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I love getting away from it all but still like to have some of the comforts of home with me. In restoring the RV, I added some comfort features and want to share some of these ideas.

I’ve no air conditioning in my motor home and yup, it can get uncomfortable. I recently added Fan Tastic powered vents and they work great but before those I used a DC powered fan from a company called 02 Cool. As nice as the new roof fans are, this one is still quieter. That and it is cheap as all get out and does a great job moving air.

fan.jpg

You see there is a little power plug on the side next to the two speed switch. This fan has a base that will take batteries or you can get an AC adapter but I camp mostly places that have no power and I already have the coach battery. So I found these plugs on Amazon. They are simple to wire up and marked plus and minus for center and outside. They also fit a ton of stuff.

plug.jpg

I'm a huge fan of music but not a fan of radio. I carry all the music I listen to on my phone so I wanted something simple and efficient to drive a couple of speakers. This little amp is all over the internet and is cheap. It get all kinds of good reviews even by some audio snobs. Also plugs into 12 volts and the plug, yup it fits.

amp.jpg

Add a couple good little speakers to this thing and you can rock the RV. It won't get stupid loud but will run for hours at pretty low consumption. I connected it to a couple old ADS speakers. These were not the most efficient speakers to power but this little amp does a great job other than more power would help the bottom end but at the cost of power draw off of the battery. A very good compromise.

speaker.jpg

My wife likes to watch TV. I'm not a fan but it is her RV too. I picked up this Visio television that has a external power supply that just happens to be 12 volts. And you guessed it, same power plug.

tv.jpg

So in addition to adding a cigarette lighter port or maybe some USB charger ports to your RV, why not find devices that you want that will work directly off of 12 volts. I have a bunch of other items including a small auto vacuum and even a 12 volt travel wireless router that we use to connect all our wifi devices.

tv_power1.jpg

I found this to be a great alternative to using an inverter which is not the most power efficient way to go with the devices above. I would be using 12 volts DC to convert to 120 volts AC only to use that to convert back to 12 volts DC. This way I am able to have a few comforts while in the middle of nowhere powered off of my coach battery

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Having to stay connected with everyone all the time. I have had to add a bunch of 12v plug ins This year 4 high power USB ports were added. Now my Endless Brezze fan works every where and so do the tablets/Kindles.

I never realized how poor we were with a single 12v outlet with a spliter plugged in.

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I dismantled a high line set of computer speakers by passed the 120V power supply so I could run them on 12 volts. The powered sub gives me outstanding bass and the small speakers fill in the rest. I fell across a Sirius radio with life time subscription in the box for $85 got all the music I'll ever need! It's really nice I get the music I like any where.

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I dismantled a high line set of computer speakers by passed the 120V power supply so I could run them on 12 volts. The powered sub gives me outstanding bass and the small speakers fill in the rest. I fell across a Sirius radio with life time subscription in the box for $85 got all the music I'll ever need! It's really nice I get the music I like any where.

I tried out a Cambridge Soundworks set of sub and cubes in the RV before I swapped it out for this setup. I found I didn't like the top end on those little cubes. You are right about the bass though. I tossed the sub under the couch and it did a pretty sweet job on the low end. This particular set had power input for both 120AC and 12DC. Same plug too wouldn't you know.

The biggest point I'm trying to make is that many of these devices actually function off of DC and use AC power bricks because that is what is in our houses. It just seems very inefficient to use an inverter to power these kinds of devices. So I just found what I wanted that would work off of the 12 volt battery. A bunch of the beach sites we camp at have no power, so I wanted to be sure we could get an extra long weekend off of just the batteries.

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@Back East Don - I'm a bit clueless when it comes to knowing if something runs 12 volt like your Visio. How can you tell? Which model is it, did it have 12 volt/DC listed on the features list? Usually I only see the Naxa, Axess and Skyworth brands and I haven't read that many great reviews on them.

I also don't quite understand how you use that plug from Amazon to connect to your O2 Cool fan especially when that plug portion doesn't look like it would fit in the 12 volt plug of an rv? I know I'm missing something really obvious.

I think you are right on about having devices that run at 12 volts rather than 120 and an inverter. I just wish I understood this better.

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TV's are becoming increasingly harder to find with external power supplies like the one I installed in the RV. That said, the way you tell what the voltage and polarity of most devices is usually the really tiny label (I wish they'd stop that) on the power supply or often on the device itself at the DC input plug.

