GPS signal to DSC VHF

GrowingLad

GrowingLad

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Just thought I'd post this up as I had a bit of a job trying to find the information required on the web, so if I put a post up here other peeps on the interweeb might find the below helpful.

I've got a separate GPS receiver that connects to my laptop via a USB connection to supply GPS data to my Garmin chart plotting software.

I've recently bought a DSC VHF radio that required a GPS input.

Now I was using Franson GPSgate to translate the GPS signal from the receiver to the Garmin software.

I configured the Franson GPSgate to also have the serial RS-232 as an output. I configured it with a speed of 4800 baud. I also right clicked on Mycomputer to management / Device Management / Ports (COM & LPT) right clicked on properties of COM1 and checked the baud rate.

I then had a D9 connector (if you can get hold of a Blue Cisco console cable it makes the job a bit easier)

I used a continuity tester to find the cables for pins 3 and 5.

My radio is a ICOM 411 with a kind of coaxial cable.
The outer conductor is NMEA - (common)
The inner conductor is NMEA +

You need to connect Pin 3 of the D9 serial RS-232 to NMEA + (inner cable of the radio)
and Pin 5 of the D9 serial RS-232 to NMEA - (outer cable of the radio).

If your machine doesn't have a serial RS-232 you can get a USB to Serial converter for around 10-20 quid. I've used these a lot in my job and have very rarely had a problem.

Had my laptop/GPS, VHF radio and 12v car battery out on the balcony last night and got it all running sweetly. I had read somewhere to use pin 2 instead of pin 3 but this doesn't seem correct to me as mine was working with pin 3 and 5.

I hope someone finds the above useful.

GL.
 
GrowingLad said:
Just thought I'd post this up as I had a bit of a job trying to find the information required on the web, so if I put a post up here other peeps on the interweeb might find the below helpful.

I've got a separate GPS receiver that connects to my laptop via a USB connection to supply GPS data to my Garmin chart plotting software.

I've recently bought a DSC VHF radio that required a GPS input.

Now I was using Franson GPSgate to translate the GPS signal from the receiver to the Garmin software.

I configured the Franson GPSgate to also have the serial RS-232 as an output. I configured it with a speed of 4800 baud. I also right clicked on Mycomputer to management / Device Management / Ports (COM & LPT) right clicked on properties of COM1 and checked the baud rate.

I then had a D9 connector (if you can get hold of a Blue Cisco console cable it makes the job a bit easier)

I used a continuity tester to find the cables for pins 3 and 5.

My radio is a ICOM 411 with a kind of coaxial cable.
The outer conductor is NMEA - (common)
The inner conductor is NMEA +

You need to connect Pin 3 of the D9 serial RS-232 to NMEA + (inner cable of the radio)
and Pin 5 of the D9 serial RS-232 to NMEA - (outer cable of the radio).

If your machine doesn't have a serial RS-232 you can get a USB to Serial converter for around 10-20 quid. I've used these a lot in my job and have very rarely had a problem.

Had my laptop/GPS, VHF radio and 12v car battery out on the balcony last night and got it all running sweetly. I had read somewhere to use pin 2 instead of pin 3 but this doesn't seem correct to me as mine was working with pin 3 and 5.

I hope someone finds the above useful.

GL.
Click to expand...

A good description of how to get a NMEA output (GPS in your case) from a laptop serial bus, BUT do you really want your critical DSC GPS signal to be dependant on the laptop ? :eek:
 
I'm sure many will find this invaluable, however to an old geezer like me I feel like sayimg 'stop the world, I want to get off.'
 
Playtime said:
A good description of how to get a NMEA output (GPS in your case) from a laptop serial bus, BUT do you really want your critical DSC GPS signal to be dependant on the laptop ? :eek:
Click to expand...

Granted if you are doing some serious sailing far from land then perhaps you'd want something a bit more substantial.

For the area I operate in and for the conditions I will put to sea (have a little nine month old) it's more of a case fire has broken out and I need to hit the red button..I may not have time to send a proper mayday before abandoning ship.

For me on a motor boat with my laptop tucked away just inside the cabin..If my laptop has failed I'm in some very very serious do do. I'd have sent a mayday long before the laptop has died.

Fully understand it may not be for most but if you are looking to do something similar it works.
 
GrowingLad said:
Just thought I'd post this up as I had a bit of a job trying to find the information required on the web, so if I put a post up here other peeps on the interweeb might find the below helpful.

I've got a separate GPS receiver that connects to my laptop via a USB connection to supply GPS data to my Garmin chart plotting software.

I've recently bought a DSC VHF radio that required a GPS input.

Now I was using Franson GPSgate to translate the GPS signal from the receiver to the Garmin software.

I configured the Franson GPSgate to also have the serial RS-232 as an output. I configured it with a speed of 4800 baud. I also right clicked on Mycomputer to management / Device Management / Ports (COM & LPT) right clicked on properties of COM1 and checked the baud rate.

