RayStar 125 GPS update speed

[Asureyez]

I deleted the old POS GPS dumb antenna that led to my RN300 GPS plotter. When it worked (about 30% of the time lately) it would provide very rapid updates and my reported position was always within a nanometer of reality. I was getting heading data from the RN300 to the RL80CRC via Sea Talk network over a dumb terminal block connection.

This new 125 is set up on Sea Talk but reports very slowly. The RN300 is in "repeater" mode, and is also on the Sea Talk network equally with the RL80CRC. I notice perhaps a 20 second lag at times in reported position vs reality. I've searched for any set up routines through the RL80CRC set up screens (which are different for the 125) to perhaps force more rapid updates, but NADA.

My Raytheon Type 1 course Computer receives its NAV data on NEMA via the RL80. I suppose I could add the course computer to the Sea Talk net work for heading data as ther ear eunused ST inputs. The course keeping for the Autopiolt is a little snaky (100 ft swings over 1000 ft was observed this past weekend when before it was rock solid) for the first time even with rudder reponse at #2 setting. I'm thinking this slow heading data from the 125 might be the issue there.

1. Anyone got the 411 on such the settings for the 125? :huh:

2. Sending heading data via SEA TAlk to a vintage Rayethon Type 1 computer? :huh:

 

[Four Suns]

I pretty much have the same setup as you and don't have a 20 second lag... I spliced mine into the SeaTalk network... and it gives pretty much real time updates. When I played around with the multiplexer a few years ago (it bridges the Raymarine stuff to the Windoze PC), it was giving an update several times a second on the network..... If there is a way to adjust settings for the 125, I'm not aware of it.. (but there may well be).

I thought you raved about how great the RN300 was some time ago... it's a POS.

 

[fc3]

I would take the RN300 out of repeater mode. If you have the RL80CRC, the GPS125, and the RN300 all on the same Sea Talk bus, repeater mode might be causing a lot of excess chatter on the bus. Since Sea Talk is a slow-speed CDMA type of architecture, that might account for the update delays. Since they are all on the same bus, there's nothing to repeat as all instruments share the data without the need for it to be repeated. On the other hand, if the 125 is connected only to the RN300 and the RN300 shares another Sea Talk bus with the RL80CRC and anything else installed, such as an autopilot, then you would need repeater mode.

Best regards,
Frank C

 

[Asureyez]

It was my understanding that the Repeater mode was a passive setting and that it caused the RN300 to simply display data it was fed and passing nothing back out. It now simply listens displays and acts otherwise dumb.

The settings are "GPS" and "Repeater" where the GPS mode was how it was set when it WAS THE GPS, now in repeater mode it isn't the GPS any longer it just a display as the 125 is the entire GPS system all stuffed on a chip on the arch.

Do it have it wrong?

 

[osd9]

The RN300 can either be Master or slave (repeater).....there are no other modes other than off.

You may want to play with the "Bridge NMEA Heading" setting....

Bridge NMEA Heading​

The HSB Series displays bridge NMEA input data to the SeaTalk bus (see​

Section 8.8​

​

​

​

​

).
The Bridge NMEA Heading option can be used to prevent NMEA heading
data being bridged onto the SeaTalk bus.
For example, if you have a course computer connected on SeaTalk and
NMEA, and an active compass connected on NMEA (for MARPA), SeaTalk
data overrides NMEA data in the course computer. You should therefore
switch OFF the Bridge NMEA Heading option to ensure the course computer​

receives the same NMEA heading input as the radar system.

 

[osd9]

You can also play with this setting....

GPS SOG/COG Filter​

Select the SOG/COG filter setting as required. This can be set to​

​

HIGH,​

MEDIUM​

​

or LOW. The factory default is MEDIUM.
The velocity vectors calculated from the GPS Signal give an
instantaneous measure of speed and direction of the GPS antenna. The
COG and SOG can therefore seem erratic under certain conditions. For
example, when a vessel is moving slowly through rough seas, the antenna
moves from side to side as well as in the direction of the vessel.
The SOG/COG filter averages the velocity vectors to compensate for the
oscillating motion of the vessel, giving a clearer indication of the vessel’s
course and speed.
Slow moving vessels, or vessels sailing in rough seas will benefit from a
high setting, whereas a power boat that can quickly change speed and
direction will benefit from a low setting.​

The filter does not affect the calculation of the GPS position.

 

[Asureyez]

Thanks Dom;

I picked up during install the "Bridge NMEA Heading" issue and it is set to Off, as well the Filter was set to Medium as it was the old setting. I did not try it on low as most of the boat's use is a slow ICW speeds. Medium seemd the most likely setting. :huh:

Looks like it's time for a updated course computer or a Gyro add on?

 

[fc3]

Dom has it right. Thanks for the correction.