Lets start with the simple one, the fan. On the fan next to the plug it has a little label saying 12vdc, 500mA with a picture above that shows the outer portion of the plug ring as the - (minus or ground) and the inside center as + (positive). The plugs I bought at Amazon match and are also marked. Center is + and outside ring is -. In my case I ran some two conductor lamp cord. You can get that at home depot. It is very flexible and you'll notice there is one side that is ribbed. I use this side for the ground connection and the other the positive. The connections are held in place by the screw terminals. I wired it directly into the DC section of my power center along with a few other devices. In fact I ran the wiring to a few locations so that I could use the fan in the window near the sink, dinette (couch is there right now) and berth. I just plug in and turn the fan on. What I like about this particular fan is even on high speed, its current draw is only about a half an amp which is very little for the amount of air it moves. Hope this is making sense.

fan_02.jpg

Now the TV. This is more complicated because I had to find it first. I also installed it a couple years ago (yes I know, I'm just getting caught up now with sharing). I shop online quite a bit including a site called Woot. They often have various refurb items and I had been looking for a TV because the wife wanted it. One day they had several different sizes and when looking through the pictures, I noticed there was an external power supply on this one. Still, that meant nothing. I had to go to the Visio web site and download the manual. In the specification it listed the voltage as 12 volts and I was good to go. As I type this, I already feel like I'm not helping. If you want to do something similar, here is what I would suggest. Hit some of the big box stores like best buy or walmarts and look at the small TV's on display. See if any have an external power supply. Bring your reading glasses cause the labels are going to be small. Here is the one for the Visio. Notice just like the fan, it lists the output of the power supply as 12V (it should say DC but the solid line with the dashed line below indicate DC) and 4.58 A.

tv_power2.jpg

In the end, you might be stuck either buying a no-name just to get a DC powered TV or going the inverter route. My post was more about thinking in terms of the most power efficient way. It's the holiday tomorrow and I've family coming. We are having a camping get together in my back yard. Seems like the only way I'm going to be able to camp these days. If I have time next week, I'll do a bit of searching and will see what I can find. Who knows, maybe there is still something out there. As a refurb this Visio was really cheap. Perhaps some others might chime in with something that will work.

Quick addition and question. What size range?

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A quick search found a series of LG TV's with external power supplies but there is a problem. They are 19 volt not 12 volt.

lg_tv.png

This brings up an interesting question. What if one wants to use a device that is not 12 volts. There is a solution to this problem that is also much more energy efficient than going the inverter route. For instance I would like to upgrade the wireless router in the RV but most now run off of 5 volts. I could make a simple IC voltage regulator circuit but these dissipate excess power in the form of heat and are by nature not very efficient. What if, like in the case of the LG TV above, I want to run a device that requires higher voltage?

The solution is a buck converter. These are available on the web including Amazon and come in up convert and down convert. They are typically a small PC board with an input and output and are either programmable or have a simple adjustment mechanism. You just have to pick the appropriate one for converting higher or lower voltage and selecting one that has enough current output to drive the device.

You can find smaller current ones starting at less the $6. Here is one from Amazon that is about $16. It is rated for 6 amps and will take an input between 4.5 - 45 volts and output anywhere from 5 - 60 volts. Rule of thumb is select one that will output about double the current needed for the load. Most of these do however require you have and know how to use a multi-meter to adjust it but once they are set, they are good. The down converters work similarly except require the input voltage be higher than the output. These circuit boards are small and can, in the case of a TV on the wall, be mounted by double sided foam tape to the back near the DC input plug. I highly recommend the use of some sort of power switching for the TV. Even when turned off, there is still standby power running in the TV that will draw from the battery over time. So it is handy to have some sort of power disconnect for the TV.

Don't know if this information is helpful to anyone but feel free to ask if you have questions.

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A quick note for Isabug. (or anyone) If you don't want to have to do any wiring with the fan and want to use a cigarettte lighter plug, there is this on Amazon for cheap. If you need longer there are extension cables. Do a search for 2.1mm cable. No fuss, no tools if you have the lighter plug already.

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I think I might have figured out why it has become so hard to find TV's with external power supplies. Energy Star ratings. Just a guess. The cheaper manufacturer's probably don't care about the rating so you will find some. The task however is arduous at best. Scouring the web and looking at the pictures to see if you can tell if there is a power brick or wall wart. If not take the top half dozen small tv's you might be interested in and search for the model number plus manual. The manual will have pictures of how to set it up, what is included and like the fan, will list the voltage at the DC input.