I then had a D9 connector (if you can get hold of a Blue Cisco console cable it makes the job a bit easier)

I used a continuity tester to find the cables for pins 3 and 5.

My radio is a ICOM 411 with a kind of coaxial cable.
The outer conductor is NMEA - (common)
The inner conductor is NMEA +

You need to connect Pin 3 of the D9 serial RS-232 to NMEA + (inner cable of the radio)
and Pin 5 of the D9 serial RS-232 to NMEA - (outer cable of the radio).

If your machine doesn't have a serial RS-232 you can get a USB to Serial converter for around 10-20 quid. I've used these a lot in my job and have very rarely had a problem.

Had my laptop/GPS, VHF radio and 12v car battery out on the balcony last night and got it all running sweetly. I had read somewhere to use pin 2 instead of pin 3 but this doesn't seem correct to me as mine was working with pin 3 and 5.

I hope someone finds the above useful.

GL.
Click to expand...

I might be missing something but it seems a complicated set up. I had a DSC radio receiving NMEA data from my GPS receiver. I needed NMEA data for my laptop software so cut into the cable between the GPS and dsc radio tapped on 2 new wires to the existing 2 and connected them to an RS232 plug.
I think you can run up to 4 listeners from one talker (gps receiver) before you need anything more complicated.
 
Spyro said:
I might be missing something but it seems a complicated set up. I had a DSC radio receiving NMEA data from my GPS receiver. I needed NMEA data for my laptop software so cut into the cable between the GPS and dsc radio tapped on 2 new wires to the existing 2 and connected them to an RS232 plug.
I think you can run up to 4 listeners from one talker (gps receiver) before you need anything more complicated.
Click to expand...

This is interesting..although I'm not too sure I want to cut into the wire from my GPS receiver. It connects to my laptop with a USB connection..so I assume it's taking it's power from the laptop. Which in my case if the laptop did die I've also lost my GPS.
 
Spyro said:
I might be missing something but it seems a complicated set up. I had a DSC radio receiving NMEA data from my GPS receiver. I needed NMEA data for my laptop software so cut into the cable between the GPS and dsc radio tapped on 2 new wires to the existing 2 and connected them to an RS232 plug.
I think you can run up to 4 listeners from one talker (gps receiver) before you need anything more complicated.
Click to expand...

I think you are missing something - the GPS connection is USB and the radio needs NMEA. As stated earlier, though, I don't like the laptop in the circuit to the radio. :(
 
reginaldon said:
I'm sure many will find this invaluable, however to an old geezer like me I feel like sayimg 'stop the world, I want to get off.'
Click to expand...

My feelings entirely.

There seems to be an awful lot of unnecessary complications on some people's boats. I go sailing.
 
I quite agree - the DSC red button to be used in an emergency needs to be as simple as possible ... putting a Laptop in the circuit is dodgy at best ... Software will and does crash. Hard Drives will stop working - I know - because I work on them all day.

What is needed is a GPS mushroom (like this one: http://www.thegpsstore.com/Garmin-GPS17X-HVS-NMEA-0183-P1961.aspx but preferrably not that price! Prob find one on Ebay... ) that can be installed and operates independantly of the laptop - it has it's own 12v supply - the USB GPS isn't an option .... The NMEA GPS mushroom pushes out at 4800baud and can be connected DIRECTLY to the VHF (and T'd off to other devices as well).
 
I agree with others. You need to keep it simple. After all, the only time you really need GPS input is when you press the red button and a laptop in the middle is a recipe for disaster.
I suggest to get hold of a cheap 2nd hand GPS such as this, and hard wire it to a 12V supply and the radio.
 
NormanS said:
My feelings entirely.

There seems to be an awful lot of unnecessary complications on some people's boats. I go sailing.
Click to expand...

Maybe it may seem that way, for me computers are my bread and butter.

I think I need to set the record straight. I don't venture across Oceans. I pop along the coast, drop the hook and do a spot of fishing, snorkelling or just laze in the Sun.

If it's forcast force 5 or above then I won't even bother venturing out.

The only time I can really see me needing (although I hope I never have to face such a situation) is a fire (She's a petrol motor boat). In which case I'd need to hit the DSC. Either way, even if the laptop as suffered some kind of failure no problems as the radio will still hold it's last co-ordinates.

Granted, this isn't an option for serious cruisers etc...

For someone like me on the Med who pops out for the day when it's nice and has the same set up with a laptop and a DSC radio then they might find my post useful. It may sound complicated but it's just a cable and a bit of simple software.

And as I said before, even if the laptop was to die....lets say a Tsunami has just come crashing over the transom but yet I've managed to survive the radio will still hold the last co-ordinates.
 
The KISS principal

Just keep it simple and then when you press the RED button it works .. You don't have to wait for the PC to power up as the boat burns .. The more you add the more goes wrong .. I bought a GPS with all the cables etc off ebay .. Cost me £20 ..
 
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