car radio for boat

I'm always amazed at the rubbish systems on boats. Ours is 1500w and sounds great for a few miles away.Get a normal stereo but get really good speakers and amp.
 
I was wondering this morning why one of my batteries sems to be losing power compared to the other one, and yes, the previous owner had run a (hard to notice) wire I traced back to the radio. (JVC 4x50) Why NV memory is not used beats me. Even on a car infrequently used, it must pose a bit of a problem. I'd disconnect if I had a tuning dial, but the faff of 'scanning' every time to find R4 would be a nuisance. I wonder if any DC wizards can come up with a solution. I'd happily replace a dry cell battery once a season if that'd do the trick.:(

The battery problem may be unrelated to the radio, but if the radio has a significant parasitic draw to keep the memory active and that draw is effecting a large storage battery then any small battery, like a dry cell ,will be drained quickly and wont be effective..
As a first step I would measure the draw. A dc clamp multimeter can measure this without even having to disconnect any wires.
If the drain is significant the only options are to disconnect and loose the presets,(perhaps only when you leave the boat for long periods) buy another radio with a lower draw, increase the battery capacity or replace the power with say a solar panel.
 
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Wiring permanently into one of the batteries as long as it's via an inline fuse shouldn't cause a problem. It doesn't with cars and they generally have less capacity in their battery.
You might want to think about DAB as the analogue signal is supposed to be getting turned off in a few years but that is another debate.
 
One of the main reasons for switching off the master switch is to avoid flattening the battery from the small power drain from things like the memory function in the stereo.
If you want to avoid the loss of memory you can connect the stereo directly to the battery (or the memory function only if you want), but check the drain first. It varies a lot between stereos and can be enough to make an impact on the batteries if you are away a long time and have no charging.
The marine units behave the same. Most are simply car units with slightly better seals and a sprayed circuit board. Fusion is about the only exception. None I know of have a non volatile memory that doesn’t require power.

i have the stereo memory,bilge pump & navtex on permanent supply with no ill effects.
shore power is never left on un-attended
 
i have the stereo memory,bilge pump & navtex on permanent supply with no ill effects.
shore power is never left on un-attended
There is a big variation in the current draw for the stereo memory circuits. Many will not cause any problems at all. There is also a big variation in how often boats are used and the batteries are recharged,
The best recommendation is to measure the current draw and together with the battery capacity and the length of time between recharges it is possible to determine if there is likely to be an issue.
I agree in many cases it is fine to leave the memory circuits active, but it can cause battery damage in some cases. In all cases the power needs to be replaced so it is worth considering if the benefits outweigh the power draw.
Units with remote control as an option (not necessarily supplied as standard) seem to have a particularly high standby power draw. The circuit that is watching for a possible remote control signal to wake the unit draws some power.
 
There is a big variation in the current draw for the stereo memory circuits. Many will not cause any problems at all. There is also a big variation in how often boats are used and the batteries are recharged,
The best recommendation is to measure the current draw and together with the battery capacity and the length of time between recharges it is possible to determine if there is likely to be an issue.
I agree in many cases it is fine to leave the memory circuits active, but it can cause battery damage in some cases. In all cases the power needs to be replaced so it is worth considering if the benefits outweigh the power draw.
Units with remote control as an option (not necessarily supplied as standard) seem to have a particularly high standby power draw. The circuit that is watching for a possible remote control signal to wake the unit draws some power.

Boat has been ashore the past 4 months all memory running + navtex with no mains battery charging but we do have a wind genny
 
If you unleashed 4x50 watts of audio in a boat battery life would be a minor problem, you would almost certainly damage your hearing.

The makers quote huge power levels to impress silly children who in turn use them to impress their equally silly mates.

It also helps the amps operate over a linear portion of their power curve supposedly giving better quality sound.

Just keep the wick turned down to a comfortable level
 
Boat has been ashore the past 4 months all memory running + navtex with no mains battery charging but we do have a wind genny

Even a small wind generator in a sheltered location is likely to be putting more power into the batteries on average than the stereo memory and navtex are taking out, so your batteries should remain fully charged while the boat is ashore.
 
