DPRS data

Help with D-Star related issues
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KE0FHS
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Re: DPRS data

Post by KE0FHS »

You might want to have a look at what Pete Loveall, AE5PL, says in his D-PRS article, as well as what is written in some of the references he mentions:
http://www.aprs-is.net/DPRS.aspx
73, Toshen, KE0FHS
Playing with Pi-Star (unofficial notes about setting up and using Pi-Star):
https://amateurradionotes.com/pi-star.htm
OE1AKA
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Re: DPRS data

Post by OE1AKA »

KE0FHS wrote: Sat Apr 06, 2019 3:08 pm You might want to have a look at what Pete Loveall, AE5PL, says in his D-PRS article, as well as what is written in some of the references he mentions:
http://www.aprs-is.net/DPRS.aspx
Thanks, I have read that.

But it's not mentioning the TH-D74. So my main question remains: Why is the TH-D74 not fully compatible with D-PRS? How is Pete's (AE5PL) effort to work with Kenwood on a fix going?

Also it doesn't say anything about D-RATS. So my second question remains as well: what format is the https://www.icom.co.jp/world/products/a ... s/rs-ms1A/ app using for chat and photo transfer? Is it D-RATS compatible?

Thanks! And sorry if those are obvious questions. 73
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KE0FHS
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Re: DPRS data

Post by KE0FHS »

73, Toshen, KE0FHS
Playing with Pi-Star (unofficial notes about setting up and using Pi-Star):
https://amateurradionotes.com/pi-star.htm
OE1AKA
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Joined: Tue Apr 02, 2019 10:13 pm

Re: DPRS data

Post by OE1AKA »

KE0FHS wrote: Sat Apr 06, 2019 6:23 pm You can read more here: https://groups.yahoo.com/neo/groups/Ken ... opics/1766
Thanks, Dean Gibson's (AE7Q) messages in that thread explained it perfectly.

There are two modes:
D-PRS mode (DV-A in the Icom ID-51+ manual) which is a custom format involving ONE string with a 16-bit checksum.
NMEA mode (DV-G in the Icom ID-51+ manual) which transmits traditional NMEA data. This is not D-PRS.
The Kenwood D74 can receive and display DV-A/D-PRS, but does not transmit DV-A/D-PRS.
The Kenwood D74 sends DV-G, but is missing any means to input the PRS symbol (http://www.aprs-is.net/DPRSCalc.aspx), it transmits spaces instead.

A firmware update implementing either the DV-A/D-PRS or fixing DV-G was not released by Kenwood in the last two years since this message was originally posted in the above Yahoo user group. Apparently Kenwood has no intention to fix this.
AE5PL
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Re: DPRS data

Post by AE5PL »

D-PRS mode (DV-A in the Icom ID-51+ manual) which is a custom format involving ONE string with a 16-bit checksum.
NMEA mode (DV-G in the Icom ID-51+ manual) which transmits traditional NMEA data. This is not D-PRS.
The second statement is FALSE. NMEA/GPS mode is the ORIGINAL mode that D-PRS was created from. Originally, GPS-A (now called D-PRS) mode did not exist (was introduced with the Icom 2820). We created the D-PRS translation specification using the front panel message that is used in the GPS mode (now called NMEA). This was necessary due to the high bit error rate that occurs in the unprotected serial part of the DV stream. That specification is still in place today and the latest D-STAR specification includes the variable message capability in the section describing GPS mode (neither GPS or GPS-A mode were in the original D-STAR specification).

The "accommodation" done for the TH-D74 is actually blatantly against the published D-PRS specification as it -assumes- that all radios with no message (20 spaces) want to be seen (false), are TH-D74s (false), and are free from bit errors (false).

We are still pushing Kenwood to update the firmware but believe we will see a bigger release this year that will, at a minimum, allow modification of the GPS 20 character message per the D-STAR specification.
K2IE
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Re: DPRS data

Post by K2IE »

AE5PL wrote: Fri Aug 24, 2018 7:53 pm
So "no", DStarMonitor fully complies to the D-STAR and DPRS specifications which does not allow for potential mangled packet and non-standard packet generation. "Yes", we (myself and others) are in talks with Kenwood to make their radio compatible with all D-STAR gateway DPRS implementations so a user can know their position is being gated properly regardless of the gateway they are using.

73,

Pete AE5PL
Great to see you on the case Pete, since you truly "get" APRS.

73
OE1AKA
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Re: DPRS data

Post by OE1AKA »

AE5PL wrote: Thu Apr 11, 2019 11:36 am We are still pushing Kenwood to update the firmware but believe we will see a bigger release this year [..]
Thanks for your effort!
As for a major firmware update from Kenwood this year, I believe it when I see it.
OE1AKA
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Re: DPRS data

Post by OE1AKA »

@AE5PL
Updated item : (Version 1.08 1.09) [June 26, 2019]

The following features are updated.

1. Enables decoding of standard APRS telemetry format.(Displays telemetry packets sent from the PSAT2.[..]
Source: https://www.kenwood.com/i/products/info ... ate_e.html

Is this it? Or just receive improvement?
AE5PL
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Re: DPRS data

Post by AE5PL »

OE1AKA wrote: Sun Jun 30, 2019 6:39 am @AE5PL
Updated item : (Version 1.08 1.09) [June 26, 2019]

The following features are updated.

1. Enables decoding of standard APRS telemetry format.(Displays telemetry packets sent from the PSAT2.[..]
Source: https://www.kenwood.com/i/products/info ... ate_e.html

Is this it? Or just receive improvement?
Nope. Unfortunately, the only D-STAR related function that got add/changed in the D74 is the support for XLX reflectors. I am very disappointed that Kenwood did not take the extra step of making the D74 fully D-STAR compliant and make the GPS message modifiable. :( :(
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