GPS 152H help needed!

What I want to know is, how do I power my GPS 152H at home...

Looking at the PDF installation manual (P4) all you need to do is supply the unit with 10-40 volts at 5 Watts (max) via pin 1 and 2 of the interface connector. A car battery or anything that takes the place of one (e.g. cigarette lighter AC adapter) should do that job.

...but presumably I need some driver software for the laptop to recognise the serial/USB device?

Two things. You'll need a USB/serial adapter if your laptop doesn't have a serial port (and it most likely doesn't). That would come with a driver. Those are generic and have nothing to do with Garmin.

No driver is needed to communicate with the 152H. What you do need is Garmin's free MapSource software. The easiest way to get that install is to install Garmin BaseCamp first. Now BaseCamp will not work with the 152H so you can uninstall it after you've installed MapSource.

The 152H, being a marine unit, is most likely in NMEA mode. You'll need to set it to "Garmin Data Transfer" mode as shown on P15 of the owners manual.

I've got an old gpsMap182 and I connect it up to my PC for updates with just jumpers to the comm port and a jumper to the 12volt pin from the pc's power supply (it's a desktop pc with easy access to the guts). If you're handy with electronic wiring it's pretty simple and the installation manual from the garmin website should give you all the clues. I wouldn't use an AC adapter unless I was confident it regulates the voltage, many are unregulated and if connected to something other than what they were made for may supply too much voltage.

MapSource and others use 9,600 baud by default I believe. My bet is that the 152H can be set to that but I've no idea how. Now NMEA mode defaults to 4,800 baud so that's probably why the 152H is set to that.

BTW I don't know what OS you're using but it's a good idea to check that your USB/Serial adapter is working correctly. The way I do that is to short (with anything else disconnected) pins 2 & 3 on the DB-9 connector and then open HyperTerminal (which your version of Windows may or may not have), open the COM port assigned to the USB/Serial adapter and then type random stuff. It should echo on the screen. This is called a loopback test.

Another thing to try now I know you have a multimeter. The brown and blue wires from the 152H are Rx and Tx (or vice-versa) and you need to connect the Tx line (which has voltage on it) to the Rx line on the USB/serial adapter. Now Rx and Tx on the adapter is on pins 2 & 3. In short the Tx of one goes to the Rx line of the other. To put it another way the signals with volts on them go to the ones without.

PS: Another quick and easy test is to use HyperTerminal (or equivalent) and configure it for 4,800 baud. Then set the 152H to NMEA mode and you should (if everything is connected right) see data appear in the window.

Using GPSU I followed their communications tests and got the software to talk to the GPS!

Excellent! You've got the wiring correct so the rest is just software :D

Yes. In NMEA in/out mode a GPS can accept waypoints. Evidently your 152H is still in NMEA mode. If you can get it to Garmin mode MapSource should work.

LOL

Plus the sun is over the yard-arm where you are. DRINKS!

Only 10:30am here but it's 5 o'clock somewhere :p

5.30 in fact :)

Then you should be on your 3rd by now :p

4th lol