If you unleashed 4x50 watts of audio in a boat battery life would be a minor problem, you would almost certainly damage your hearing.

The makers quote huge power levels to impress silly children who in turn use them to impress their equally silly mates.

It also helps the amps operate over a linear portion of their power curve supposedly giving better quality sound.

Just keep the wick turned down to a comfortable level
As you say the power levels quoted are a bit silly, but our ears respond to sound in a logarithmic fashion so while even loud music may not be much more than 1w on average the peak sound level will be much louder, many hundreds of watts for a short period. An amplifier needs to able to deliver these short burst of power, without distortion and the RMS continuous rating is probably the best measure of its ability to do so. A high rating (If its accurate ) will generally mean better sound even at low volumes.
The high power rating is less likely to damage your speakers and hearing than an amplifier that is clipping.
 
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I just fitted a new radio in the boat - the last one lost it's digital display.
It cost £40 'new' on eBay but came without instructions. It was an unboxed customer return. Got a discount from the seller and bought a set of instructions on the internet.

My main criteria for choosing the radio was that long wave was a must.

I was not concerned how many bells or whistles it had on it or what the standby current was. (have wind generator and solar panel)

I ended up with a Goodmans GCE 7205USB2 which is an all singing and dancing thing.
It has 4 x 20 Watts RMS output and can consume up to 15 Amps.

I only use two of the speaker outputs and it is unlikely to draw even one amp at the volume levels I will use.

The main thing is it seems to be much more sensitive and selective than the previous radio and even has push buttons for station selection. It also has medium and long wave.

If the powers that be decide to change the modulation techniques to make the radio redundant in the future it will be no great loss. But that will be many years away at the present financial state of the country.
 
There is a big variation in the current draw for the stereo memory circuits. Many will not cause any problems at all. There is also a big variation in how often boats are used and the batteries are recharged,
The best recommendation is to measure the current draw and together with the battery capacity and the length of time between recharges it is possible to determine if there is likely to be an issue.
I agree in many cases it is fine to leave the memory circuits active, but it can cause battery damage in some cases. In all cases the power needs to be replaced so it is worth considering if the benefits outweigh the power draw.
Units with remote control as an option (not necessarily supplied as standard) seem to have a particularly high standby power draw. The circuit that is watching for a possible remote control signal to wake the unit draws some power.

Scanning a few manufacturers sites it seems almost impossible to get current draw data for either normal or standby operation prior to purchase; can't see Mr Halfords being too helpful either.
 
I measured the currents today.(Goodmans GCE 7205USB2)

Standby radio off 23mA (ie memory feed)


Radio on at the volume I had left it at (playing music on Classic FM) 75mA (ie 0.075A) at a battery voltage of 13.8


I was most surprised.

Iain
 
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I have fitted 3 or 4 different car CD/radios and each one has the same feature that it looses the station tuning when the powere is off. Like most people, Iturn of the battery master switch when I leave the boat.

I would be interested to know if so-called 'marine' domestic radios suffer the same way. I suspect that they do.

Ian

The radio will have a seperate memory power feed. Wire this to your bilge pump power line using a very low value fuse in line. That way you will keep your memorised stations when you turn off your battery.
The memory uses a trivial amount of power.
 
The 15watts audio will probably mean peak power which is obtained on sustained bass notes.
The actual average electrical consumption will be an amp or so. If you believe everything that is written about hi fi systems you would have massive cables to massive speakers to give that oh so smooooooooth bass sound.
On a practical note,most car radios lose their push button station selection when the power is switched completely off . In a car, this is maintained with a constant 12V which is not wired through the ignition switch.. That can be a nusiance but I believe some more modern radios have non-volatile memory to deal with this
 
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The memory uses a trivial amount of power.
This is true for some units, but not all.
Even when the memory consumption is relatively low, the small amounts of power can add up to be significant if you leave the boat for a long time.
Measure the consumption and consider if it will be important in your installation. A switch that allows you to retain the memory, or not, is often a good solution and is how I have wired up my boat.
 
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