Here is a Element one I found at Amazon. Look at the pictures and you will note there is a power plug that says DC 12V. Don't know the size of the plug however but worst case you can cut the cable off the brick and splice it in if it is not 2.1mm. Walmart and I think Kmart sells this brand also. Back to my original suggestion. Hit up the big box stores and have a look at the backs for a 12V plug.

Here is a guy who posted this video on youtube just back in April from a set he got at Walmart.

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I would bet that the TV will run just fine on 12 volts. I have found that a lap top computer runs fine on 12 volts all though they have a 19 volt input the only thing it won't do is charge the battery with out the 19 volts in but the computer works . Granted a TV is not a computer but the TV supply has an input voltage that is rather broad with figures similar to a laptop power supply and I suspect the TV is capable of some pretty wide input voltage. Do not go and buy a TV because I said so! But I would bet $5 it will.

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I would bet that the TV will run just fine on 12 volts. I have found that a lap top computer runs fine on 12 volts all though they have a 19 volt input the only thing it won't do is charge the battery with out the 19 volts in but the computer works . Granted a TV is not a computer but the TV supply has an input voltage that is rather broad with figures similar to a laptop power supply and I suspect the TV is capable of some pretty wide input voltage. Do not go and buy a TV because I said so! But I would bet $5 it will.

Well if I was going to risk $5, I'd just go all in and get a 3 amp DC voltage converter for the extra dollar. $6 to ensure it is not under voltage is cheap insurance. The other point is that the conversion is really energy efficient as buck converters work on duty cycle with very small losses. And cheap to boot. Up voltage or down you can easily set them to the voltage you need.

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TV's are becoming increasingly harder to find with external power supplies like the one I installed in the RV. That said, the way you tell what the voltage and polarity of most devices is usually the really tiny label (I wish they'd stop that) on the power supply or often on the device itself at the DC input plug.

Lets start with the simple one, the fan. On the fan next to the plug it has a little label saying 12vdc, 500mA with a picture above that shows the outer portion of the plug ring as the - (minus or ground) and the inside center as + (positive). The plugs I bought at Amazon match and are also marked. Center is + and outside ring is -. In my case I ran some two conductor lamp cord. You can get that at home depot. It is very flexible and you'll notice there is one side that is ribbed. I use this side for the ground connection and the other the positive. The connections are held in place by the screw terminals. I wired it directly into the DC section of my power center along with a few other devices. In fact I ran the wiring to a few locations so that I could use the fan in the window near the sink, dinette (couch is there right now) and berth. I just plug in and turn the fan on. What I like about this particular fan is even on high speed, its current draw is only about a half an amp which is very little for the amount of air it moves. Hope this is making sense.

fan_02.jpg

Now the TV. This is more complicated because I had to find it first. I also installed it a couple years ago (yes I know, I'm just getting caught up now with sharing). I shop online quite a bit including a site called Woot. They often have various refurb items and I had been looking for a TV because the wife wanted it. One day they had several different sizes and when looking through the pictures, I noticed there was an external power supply on this one. Still, that meant nothing. I had to go to the Visio web site and download the manual. In the specification it listed the voltage as 12 volts and I was good to go. As I type this, I already feel like I'm not helping. If you want to do something similar, here is what I would suggest. Hit some of the big box stores like best buy or walmarts and look at the small TV's on display. See if any have an external power supply. Bring your reading glasses cause the labels are going to be small. Here is the one for the Visio. Notice just like the fan, it lists the output of the power supply as 12V (it should say DC but the solid line with the dashed line below indicate DC) and 4.58 A.

tv_power2.jpg

In the end, you might be stuck either buying a no-name just to get a DC powered TV or going the inverter route. My post was more about thinking in terms of the most power efficient way. It's the holiday tomorrow and I've family coming. We are having a camping get together in my back yard. Seems like the only way I'm going to be able to camp these days. If I have time next week, I'll do a bit of searching and will see what I can find. Who knows, maybe there is still something out there. As a refurb this Visio was really cheap. Perhaps some others might chime in with something that will work.

Quick addition and question. What size range?

Thanks again for the lengthy explaination @Back East Don. I read through your info. twice - will probably need to read again to fully understand it but at least now I know how to tell if the electronic is 12v, look at the back and the Output. I've always looked back there but it's been jargon to me until now.

