Radio reception inside the boat

[homer2911]

FM is fine, but AM and LW are just one long buzz, whether the engine is running or not. Any way round it?

Edited March 23, 2014 by homer2911

[Idunhoe]

Get an aerial outside the boat...simples

[John Williamson 1955]

Yup,you need an external aerial. It's the same problem that you get with a car. The radio is effectively inside an earthed metal box.

 

Sometimes, you can get a better signal if you position the radio adjacent to a window. Also, the ferrite aerial used for MW and LW is directional, so you need to position it so that it is side on to the transmitter. If it's end on, you'll get no signal at all.

 

(Edit) You will also get a lot of radio interference from the switch mode power supplies used in things like phone chargers and LED lights.

Edited March 23, 2014 by John Williamson 1955

[Ex- Member]

Just rig up a lead to connect your radio aerial to the internal tv aerial socket or lead, assuming you're not watching tv and radio at the same time. Just connecting to the live centre of a tv coax will draw in a decent radio signal.

 

Not sure if this works with DAB though, haven't tried it yet. A wee experiment for tomorrow i think.

[Mike Todd]

Yup - that's what we suffer with. However, even adding an external aerial does not eliminate it either. Perhaps I need to check something about earthing and shielding but, since the run from the outside is coax I'm lost for ideas.

Yup,you need an external aerial. It's the same problem that you get with a car. The radio is effectively inside an earthed metal box.

 

Sometimes, you can get a better signal if you position the radio adjacent to a window. Also, the ferrite aerial used for MW and LW is directional, so you need to position it so that it is side on to the transmitter. If it's end on, you'll get no signal at all.

 

(Edit) You will also get a lot of radio interference from the switch mode power supplies used in things like phone chargers and LED lights.

[John Williamson 1955]

Yup - that's what we suffer with. However, even adding an external aerial does not eliminate it either. Perhaps I need to check something about earthing and shielding but, since the run from the outside is coax I'm lost for ideas.

Car radio systems get round the problem by using an external aerial and having a good connection to the chassis, and paying attention to the screening of the co-ax at both ends of the link, and enclosing the circuitry inside an earthed metal box. As the weather causes corrosion on the connection at the aerial end, so performance drops off, and interference increases. If you're using a normal battery portable set, you're on a loser before you start, even with an external aerial, as all most of them do is connect the external aerial to a coil wrapped round the ferrite rod, which still picks up any interference from inside the metal box which is the boat hull and cabin top.

[OldGoat]

Is there anything left on LW (R4 LW - is repeated on DAB), BUT MW??

I have an external aerial on the boat and we don't even try" low frequencies"

 

Still that's not the question.

 

 

[John Williamson 1955]

Is there anything left on LW (R4 LW - is repeated on DAB), BUT MW??

I have an external aerial on the boat and we don't even try" low frequencies"

 

Still that's not the question.

 

 

If you're talking about MW in Britain, most of the "Gold" stations playing oldies can be found on AM, as can Talksport and 5Live, the BBC's sports channel.

[Southern Star]

Car radio systems get round the problem by using an external aerial

I believe most modern cars use the heated rear window element to receive radio signals.

[mango]

While on the topic of radio reception, is anyone having problems with interference from LED lighting on DAB or FM? It is a fairly common problem in houses.

[Graham Davis]

I believe most modern cars use the heated rear window element to receive radio signals.

 

Generally they still have a roof aerial but use the rear window heater as well. On some Estates they might use an aerial in the rear side window glass. (typically VAG moels)

[KJT]

While on the topic of radio reception, is anyone having problems with interference from LED lighting on DAB or FM? It is a fairly common problem in houses.

Yes I have had that problem with some cheaper LED's I fitted a couple of years ago. Especially when the DAB radio is within about 10 feet of the LED light fitting.

 

I replaced the LEDs with some from 'Baddie the Pirate' and 'Bedazzled' which I believe have some additional circuitry and the 'problem' disappeared.

 

I understand that some of the cheaper LED's emit RF interference which is picked up by DAB radios.

 

Ken

[Daiboy]

I use the tv and freeview for my radio (Magic etc). Plug in some extra speakers aft, job done.

