is buffered and regenerated. The regenerated signal is sent to the transmitter where it is "re-encoded" and sent out over the air.

As you can see, the operation is similar, up to the point where the signal is received, by the repeater, but after that, the process, and type of signal (one being audio and the other be data ones and zeros) is very different.

Any type of digital system, that uses tones, or audio, to represent data, can be passed through an analog repeater, because thatâ€™s what analog repeaters pass, Audio. Not all analog repeaters will pass that digital signal well, since there can be level and fidelity issues, but it should work. Thatâ€™s also why D-STAR a "true" digital system will not go through any analog repeater.

_____________________________

Matthew F. Yellen K7DN
Systems Engineer

yaesudude · Joined: 15 Feb 2007 Posts: 10

Really helpful ideas. Thanks guys!

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Yaesu FT-857 All Mode Transceiver - Get the Yaesu FT-857 Ultra Compact HF/VHF/UHF 100 W All Mode Transceiver Catalog

Radio_Girl · Joined: 26 Feb 2007 Posts: 10

Kenwood has always made great HAM radio hardware, so I'm confident this is a good piece.

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Kenwood TS-480HX / TS-480SAT - TS-480HX/TS-480SAT HF/50MHz All-Mode Transceiver by Kenwood Communications Division