Using YADD and Yadd2map


@PaulTurkk
 

Hello all,

I have been lurking for a week or so and have been monitoring DSC for a month now. Tried YADD, Multipsk, BC-GMDSS, and DSC decoder. Mostly I've settled on Yadd for now.
Today I tried Yadd2map for the first time, nice program. After reading through prev posts it seems to be up and working.
A few logs made it to yaddnet. Do I need to register or apply to yaDDNet?
Before Y2Map I had the setting below to both, does this effect what shows on YaDDNet at all or is it only for the log tab on Yadd or....?

I use CW -250 filter on the RSPdx on the exact frequency, I do get between 30-60% errors and have been wondering if it is my settings or conditions.
I have many questions; it is getting late here.
Thanks


John Pumford-Green
 

On Mon, 10 Oct 2022, pturkk@... wrote:

Hello!

A few logs made it to yaddnet. Do I need to register or apply to yaDDNet?
There's no registration needed for YaDDNet, just configure "Remote Logging" on YaDD with the correct Host/Port/Receiver ID and tick the box to enable uploads.

In case anyone else reading is unsure of the details:

Host : www.yaddnet.org
Port : 50666


Before Y2Map I had the setting below to both, does this effect what shows on YaDDNet at all or is it only for the log tab on Yadd or....?
The ECC "OK, ERR, Both" setting is for YaDD's own use.

YeDDNet only handles messages that have "ECC OK" and discards any that have "ECC ERR". I used to store messages with "ECC ERR" and then run a script to delete them after a certain time but decided to only handle error free messages, to avoid confusion. DSC Messages with errors can appear to be from stations totally unrelated to the actual source, and can't be trusted, even when there doesn't seem to ba anything grossly wrong, most parts of the message look "correct"....

Several years ago I decided to just discard any incoming "ECC ERR" messages "at source" as they come into YaDDNEt.

If you look at the logging page:

http://www.yaddnet.org/pages/php/logger_messages.php?

you'll see which incoming messages are kept and which are discarded.

DSC has 2 different error checking mechanisms - the Parity check on each message "symbol" individually and the overal message "ECC" checksum.

Symbol Parity fails show as decoded symbols with "~".

Overall checksum ECC fails show as "ECC ERR". It is possible to have a correct ECC even of there are Parity fails.

For an overview of the protocol, and some hints on how to interpret messages with errors, look at my (never really completed) DSC Guide:

http://www.yaddnet.org/pages/MF_and_HF_DSCguide.pdf

I have no experience with YaDD2map and can't help with any questions relating to how it functions with YaDD.

Similarly I don't have any in depth knowledge of YaDD itself, Dirk Claessens wrote YaDD (as well as YaND for NAVTEX).


I use CW -250 filter on the RSPdx on the exact frequency, I do get between 30-60% errors and have been wondering if it is my settings or conditions. I have many questions; it is getting late here. Thanks
DSC requires rather wider bandwidth than 250Hz. The FSK shift is 170Hz, keyed at 100 baud, so the spectrum will be wider than your filter. I guess an SDR's DSP filters will be very sharp too, unlike an old analogue RX, which are a little more forgiving, with their more gently sloping response.

Unless there is strong interference within the selected bandwidth causing AGC to reduce the gain, and push weak DSC signals into the noise (unlikely with a good SDR) it's usually better to leave the RX IF bandwith wide.

YaDD has its own DSP filtering to select the wanted audio signal centered on your chosen audio centre frequency. Narrow RX IF filters generally don't help that much, and if they are too narrow they can cause problems. I wonder if your high decode error rate is due to the 250Hz filter? Try widening it to at least 500Hz, or more.

Thanks for feeding data to YaDDNet.

John
GM4SLV

--
http://www.yaddnet.org/
https://www.gm4slv.org.uk/


@PaulTurkk
 

John,

Very grateful for the detailed explanations on YaDDNet message handling and DSC errors. (I have seen the MF- HF guide before, but need to give it a good looking over.)

It is nice to be able to peek at what I'm receiving at home from work! I have been changing freq mornings and night and it is satisfyingly to be able to add data to the net. 

Will try the 500Hz or wider filters. Without much experience yet I need to try everything. 


--
73

Paul T
St. Joseph, Michigan, US
KC2LPG (Exp)
Rx- RSPdx
Ant- Sirio discone / MLA-30 Loop