TH-D74 not heard on XLX reflectors

Help with D-Star related issues
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w7efs
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Re: TH-D74 not heard on XLX reflectors

Post by w7efs » Mon Sep 16, 2019 3:41 pm

Good find, David N6XVZ. On an ID-51, the “Own Callsign 1 / Own Callsign 2” fields can't be entered from the HT with lower-case (lc) characters; even the CS-51 programming software coerces those two fields to upper-case; lower||proper case is possible in the TX Message though.

You might consider informing Kenwood Support of the issue, as they may want to implement a software/firmware change to prevent such problems for the unsuspecting.
Last edited by w7efs on Sat Oct 05, 2019 4:23 pm, edited 1 time in total.

AE5PL
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Re: TH-D74 not heard on XLX reflectors

Post by AE5PL » Wed Sep 18, 2019 11:16 am

The callsign fields (there are 4) are assumed upper case. While not delineated in the spec as upper case only, it has always been assumed that callsigns are upper case as has been represented since the beginning of licensed amateur radio. The callsign also always starts in the 1st character position (_AE5PL__ does not equal AE5PL___). I mention this because this was another cause found that the CQCQCQ__ was actually entered via software as _CQCQCQ_.

So what are those 4 characters that Dave had an issue with? They are actually part of the station call denoted as "Own Callsign Extension". This was placed in the D-STAR protocol dating back to the original spec to provide for international reciprocal operations where the country being visited requires the inclusion of their prefix in the transmitting callsign identification! While the meaning has been usurped by most (including by me) in using the 4 character extension to indicate things like name, radio, etc., it is good to remember why it is there and what its real purpose is. The extension is not used for anything other than extended identification in the protocol.

Apparently the XRF/XRX software is enforcing upper case for callsigns and not trimming leading spaces which is perfectly within the author's perview and, for the latter, actually how callsigns should be handled. If you vary from the above definitions, your results may be unexpected as was the case with this issue.

k2dls
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Re: TH-D74 not heard on XLX reflectors

Post by k2dls » Thu Sep 19, 2019 1:26 pm

Peter, very interesting about the original intended use of the "Own Callsign Extension" field.

I was recently thinking that there must be a way to address any prefix rules under CEPT or other reciprocal agreements.

73

N6XVZ
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Re: TH-D74 not heard on XLX reflectors

Post by N6XVZ » Sat Sep 21, 2019 3:34 am

Good insights; thank you all. I like the idea of suggesting Kenwood force upper case; I'll follow through on that.

It's interesting now that I know this how many people I see with lower case. I'm making it a point to tell people, esp if they id with D74.
Help spread the word!

ZUMspot, Rpi 3 B+, Th-D74

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w7efs
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Re: TH-D74 not heard on XLX reflectors

Post by w7efs » Sun Sep 22, 2019 7:23 pm

N6XVZ wrote:
Sat Sep 21, 2019 3:34 am
...
Help spread the word!
Two vendors at nearby tables each had a TH-D74 Saturday, and both were glad when I informed them of your discovery; I'm sure they'll tell others too.

ct1dvm
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Re: TH-D74 not heard on XLX reflectors

Post by ct1dvm » Thu Sep 26, 2019 6:03 am

AF6VN wrote:
Sun Sep 15, 2019 4:23 pm
http://www.arrl.org/files/file/D-STAR.pdf only specifies ASCII for the fields, and http://www.aprs-is.net/downloads/DStar/ ... overed.pdf is even less informative...

If there is anything specific I can't locate it.
http://www.dstar.org.au/wp-content/uplo ... -V2.01.pdf

Also, in radio manuals.

AF6VN
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Re: TH-D74 not heard on XLX reflectors

Post by AF6VN » Thu Sep 26, 2019 5:41 pm

I see nothing in there regarding a case restriction on the radio(s), and no mention at all of the extension field.

The only place I found specifying upper case was in registering a D-Star account, and with regards to the 8th character position of the call sign field.

If I missed something, please identify the page in that document that applies.

And obviously, no one has found any specification of upper case only in the Kenwood manual.

--
AF6VN
Dennis L Bieber

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KE0FHS
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Re: TH-D74 not heard on XLX reflectors

Post by KE0FHS » Thu Sep 26, 2019 7:15 pm

Dennis, I looked through that doc and found the same thing as you did, no mention of case restriction. I also looked through the D-STAR Technical Specification doc (https://www.jarl.com/D-STAR/shogen.pdf). It makes no specific mention of case restriction that I could find. However, all of the examples of callsigns that are given show UPPER CASE used, for example: "Ex. W$1AAA_G." It does specify ASCII letters and numbers, but ASCII letters are both upper- and lower-case.

In my opinion, when variations of a variable like a callsign--one using uppercase, one using lowercase, and one using mixed case--do not actually mean different values (as opposed to something like a password, where an uppercase and lowercase letter are actually interpreted differently), then smart programming would simply account for that. It may be true that the XRF/XRX software is enforcing upper case for callsigns, but it may also be that the developers simply didn't make allowances for callsigns being entered using different variations of case.
73, Toshen, KE0FHS
Playing with Pi-Star (unofficial notes about setting up and using Pi-Star):
https://amateurradionotes.com/pi-star.htm

AE5PL
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Re: TH-D74 not heard on XLX reflectors

Post by AE5PL » Mon Sep 30, 2019 3:50 am

I refer you to the ITU documentation on Fixed Mobile radio identification and specifically, the callsign formation possibilities document. As I stated before, the D-STAR specification authors specified that the protocol was written for international amateur radio use and callsigns would adhere to international standards. Those standards always call out upper case combinations; never call out upper/lower; because upper/lower case characters are, in fact, unique. I realize that people whose primary learning has been in the Windows world (hey Linux folks, what happens if you enter Ls on a command line instead of ls?) and texting feel that they should be able to use either case. Look at your license: your callsign is upper case. As I stated, the field in question was placed there for international reciprocal operation where a country prefix is to be entered. That Kenwood made an error in allowing lower case for a fieild that is supposed to be a callsign prefix does not make it right. It makes it an error on Kenwood's part. As I also said, if you try to put lower case in a callsign field (in any amateur radio protocol) and it doesn't work with some software, don't blame the software author for making their software ITU compliant. Try using upper case for your callsign to be sure it works with all software and hardware.

N6XVZ
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Re: TH-D74 not heard on XLX reflectors

Post by N6XVZ » Fri Oct 04, 2019 2:25 am

Well this is going sideways.....

I adhere to the software principal of "protect the user from making unintended mistakes". By allowing me to enter lower case and it works in some cases but not others - that's a problem I think we all agree upon. I don't study international standards for ham radio to the level of detail presumed. I prefer upper/lower case for readability.

However I stated and still agree that it looks like a bug to me in the radio to allow it if it's truly a standard and not allowed elsewhere.

The fact is it's ambiguous - not clearly stated anywhere easily found/referenced. Until now hopefully.

It's not worth this much blow on it. I just wanted folks to know that they could get bit by it if they didn't know and it was a particularly insidious bug in something that had nothing to do with pistar but a gap somewhere along the ecosystem.

Let's move on!

ZUMspot, Rpi 3 B+, Th-D74

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