Bringing the VHF indoors question..

MystyBlue2

MystyBlue2

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Hi folks I'm wanting to bring my VHF DSC indoors to "Tinker" and get to grips with all the buttons and settings.

I'm going to bring the boat battery indoors, Make up a power cable with bullet connectors for radio end, 5A blade fuse and crocodile clips to give the radio power.
This will be done WITHOUT the antenna as this is fixed to the boat and cannot be removed so i will NOT be transmitting on land.

Is there anything i should be careful of so i dont ruin the unit? I'm wanting to practice setting up routine messages via DSC and learning to put in co-ordinates correctly.

I could do this on the boat but would mean alot of time just sitting in the boat itself and with a 6 month old baby taking up all my time at the moment after work that is out of the question.
So my plan is to "Tinker" when he is in bed.

Is there a possibility of me blowing the radio up or melting the transmitter internally etc?

Cheers folks.
 
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Most modern radios have an inbuilt protection on the RF output but not having an antenna on the radio you are still likely to blow the power amp in the output stage of the radio.

Radios do not like to be used with miss-matched antennas, best to use a "Dummy Load" of at least the power handling of the radio something like this:
Gam3Gear PL259 Male Plug DC to 1GHz 60W Watt Dummy Load: Amazon.co.uk: Electronics
That would at least allow you to transmit and not send out an actual radio signal, there are various types of connector to plug the dummy load into the back of the radio.
In Decca we used what was called a kilowatt Can, basically a paint tin filled with oil and a large dummy load immersed in the oil to keep it cool.
 
Alicatt said:
Most modern radios have an inbuilt protection on the RF output but not having an antenna on the radio you are still likely to blow the power amp in the output stage of the radio.

Radios do not like to be used with miss-matched antennas, best to use a "Dummy Load" of at least the power handling of the radio something like this:
Gam3Gear PL259 Male Plug DC to 1GHz 60W Watt Dummy Load: Amazon.co.uk: Electronics
That would at least allow you to transmit and not send out an actual radio signal, there are various types of connector to plug the dummy load into the back of the radio.
In Decca we used what was called a kilowatt Can, basically a paint tin filled with oil and a large dummy load immersed in the oil to keep it cool.
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Thank you very much! Lots of info there. ? il look into a dummy. Cheers mate ?
 
MystyBlue2 said:
Is there anything i should be careful of so i dont ruin the unit? I'm wanting to practice setting up routine messages via DSC and learning to put in co-ordinates correctly.
Click to expand...

It's a good plan to get yourself familiar with DSC messaging. It is actually very useful. Ideally your radio should be connected to your GPS and pick up coordinates automatically. If not, the chances of sending the wrong coordinates if la merde hits the ventilateur are rather high.
 
madabouttheboat said:
It's a good plan to get yourself familiar with DSC messaging. It is actually very useful. Ideally your radio should be connected to your GPS and pick up coordinates automatically. If not, the chances of sending the wrong coordinates if la merde hits the ventilateur are rather high.
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Thats my plan in the very near future, To connect my plotter with my VHF so i have use of the big red button if ever needed.

I have no idea where to start with that one and you will probably see a thread on this in the very near future.

Cheers mate ?
 
Whatever you do do not press that big red button even when the set is connected to a dummy load. This is because some loads and/or radios can leak RF when on transmit and this can be enough to cause an alert.

If you have not done your Short Range Certificate yet I can recommend it as all will be explained and you will get a chance to try things on their simulator.
 
seacomm said:
Whatever you do do not press that big red button even when the set is connected to a dummy load. This is because some loads and/or radios can leak RF when on transmit and this can be enough to cause an alert.

If you have not done your Short Range Certificate yet I can recommend it as all will be explained and you will get a chance to try things on their simulator.
Click to expand...
Hi mate i already did my ticket 3 years ago, but with obvious restrictions in place i feel myself becoming a bit rusty with plotter and radio equipment. So i thought I would give myself a refresher in the comfort of my dining room table and become more familiar with the equipment. Will save alot of panic and time if i need to do something out there if my brain has froze and i have forgotten what i learned. And dont worry, I will stay well clear of that big red button . Dont fancy the CG smashing my front door down ?
 
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Given the nature of consumer electronics these days it strikes me that it wouldn't cost much to add a simulator/sandbox mode to a DSC set to allow the curious and the inexperienced the opportunity to use all the knobs and whistles and indeed the big red button without the risk of Dibble knocking on the front door after the MCA have triangulated your position.
 
Yes I see your problem

Like the idea of a simulator mode but I suspect the reason for not having it on your radio is that you may select it in error in a panic situation.

There is of course simulator software you can get for your computer, not tried it but it looks quite realistic and it has the advantage you can press the big red button!
 
Not tried the simulation software either, I was sent from Scrabster to Croydon for a training course in 1973 which involved installing and servicing MF and VHF radios for Decca Radar, the one complaint all of us on the course had was at the end of it we still did not have any formal licence for marine radios.
So there were 2 engineers, a storeman, and myself the trainee, I was the only one that had the training on the radios in our office and the lead engineer had the licence to actually transmit so after installing anything I had to call on him to actually tune the radio up to the antenna under my guidance. :)

I came across this while looking for other simulation software, not got anything from them or tried it but it's a place to start looking: Nautical Software » Boat Training Program » Gain Confidence Afloat with Our Software
 
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