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So a buddy loaned me his Icom 2200h with UT-118 installed.

It's been a serious learning experience getting this thing programmed. On a scale of 1-10 the manual is about a 2 in terms of actually getting the radio on the air. What's amazing me is how little info there is on the web about how to set up your Icom rig to d-star. I finally found a decent PDF file that explains this somewhat.

I've been trying to hit the Fed Way ARC's d-star repeater on 146.84 and finally got to hit the repeater. (I knew this worked thanks to their d-star status. It logged my callsign and message.)

Getting digital voice however has been nothing short of a joke. You really do need close to 100% signal quality. I'm getting S4-S5 on the meter and it seems that only about 1 in 10 signals are getting thru.

I suppose it could be a problem and/or limitation with this particular d-star implementation (with this radio.) So far, though, I'm not terribly impressed.

I'm trying to listen to the d-star user's group on this repater (Sunday's 7pm) and I'm only able to decode 10% of the time. :?

On top of Lincoln Tower in downtown Bellevue. At some point, these will have a gateway - but, their computers are off line at the moment:

443.000 K7LWH B
145.130 K7LWH C

The ones at ICOM may or may not be on the air:

145.290 N7IH C
443.575 N7IH B

There's also the Gold Mtn repeater, seems to have decent coverage in your area:

444.5625 WD7STR B

And, for now there's one on Mt. Pilchuck (may not be so good in Bellevue):

440.325 NR7SS B


Yea, D-Star is a bit less forgiving - seems that I have to have a good path, and a lot of signal into the repeater to make it work. "R2D2" effect happens pretty readily if there's any multipath at all.

But, when it works, it sounds pretty good. It's just different.

Brad.

_________________
Whatever.....

For grins you could try the Fed Way sites.
These have pretty good coverage to the north.
They are gateway connected.

146.840
443.850

Probably a dumb question but what is the B or C after the call signs for the above Dstar repeaters?

I don't know anything about Dstar except it is Icom digital :D

Thanks Jim

_________________
" SILENCE IS CONSENT "

Made to Government Specs:
1) Measured with a micrometer.
2) Marked with a chalk.
3) Cut with an axe.

Jim N7UAP - Bellingham, WA / InterceptRadio.com

D-Star site controllers have 4 ports.
They are labelled "A", "B", "C", and "D".

The purpose is for routing and control, primarily routing.

If you are attempting to contact a specific HAM on a specific port of a remote, gateway connected system, you may include the letter in the 8th position of the target system you are calling, and your call will route out of that port of the site controller.

There are other reasons as well, but this is the most significant.



Currently ICOM is the only radio manufacturer in the D-Star market, however the "DV Dongle" has aready been out for over a year, and has the vocoder included in a USB device that allows you to access the D-Star gateway connected network from your computer.

There also is an open project of some kind going on right now, I am not too familiar with it, but the plan is to offer a non-ICOM repeater solution and perhaps also a SDR (software defined radio)type solution.

D-Star was designed under contract by ICOM's engineering company, however the IP is not owned by ICOM, it is JARL intellectual property and (theoretically) anyone can build a D-Star product.

Thank you.

_________________
" SILENCE IS CONSENT "

Made to Government Specs:
1) Measured with a micrometer.
2) Marked with a chalk.
3) Cut with an axe.

Jim N7UAP - Bellingham, WA / InterceptRadio.com

If you are interested in learning more about D-Star, the Federal Way club is a good resource.

They do a regular D-Star meeting usually once a month.
This is separate from the monthly club meeting and is open to all.

Thanks. I am from Bellingham so I think I'll look online for info :D

_________________
" SILENCE IS CONSENT "

Made to Government Specs:
1) Measured with a micrometer.
2) Marked with a chalk.
3) Cut with an axe.

Jim N7UAP - Bellingham, WA / InterceptRadio.com

I was trying the 146.84 repeater as per my original post. The 2200 is only a 2m radio, so can't do 70cm.

Hmmm time for some remedial reading...

While D-STAR can and often does transport voice, over the air the modulation is digital (GMSK, QPSK, or 4FSK at a maximum of 4.8 kbs according to the spec). The D-STAR protocol itself is fully documented and open, but when you get to where the AMBE-encoded digital voice sample fits, it shows where the bytes go but nothing about the AMBE encoding itself. The digital AMBE protocol is proprietary and as far as I understand, you can't decode it off the air unless you have the proprietary chip from the company who delevoped AMBE called Digital Voice Systems, Inc. or DVSI. This chip can be in an Icom rig, the DV-Dongle, or a homebrew rig using the proprietary chip.


I believe the AMBE technology is patented so it would be illegal to create a compatible vocoder even if one doesn't own an AMBE chip. From a technical standpoint I think it would be nearly impossible to reverse-engineer the protocol strictly by looking at just an off-the-air AMBE data stream extracted from D-STAR packets