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I hope to replace the AM/FM/Cassette player in my boat with an AM/FM/Digital media player. When reviewing the owner’s manual prior to purchase I noted that the installation instructions call for two sources of power: one wire to an ignition or accessory circuit and another wire directly from the positive terminal on the battery. These instructions are for installing the player in a car and the wire that would come from the ignition or accessory circuit on a car will come from the switch for the AM/FM radio on the panel board on my boat and will be protected by an in-line fuse. My concern arises from the wire directly from the battery which provides power for the clock, calendar, and, perhaps, memory presets, etc. Specifically, would these loads significantly deplete the battery from which the power is to be drawn? My intuitive sense is not to worry about it; after all, the battery drain is not a problem when installed in a car. Is there any reason to think otherwise? I suppose that this wire should be protected by an in-line fuse located as close to the battery as possible.
 

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Sea Dweeb
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The third wire is to keep power to the microprocessor and memory. The system in your automobile is pretty much the same. It should draw only a few mils. It will have similar probability of depleting the battery as your automobile does if left parked for the same period of time.
 

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Yellow is memory...red is power...If you do NOT need FM memory presets...simply wire BOTH the yellow and red to the same switched circuit breaker. The amp draw on memory is typically milliamps and if you see your boat once a month or so you should not have anything to worry about.
Some stereos feature a built in clock that is always on and these tend to draw about .2-.5 amps and can draw down much more quickly...so figure that out before you decide what you want to do.
 

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Telstar 28
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I'd point out that some stereos will keep the memory presets without any power and only need the "memory wire" for the clock.
 

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Funny that this came up now. I just did the same type installation on my boat. I used the wiring from the old stereo to hook up the new Stereo. It worked great until I started up the engine. With the engine running I switched on the stereo and it blew the .5 Amp fuse that was in line on the yellow wire. A friend suggested using a 1 amp fuse instead. I did this and it solved the problem. Is this a good idea? The new installation instructions didn't even mention putting in a fuse on this wire.
Anyone care to comment?
Bruce
 

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cam's post pretty much covers it.

Unless you really feel like you want the station presets and other functions that require the constant source of power, just wire both to the circuit breaker. Since it sounds like you're interested in using digital media anyway, my guess is the station presets aren't that big a deal.
 

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"blew the .5 Amp fuse that was in line on the yellow wire. A friend suggested using a 1 amp fuse instead. I did this and it solved the problem. Is this a good idea? "
In a word, no.
Either something was set up wrong in the installation, or the maker screwed up in shipping a 1/2A fuse. If the problem is the installation, you'd want to know what that is and fix it properly. If the problem is the maker...You'd still want to know if you can trust the radio not to catch fire sometime from another problem.
Sometimes, some very rare times, fuses are defective and they simply blow. The vast majority of the time, they blow because something is WRONG and putting a penny in the fusebox (or a higher rated fuse) is simply a good way to make the wire it was protecting overload and catch fire.
Odds are you can get away with it, but do you want to play the odds at all?
 

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Funny that this came up now. I just did the same type installation on my boat. I used the wiring from the old stereo to hook up the new Stereo. It worked great until I started up the engine. With the engine running I switched on the stereo and it blew the .5 Amp fuse that was in line on the yellow wire. A friend suggested using a 1 amp fuse instead. I did this and it solved the problem. Is this a good idea? The new installation instructions didn't even mention putting in a fuse on this wire.
Anyone care to comment?
Bruce
Bruce...what make and model is your new stereo? Is the fuse that blew one from your old stereo or the one that came on your new one? Is the RED wire on your new one fused out of the box or are you using the old red wire? If the red wire on your new stereo was fused...what is the amp rating of the fuse? Generally you are gonna need a 5amp or 10amp (depending on the radio) fuse on either the red or yellow depending on how they are used by the partiuclar manufacturer. In the meantime...the 1amp replacement fuse should not hurt anything as LONG AS the yellow wire with the fuse on it is from the old radio.
 

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Cam,
The Stereo is a DUAL MXCP66 AM/FM/USB CD Stereo from West Marine. The fuse that blew was from the old stereo. The new one did not call for any fuse on the Yellow wire. There is a 10 Amp fuse in the back of the new stereo. Since it is part of the stereo I have no way of knowing which wire it is fused to. The old stereo had a fusebox that had both the red and black wires coming from it. Rather than take that off I ran my new wires to those so I have an extra fusebox that wasn't called for but I don't know what size fuse that is.
From this message you can tell that Electricity is not one of my strong suits, so I appreciate the help.
Bruce
 

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OK Bruce...that is easy. Both yellow and red are protected already by the unit. You may still wish to use fuses closer to the battery on BOTH wires as a fuse ON the unit is not the best fire prevention. If you choose to add fuses they should BOTH be rated at 10 amps.
I would reiterate...this is YOUR choice. The unit is already protected. I would get rid of the 1amp fuse in any case.
The blue wire should be taped off and not used.
Note that the yellow will put a full time drain on your battery if you wire it direct. It is a very small current used to keep your stations in memory. If you do not want that drain....wire the yellow to the switch where you have the red and forget about station memory.

Enjoy.
 

