Silva VHF radio - GPS connection help needed

[prv]

What does that output Pete ?

NMEA0183 at TTL level, 9600baud by default but can be configured. I can't remember off-hand what sentences, but certainly GGA as that's what I'm using in my project. Pretty sure all the other common ones were there too.

Fair point that it would also need a max232 module to produce compliant signal voltages - although I've had a similar unit without one happily feeding my Standard Horizon VHF for the last four years or so.

Pete

 

[PaulRainbow]

NMEA0183 at TTL level, 9600baud by default but can be configured. I can't remember off-hand what sentences, but certainly GGA as that's what I'm using in my project. Pretty sure all the other common ones were there too.

Fair point that it would also need a max232 module to produce compliant signal voltages - although I've had a similar unit without one happily feeding my Standard Horizon VHF for the last four years or so.

Pete

I have a similar thing, but USB, using the uBlox GPS. It outputs GGA and a few others. I wonder how it would work with the USB plug chopped off, wired to 5v and NMEA ?

 

[pvb]

For the average boat owner, these things are far too complicated. Most people would find it a nightmare to have to configure one of these cheap GPS devices to output NMEA (and to do it at a sensible baud rate which other bits of kit could accept). OK for those with diplomas in geekery perhaps.

 

[prv]

I have a similar thing, but USB, using the uBlox GPS. It outputs GGA and a few others. I wonder how it would work with the USB plug chopped off, wired to 5v and NMEA ?

About as well as if you cut the BT plug off your telephone, spliced on a Belling connector, and plugged it into your TV aerial.

Pete

 

[prv]

For the average boat owner, these things are far too complicated. Most people would find it a nightmare to have to configure one of these cheap GPS devices to output NMEA (and to do it at a sensible baud rate which other bits of kit could accept).

I've never had to configure one. The first time I got a uBlox module I did download the configuration software and set up the connection - but then found it was already configured as I required by default, and I needn't have bothered. I don't even know what a plausible alternative to NMEA would be.

However, given the neverending stream of numpties unable to figure out that they should connect the output of one piece of equipment to the input of another, I can't disagree that many would find it too difficult nevertheless.

Pete

 

[PaulRainbow]

However, given the neverending stream of numpties unable to figure out that they should connect the output of one piece of equipment to the input of another, I can't disagree that many would find it too difficult nevertheless.

Pete

:ambivalence::eek-new::hororr:

 

[gilesfordcrush]

I had time to look at my VHF setup yesterday, and I've decided to stop mucking about, and get a replacement for the S15 - probably the Standard Horizon GX1700E. In order to locate the new VHF in the best place, I need to extend my aerial cable by about 2-3 meters. Can I do this by using the appropriate BNC connectors and a new 2-3m length of cable, or should I expect the replace the entire cable run to the masthead aerial?

 

[ShinyShoe]

You CAN. You POSSIBLY shouldn't!

So by can I mean it will work and on the surface seem absolutely fine, certainly won't damage the system

**BUT** every mechanical connection on a coax cable causes some loss of power. I've seen -3dB mentioned previously. So you may loose some signal strength etc, you wont notice - till that day you are right on the limit of transmitting power!

I'd expect there should be a "solderable" option that will cause less (but not zero) loss. Beware - loss at 156MHz may be different from 2.4GHz which seems to be a commonly quoted value on fittings. Check the details on the spec sheet...

 

[gilesfordcrush]

Ah, I had an inkling that might be the case! Thanks for the advice. I am quite handy with a soldering iron, so I could certainly extend the cable that way, but how would I know if I had compromised the signal?

 

[lpdsn]

Ah, I had an inkling that might be the case! Thanks for the advice. I am quite handy with a soldering iron, so I could certainly extend the cable that way, but how would I know if I had compromised the signal?

Maplin are doing RG58 cable at £1.49 per meter. http://www.maplin.co.uk/p/coax-rg58-50andohm-cable-black-priced-per-metre-xs51f

You can probably beat that price, or if you wanted to spend more find a cable with a lower attenuation. It's probably as easy to run a new cable as to mess around soldering.

 

[ShinyShoe]

Now that my brain is engaged...

You said new cable up the mast. What happens at the bottom of your mast? It wouldn't be unusual to have some form of fitting on the base that lets it into the hull. If there was you'd possibly only be cabling back to that...

Or how do you unstep the mast?

 

[gilesfordcrush]

I'll have to check how the cable runs from the bottom of the mast, I think it runs straight through, I'll see.

Soldering is easy peasy, so I'll probably extend the cable by a metre or two for the time being, and then as and when I'm ready for more long distance cruising I'll upgrade the antenna and replace all the cable.

I'm ordering the new VHF today.