And you used the lamp 2 conductor cable from the home depot to extend the 12v wiring so you could plug in your fan at multiple locations - using the ribbed part as the ground. That's cool - pun intended - and it seems pretty easy to do - except for the part about the DC section of your power center. Do you mean the box under (my) sofa with all the fuses? If so, do you just connect the cable to an unused fuse terminal? Is that how you add an extra 12v power outlet?

Thanks for the pictures, they are very helpful.

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A quick search found a series of LG TV's with external power supplies but there is a problem. They are 19 volt not 12 volt.

lg_tv.png

The solution is a buck converter. These are available on the web including Amazon and come in up convert and down convert. They are typically a small PC board with an input and output and are either programmable or have a simple adjustment mechanism. You just have to pick the appropriate one for converting higher or lower voltage and selecting one that has enough current output to drive the device.

You can find smaller current ones starting at less the $6. Here is one from Amazon that is about $16. It is rated for 6 amps and will take an input between 4.5 - 45 volts and output anywhere from 5 - 60 volts.

The buck converter looks like a piece of candy to me - that or a lego. This part is definitely going to take more brain power to understand.

Regarding size of tv, I'm thinking 19-22" or so. I was also thinking of one of those combo DVD units but that might be even harder to find as a regular tv. I will start looking at best buy now that I know what to look for.

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I think I might have figured out why it has become so hard to find TV's with external power supplies. Energy Star ratings. Just a guess. The cheaper manufacturer's probably don't care about the rating so you will find some. The task however is arduous at best. Scouring the web and looking at the pictures to see if you can tell if there is a power brick or wall wart. If not take the top half dozen small tv's you might be interested in and search for the model number plus manual. The manual will have pictures of how to set it up, what is included and like the fan, will list the voltage at the DC input.

Here is a Element one I found at Amazon. Look at the pictures and you will note there is a power plug that says DC 12V. Don't know the size of the plug however but worst case you can cut the cable off the brick and splice it in if it is not 2.1mm. Walmart and I think Kmart sells this brand also. Back to my original suggestion. Hit up the big box stores and have a look at the backs for a 12V plug.

Here is a guy who posted this video on youtube just back in April from a set he got at Walmart.

Nice, I will look at that one too. And splice it to that little terminal adapter.

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A quick note for Isabug. (or anyone) If you don't want to have to do any wiring with the fan and want to use a cigarettte lighter plug, there is this on Amazon for cheap. If you need longer there are extension cables. Do a search for 2.1mm cable. No fuss, no tools if you have the lighter plug already.

Awesome, thanks for the links!

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Awesome, thanks for the links!

Just make sure if you go with the O2 Cool fan that you select the 10" one that will take the power adapter. This one actually comes with the AC power adapter. The small 5" ones are battery only.

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Thanks again for the lengthy explaination @Back East Don. I read through your info. twice - will probably need to read again to fully understand it but at least now I know how to tell if the electronic is 12v, look at the back and the Output. I've always looked back there but it's been jargon to me until now.

And you used the lamp 2 conductor cable from the home depot to extend the 12v wiring so you could plug in your fan at multiple locations - using the ribbed part as the ground. That's cool - pun intended - and it seems pretty easy to do - except for the part about the DC section of your power center. Do you mean the box under (my) sofa with all the fuses? If so, do you just connect the cable to an unused fuse terminal? Is that how you add an extra 12v power outlet?

Thanks for the pictures, they are very helpful.

Sorry but yes I mean the box under the sofa (mine used to be under the dinette but I've made changes) Yes, you can connect it to an unused fuse terminal then plug in an appropriate fuse. If just the fan go with 5 or 10 amp as just a safety. If you add more then you will have to add it up but if you put too many things on one circuit a bit of care needs to be used to ensure the wiring is appropriate. For most of this electronic and fan stuff, this is not an issue. A 10 amp fuse would power about 20 of those fans. That is why I explained how to read the power input label. Then it is as easy as adding it up and giving it at least a 20% margin on the supply fuse. I get that not everyone understands electricity even though DC is the easiest in many ways. I did also post this in the DIY section but happy to help explain it.