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cam-
"If you choose to add fuses they should BOTH be rated at 10 amps. "
How do you figure that? Fuses are intended either to protect a device (which is why there is a 10A fuse immediately behind the radio) or to protect wires from overload. If the red and yellow wires are fused, those fuses should be chosen based on the wire guage, i.e. the "allowable carrying capacity" of the wire, or the maximum load that would normally be placed on them, whichever is lower.
In the case of the memory-keep-alive circuit, one amp is more than it should need to run the clock and memory, so a 10A fuse would be excessive. It might still protect the wire--but if more than 1A is being drawn, that's probably already time to blow a fuse and prevent the problem from getting hotter.
In the case of the red main power wire...the same 10A that protects the radio is probably correct, assuming the wire can handle ten amps at 14.4VDC. If the red wire is at least 20AWG, it should be fine with a 10A fuse. (Although 20AWG might have excessive voltage drop.)
But fusing the fuses, leaving them installed in series? Uhuh, someday that's gonna come back to waste someone's time when they can't find "the" blown fuse and never suspect there's more than one of them.
 

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HS...first...the red and yellow wires are the same gauge. (If memory serves, they are either 16 or 18 gauge) The radio is protected from excess current on either one. The purpose of fusing the individual wires close to the battery would be to protect the wires from overheating and possiblly becoming a fire hazzard. I think the idea of putting the fuse in the radio is REALLY a bad idea. They belong as close the the battery as possible. Agreed?

The yellow wire these days often carries not ONLY the memory circuit but also the full current used by the radio with the RED only acting as a switching circuit. There is no specification for which does which on this radio...so my thought is to err on the safe side. The unit is obviously protected and at least one of the wires is designed to carry 10amps and since the other is the same size, I felt comfortable with that. In operation, the radio is unlikely to draw more than 4-5 amps.

I agree with you about "someday" somebody blaming that fool Camaraderie for a Rube Goldberg solution. Nevertheless...it is Dual with the stupid solution that leaves the power wires exposed to overheating in a MARINE stereo. :D
Make sense to you?
 

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Cam,
The Stereo is a DUAL MXCP66 AM/FM/USB CD Stereo from West Marine. The fuse that blew was from the old stereo. The new one did not call for any fuse on the Yellow wire. There is a 10 Amp fuse in the back of the new stereo. Since it is part of the stereo I have no way of knowing which wire it is fused to. The old stereo had a fusebox that had both the red and black wires coming from it. Rather than take that off I ran my new wires to those so I have an extra fusebox that wasn't called for but I don't know what size fuse that is.
From this message you can tell that Electricity is not one of my strong suits, so I appreciate the help.
Bruce

How do you like that Dual MXCP66? I've been thinking about picking it up but I've been a little skeptical because of the low price. Is it a quality unit?
 

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cam-
"...The purpose of fusing the individual wires close to the battery...putting the fuse in the radio is REALLY a bad idea."
But there are two legitimate purposes, two different things being protected. Fusing the power distribution wires (at the battery or power panel) is a fire protection. Fusing a device, at the device, is to protect the device itself. From inductive surges, from folks who've added "too much stuff" and put too heavy a fuse on a shared power line, and so on.
Both can be legitimate, although the redundancy can be less than ideal. (I've met circuits in cars that use fuses in series, and that's the way that the car makers design them. i.e. one under the hood to protect all the "dash" circuits, and then more under the dash to protect each sub-circuit.)

"The yellow wire these days often carries not ONLY the memory circuit but also the full current used by the radio with the RED only acting as a switching circuit." I didn't know that. If that's what you are anticipating, then by all means go for it. Of course, confirming the proper specs with the radio maker 9or an ammeter) might be the safest course. these days, there is no telling what some engineer thought they were doing, and that's before the "forensic engineers" get into the picture and start REMOVING components to knock down the production costs before stuff goes to manufacturing. There actually are such evil beings, they're the reason why there are often empty slots on circuit boards. I think they should be required to give up one eye, one arm, one nostril, one lung, and one kidney before being allowed to pursue that career path, though. Oh, and one butt cheek too.<G>

"Make sense to you?" About the only thing that makes sense to me these days, is that the French invented the champagne cork to assure they could tap into the good stuff even if no one remembered to bring along a corkscrew.

But then again, I still prefer a tuning DIAL on a radio, so what do I know?
 

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Telstar 28
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Junk...go with a decent unit from Alpine, Sony, Pioneer, or one of the other known manufacturers.
How do you like that Dual MXCP66? I've been thinking about picking it up but I've been a little skeptical because of the low price. Is it a quality unit?
 

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How do you like that Dual MXCP66? I've been thinking about picking it up but I've been a little skeptical because of the low price. Is it a quality unit?
That sounds like the model I got back at Christmas time. ($99.00) It is a 200 watt system that only comes with two 60 watt speakers so you have to buy two more to get the 200 watts - 50 watts/channel. The speakers that come with it are marine speakers but are not sheilded so you have to place them well away from any electronics and navigation equipment. I bought two extra Dual speakers that were 150 watts and had the sheiled magnets for closer to cockpit placement, the oem ones were positioned up at the V-berth for minimal interference. With four speakers the full 200 watts is enough to chase you out of the boat when cranked up. Not a bad unit for a small boat like mine and I can hear it clearly from the cockpit. The price is right and it works with my iPod through the Aux with a jack in place of the headphones.
 

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Capn Kermie...while you may be happy with your radio...it may surprise you to know that it does not even put out one fifth of the power rating you refer to and which they print on the box.
Speaker POWER HANDLING ratings have nothing to do with the wattage of the unit.
The speakers suck and you've blown out your eardrums with the IPOD so you don't notice! :D :D :D
 
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