[J R]

Our DAB radio is plumbed into the roof aerial. No probs with reception. A steel boat is effectively a Faraday Cage which prevents signals getting in. Sometimes a radio aerial will work, but depends on where you are and the signal strength.

[mango]

Yes I have had that problem with some cheaper LED's I fitted a couple of years ago. Especially when the DAB radio is within about 10 feet of the LED light fitting.

 

I replaced the LEDs with some from 'Baddie the Pirate' and 'Bedazzled' which I believe have some additional circuitry and the 'problem' disappeared.

 

I understand that some of the cheaper LED's emit RF interference which is picked up by DAB radios.

 

Ken

The suppliers you mention sell LEDs capable of withstanding the high input voltages seen when batteries are on charge and voltage spikes – something that all LEDs should have. I have not seen any mention of radio interference but will check their websites.

 

In home use, 12V LEDs seem to be more of a problem than mains voltage ones. Switched mode power supplies have replaced transformers and can be another source of interference, helped by the connecting leads transmitting interference.

[bizzard]

My Roberts DAB portable works fine with just the telescopic aerial pulled up in my boats window and its not a good reception area around here for anything.

[Arthur Marshall]

I've got a car DAB radio on an ordinary car aeriel with a splitter which should let me get MW and LW as well as FM. FM and DAB work fine, but MW and LW are just masses of interference. Not sure why. LW would be useful for listening to the cricket when there's no DAB reception, but otherwise i can't say i miss it.

[OldGoat]

I've got a car DAB radio on an ordinary car aeriel with a splitter which should let me get MW and LW as well as FM. FM and DAB work fine, but MW and LW are just masses of interference. Not sure why. LW would be useful for listening to the cricket when there's no DAB reception, but otherwise i can't say i miss it.

 

 

Your comment (which bears out why I thought there was nowt on M and LW) together wit ano who said there's lot on LF broadcasts got me thinking.

 

in the days of steam radios with valves and such like stes commonly had a ferrite rod with coils on it in lieu of an external aerial ( I have a pic somewhere of a tuner that I sold recently - but I have to learn how to upload it).

 

Now translating that to modern kit - I suspect that because low frequencies are pervasive; submariners use ultra low frequencies at depth - I suspect that modern car radios have a bit of wire inside them sufficient for L&MW reception. In a car there's sufficient glass to aloow such frequencies to be accessed.

 

Put the whole thing into a boat with fewer areas of glass and the result is 'poor'. There's no way of linking the VHF aerial to the MF stuff anyway.

 

Does that make sense??

[RupertG]

That Faraday shield should be as good at keeping LED/switch noise in as it is in keeping Test Match Special out - using a car radio with an external antenna is probably the best way to go. Many radios with MW/LW only use the external antenna connection for FM/DAB, but that's never true for a car radio - they all use some form of external antenna for all bands.

 

Finding the source - and cure - for radio frequency interference can be a ticklish job. If I had a car radio inside the boat with an external antenna and there was an interference problem on MW/LW, I'd probably get a portable MW radio and move it around, inside and out, to see where the noise was strongest/weakest, turning appliances/lights off and on as appropriate. If there's no interference on the portable when it was next to the external antenna but still interference on the internal car radio, then it's getting in somewhere else - perhaps via the radio's power lines (although car radios are designed to reject that), because there's a bad connection on the antenna lead, or if there's something awry with the splitter.

 

All depends how much time and fun you're prepared to have. Me, I like this sort of thing... and car radios can be surprisingly good receivers. I've used one for long-distance MW listening before now. Amazing what you can pick up after dark.

[Arthur Marshall]

My suspicion is that it's the gizmo that splits the external aeriel into the FM and DAB feeds - it seems to be powered and I had much the same trouble when the radio was in the car and used the same splitter. When I had two separate aeriels fitted, one for FM etc and one for DAb in the car it all worked fine. However, if I disconnect everything except the aeriel to the FM feed, I still can't get MW/LW in the boat, which I used to when I just had a bog standard radio. So I sort of suspect the DAB decoder is mucking up the MW signal... or possibly I need a better radio...