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Sorry but yes I mean the box under the sofa (mine used to be under the dinette but I've made changes) Yes, you can connect it to an unused fuse terminal then plug in an appropriate fuse. If just the fan go with 5 or 10 amp as just a safety. If you add more then you will have to add it up but if you put too many things on one circuit a bit of care needs to be used to ensure the wiring is appropriate. For most of this electronic and fan stuff, this is not an issue. A 10 amp fuse would power about 20 of those fans. That is why I explained how to read the power input label. Then it is as easy as adding it up and giving it at least a 20% margin on the supply fuse. I get that not everyone understands electricity even though DC is the easiest in many ways. I did also post this in the DIY section but happy to help explain it.

Great, I will go and read that in DIY too. Many thanks again!

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Great, I will go and read that in DIY too. Many thanks again!

Sorry but I mean this forum section is Do-It-Yourself. It is sort of my way of justifying making your head hurt.

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The buck converter looks like a piece of candy to me - that or a lego. This part is definitely going to take more brain power to understand.

Regarding size of tv, I'm thinking 19-22" or so. I was also thinking of one of those combo DVD units but that might be even harder to find as a regular tv. I will start looking at best buy now that I know what to look for.

I'm a big fan of brain power.

Buck converters. One moving part plus a power source input and an output. Simple so far. Here is a picture of the little lego piece. I picked this one because it is simple in layout for explanation purposes. For an RV application, I would suggest spending a couple more bucks (I can do puns too) and getting one that has the same type of screw connectors that I used to connect the wire to the fan. This one the inputs are solder and we don't want to go there but good for explaining it all.

buck-convert_up.png

There are 4 wire connections on these. Voltage + in and - in that is for the battery side (power thing under the couch) and voltage + out and - out that goes to the connector that goes to the TV. So connecting it is the easy part. These come unadjusted to any particular voltage out. To the right of the In - you see a blue device labelled on the board as R1. This is a variable resistor and is what is used to set the output voltage. It is one of these multi-turn type so to get the voltage anywhere to near the right voltage (in the case of the LG 19V) you may have to turn it either clockwise or counter clockwise as much as several complete turns. This unfortunately requires some sort of volt meter. Not a bad tool to have. They do lots of useful things if you learn some of the basics (beyond this post). A meter will have two leads and a variety of functions. Here is a pretty simple Fluke meter.

meter.png

Alright, it looks daunting doesn't it but lets review a couple things. Remember when I explained on the Visio power supply that the solid line with the dash below indicated DC. This meter has 3 voltage test modes. Going from off there is a V with a little wave symbol. That is AC like your power at home. The next has the V with the familiar lines. That is DC. The 3rd is mV which stands for millivolts or hundredths of a volt. Seldom use that function at all.. Down at the bottom there are two inputs you cannot see but the labels are there. Com which in the case of DC is ground and the other which has the V followed by a bunch of silly looking symbols for the DC voltage input. A black lead will go to com and red to the other.

Now you might not have a meter. Understandable as it might not be a common tool for everyone. This one is also a bit spendy at $50 (lowest price). There are very cheap (like $10) meters on amazon. For the money though I think I would skip it and get one of these. It is a simple led DC volt meter that you can either permanently wire into your RV to let you know how much juice is left in your battery when running without AC or just use to adjust the buck converter and put it away somewhere in case you ever need it again to say perhaps, adjust a buck converter. Notice there is a red and black lead on it. By now I think you might be getting the idea on how to hook this up. Anyway.

Setting up the buck converter is a matter of plugging in the DC voltage input without anything connected to the output except the meter. With the meter's black lead connected to Out - and the red to Out + (meter is on in DC voltage mode) simply read the voltage and adjust the R1 resistor screw either clockwise or counter clockwise till the correct 19 volts is achieved. Remove the meter leads and connect the wire with the connector that will plug into the TV to the appropriate + and - and you are good to go. It is a good idea that while doing the connections both at the input and later at the output that you remove the fuse in you power center as a way to ensure there is no voltage there. At this level the voltage is of just about no risk to you but a misstep and subsequent short and you will let out the magic smoke the device run off of (inside geek joke)

I hope this at least makes some sense. I posted this mainly as an addition to further clarify how some things are accomplished. So thank you for your questions. I am hoping they help others out without having to ask themselves.

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At last, after speaking gobble gook to folks for a long time, someone who knows what a buck/boost is. Welcome to the wilderness.

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At last, after speaking gobble gook to folks for a long time, someone who knows what a buck/boost is. Welcome to the wilderness.

Fluent in gook with an understanding of the simple single inductor DC to DC converter chip circuit. Lots of flyback stuff in TV's, old camcorders and such. Wife hates the wilderness though, she likes the beach.

