Irish Rover
Well-known member
I posted in another thread re Matsutec that I'd ordered an Onwa KS200A direct from Aves Marine. Because I didn't have a spare NMEA0183 port on my chartplotter I also ordered an Onwa KC-2W bi-directional NMEA 0183/2000 converter with WiFi.
My son brought them out to me and we installed them last week. The AIS was working fine both receiving and sending and we were able to connect the Navionics app on a tablet to the KC-2W to overlay AIS. Everything seemed to be OK but I was getting an error on my Garmin GPS Map 820xs saying "lost heading sensor connection". We thought this might be due to interference from the GPS antenna we placed reasonably close to the plotter so we moved it multiple times to different locations but the problem persisted. Eventually, after trying many options, connecting and disconnecting various bits from the network we removed the KC-2W converter and connected the KS200A directly to a NMEA0183 port on the chartplotter**. Finally, this worked and there were no more errors on the plotter.
** To be able to connect directly to the plotter we had to take my Standard Horizon 2200 out of the network to free up an 0183 port. I had it connected initially to display AIS targets on the plotter which is obviously no longer necessary with my transponder connected. On the negative side I can no longer get the AIS overlay on Navionics as my Garmin plotter is not compatible with the Navionics app - you'd have to wonder why - since they're effectively the same company.
I have no idea why the KC-2W was causing the heading sensor problem in my plotter. From what I've read online many other owners are using them very happily without issues. I've been in touch with Alan from Aves Marine throughout this process and he has been excellent. I'm returning the converter for a full refund. I know the Matsutec unit is cheaper and many on here are using them satisfactorily but I'm very glad I decided to buy Onwa for the excellent service from Alan and Aves.
I hope this long report is of use to others.
My son brought them out to me and we installed them last week. The AIS was working fine both receiving and sending and we were able to connect the Navionics app on a tablet to the KC-2W to overlay AIS. Everything seemed to be OK but I was getting an error on my Garmin GPS Map 820xs saying "lost heading sensor connection". We thought this might be due to interference from the GPS antenna we placed reasonably close to the plotter so we moved it multiple times to different locations but the problem persisted. Eventually, after trying many options, connecting and disconnecting various bits from the network we removed the KC-2W converter and connected the KS200A directly to a NMEA0183 port on the chartplotter**. Finally, this worked and there were no more errors on the plotter.
** To be able to connect directly to the plotter we had to take my Standard Horizon 2200 out of the network to free up an 0183 port. I had it connected initially to display AIS targets on the plotter which is obviously no longer necessary with my transponder connected. On the negative side I can no longer get the AIS overlay on Navionics as my Garmin plotter is not compatible with the Navionics app - you'd have to wonder why - since they're effectively the same company.
I have no idea why the KC-2W was causing the heading sensor problem in my plotter. From what I've read online many other owners are using them very happily without issues. I've been in touch with Alan from Aves Marine throughout this process and he has been excellent. I'm returning the converter for a full refund. I know the Matsutec unit is cheaper and many on here are using them satisfactorily but I'm very glad I decided to buy Onwa for the excellent service from Alan and Aves.
I hope this long report is of use to others.
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