I'm using the same adapter to connect my HX851 portable with GPS to an ACER netbook running SeaClearII. I had trouble getting it to connect with the netbook (Win7 starter) so I tried an ACER laptop running Vista. This seemed to connect ok once Windows found and loaded the drivers. The blue light on the adapter came on solid instead of blinking. But Seaclear didn't update the position so I don't think it's hearing the GPS. Do you have any tips? I think I have the com port in Seaclear set to the same as the bluetooth adapter. The HX851 doesn't seem to have any settings. At least I couldn't find anything in the manual.
There are about a dozen things that could be wrong. Hard to list them all.
First, NMEA standard is 4800 baud, 8 bits, no parity. Every link in your chain needs to be at the same setting. If your radio has no adjustable settings, chances are it is sending 4800/8/n. Your bluetooth adapter probably defaults to 9600, so you need to set it to 4800. Your Bluetooth receiver in your PC also needs to be 4800, and will send the transmission to a virtual COM port. That COM port is what your chartplotter software will see, and both need to be the same COM port and the same baud rate.
Your Bluetooth software may have a configuration utility that allows you to specify the COM port and baud rate. If not, go to Device Manager and select Ports, then the Port Settings tab to make adjustments. Native Windows Bluetooth support is notoriously bad, so you may need to go to third party software. Figure out whose Bluetooth transmitter is in your machine, and go look for their driver software online. I have a Toshiba chip in my netbook, and had to try 3 different versions of the Toshiba driver before I found the one that was 100% reliable.
Debugging all this took me a few hours. But once it's running, you never have to do it again.
Frankly, though, I would recommend that you just go buy a GPS puck to plug into your PC. In order for the HX851 to send/receive NMEA, it needs to be in its charging cradle, which is not weather resistant. And part of the whole purpose of having a handheld is to keep it out in the cockpit with you. So you'd be better off getting an inexpensive dedicated GPS puck for your PC. I got a Delorme LT-20 for $18, so they can be found cheap.