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TV's are becoming increasingly harder to find with external power supplies like the one I installed in the RV.

Many of the smaller then 32" Sceptre LCD-LED TVs run on 12 volts DC and come with separate power supplies clearly marked "12 volts DC." So does my new LG Blue Ray player. I used to think it was a great advantage for an RV. Not any more. I have one main inverter in my RV. Very little loss, no noise, and it runs any cheap appliance I want. Saves a lot of messing around. When we camp there is never any grid power available. I just take the main RV power cord and plug it into my inverter and then everything wired AC in my camper works. Obviously this would NOT work with AC but we never use AC in the RV or our house.

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Many of the smaller then 32" Sceptre LCD-LED TVs run on 12 volts DC and come with separate power supplies clearly marked "12 volts DC." So does my new LG Blue Ray player. I used to think it was a great advantage for an RV. Not any more. I have one main inverter in my RV. Very little loss, no noise, and it runs any cheap appliance I want. Saves a lot of messing around. When we camp there is never any grid power available. I just take the main RV power cord and plug it into my inverter and then everything wired AC in my camper works. Obviously this would NOT work with AC but we never use AC in the RV or our house.

Do you have a sine wave inverter or square? A lot more money for the sine wave ones but for any inductive loads you don't end up with the 20% more power usage like with a refrigeration compressor. The transformers in the typical wall wart won't care about a square wave AC but I've got a couple laptop supplies that don't like it at all. Gets hotter than hell. Would not want to run them that way on a regular basis. Some electronics are sensitive these days as power supplies are not over built like they used to be. This is the reason I abandoned the (cheap) inverter and just wired everything directly. Little to no conversion losses and no power supply overheating.

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How are the little buck/boost units with RF noise? I have several LED's with buck/boost regulators and they desence my FM radio some thing wicked even with some added caps! I am listening to a Sirius radio right now with a 12 volt rated input playing just fine with a 9 volt wall wort it 's the radio from the camper that was how I cured the RF noise in the camper FM radio!

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How are the little buck/boost units with RF noise? I have several LED's with buck/boost regulators and they desence my FM radio some thing wicked even with some added caps! I am listening to a Sirius radio right now with a 12 volt rated input playing just fine with a 9 volt wall wort it 's the radio from the camper that was how I cured the RF noise in the camper FM radio!

The osc in the chip is only 52kHz and even with ringing in that little inductor, I cannot see it creating RF issues in the FM band. Not following what you mean by "desensce" but if noise it is more likely through the power as lots of automotive radios have little filtering there.

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It wipes out the receiver no real noise just kills the receiver front end to the point it's all most like the antenna was unplugged. I don't know what the freq is the counter will not pick it up. It's mixing with some thing in the FM band and the IF but like I say the sat stuff is way out of it's range so I still have my tunes!

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Do you have a sine wave inverter or square?

I don't think so-called "square wave" inverters exist anymore. Modified wave inverters took their place and are cheap. You're not going to find any "true sine wave" inverters either at a portable consumer lever unless you spend a fortune. My house had two true sine-wave outback inverters to run a solar grid-tie setup but that's only because they are a requirement for grid-tie.

A 2000 watt (4000 watt surge) mod-wave inverter costs $130, more-or-less. A so-called "true sine-wave" inverter 2000/4000 watt (although it is NOT true sine-wave) will cost twice that or more. Square wave inverters are a thing of the past although mod-wave and sine-wave inverters have right-angle stepped waves instead of curved sine-waves.

As to compatibility? I've had just about zero issues with any of them - but it's a crap-shoot. My old Trace/Xantrex DR2412 is a mod-wave, 2000/4000 watt combo inverter/charger made for off-grid solar. NOT a cheap portable. Made for hard-wiring. It can run near anything except hard-wired smoke alarms or any GFCI outlets (makes them buzz). My portable Ramsond Sunray 1500/3000 "sine-wave" inverter runs GFCIs and smoke alarms fine but does not start compressor motors as well as my mod-wave Trace/Xantrex.

I've got over 30 inverters here and could go down the list of pros and cons. For the most part, even my $99 Harbor Freight 2000/4000 watt mod-wave inverter has been great and I've had zero compatiblity issues except with smoke alarms and GFCIs. Run many a power tool, air compressor, computer, and TV with it.

For an RV - for general use, microwave, refrigerator, TVs, computers, etc. - it's hard to beat a cheap mod-wave inverter UNLESS it has a full time cooling fan that some cheap ones have. The fan noise drives me nuts inside an RV. The better ones have thermal activated fans that never come on in general use. All inverters wipe out AM radio reception which is one draw-back. Mine (in my RV) has a remote control and if driving and trying to listen to AM, I turn it off.

The only "bad" inverters I've ever had were from Vector/Black & Decker and a few Chinese no-names. Bad advertising is also an issue. Some sellers advertise by the momentary "surge" rating instead of the true usable power - kind of like what Honda does when they sell their 1600 watt generator as a "2000."

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The transformers in the typical wall wart won't care about a square wave AC but I've got a couple laptop supplies that don't like it at all. Gets hotter than hell.

Many older laptop power supplies as well as many battery chargers do NOT work well with many inverters (mod-wave and sine-wave) as well as not working well with many portable AC generators. Been a well know fact and problem for many years. It's still kind of a crap-shoot. I've got six lap-top computers and never had any issues with any of the power supplies working from an inverter. In fact. we have a portable Duracell 600 portable power-pack with a 26AH battery and a 600 watt mod-wave inverter. We've used it for years on lap-top. My wife is homeschooling our last child and when I'm in the woods cutting - she, the boy, and dog come along and use the laptop in the woods for school programs. That little 600 watt inverter and power-pack has worked flawlessly with all our HP, Sony, and Dell laptops. We've thrown it into our van a few times too to watch movies on a 32" TV and DVD player with no issues. Great little portable AC power source. Also the best DC 12 volt jump starter I've ever used.

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I don't think so-called "square wave" inverters exist anymore. Modified wave inverters took their place and are cheap. You're not going to find any "true sine wave" inverters either at a portable consumer lever unless you spend a fortune. My house had two true sine-wave outback inverters to run a solar grid-tie setup but that's only because they are a requirement for grid-tie.

You are the guy to talk to about inverters. My personal experience goes back a ways and is obviously out of date. Some of the high end recording studios I am familiar with ran off of a room full of batteries and very large refrigerator size inverters. They certainly spared no expense.

As to clean sine waves there is also the option of a Walsh Transform Generator where you drive 3 harmonically related square waves into independent windings of a transformer and the core sums them delivering a sine wave. Way too complicated for an RV.

A number of years back the company I work for bought us inverters for our vehicles so that we could keep our computers charged up while in the field. They were not the cheapest or most expensive but they certainly didn't like either my Lenovo or Dell power supply. Ended up buying a Targus AC/DC computer power supply. When I got this RV about 5 years ago I got a cheap-ish inverter and was still having mixed results with some supplies so I abandoned it for just connecting to DC.

You've given me lots of good info. I think perhaps I am worrying too much about efficiency as well. For some reason I have it in my mind that until you begin to reach a higher percentage of rated output with an inverter that there can be some significant losses. I don't have the issue of running high current loads but I only have one battery and my minimum is 4 days on the charge. I keep adding to the sum with more gear but I'm thinking I still should be good. Heading out Wed on a trip so it will be interesting to see with new batteriy and the addition of 3 fan vents how we do in mid 80's temperature with everything else going.

To clarify, this RV is just the training environment for the next one. While my interest in this subject is not directly related to how I use this one, life changes are in the works and how we use an RV will change as well. I tend to go overboard with my incessant planning.

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It wipes out the receiver no real noise just kills the receiver front end to the point it's all most like the antenna was unplugged. I don't know what the freq is the counter will not pick it up. It's mixing with some thing in the FM band and the IF but like I say the sat stuff is way out of it's range so I still have my tunes!

I'm 20 years removed from radio work but this doesn't sound like RF. Ground issue maybe but otherwise stumped. If you mean the cab radio, there are two electrical systems in the RV with the radio fed by one and if I am understanding you lighting is house side, that is on another. The grounds are common but that doesn't mean they aren't an issue and ground loops can do strange things. AM good? Ant ground? I repaired car radios but dislike them. Hateful little devices.

Edit: This kind of question is the stuff that keeps me laying awake at night. (I kid). A quick (or not so) rational. It's a cheap power supply for a led light. What range do you think it operates in? It is not going to be high freq as they wouldn't want the added cost for components rated for it or the added complexity. FM is 66 to 108 MHz. and even IF is 10.7. Even if I was willing to calculate out complimentary frequencies, I just can't see some light putting out enough broadband RF as to kill the entire FM band. Make sense? Every station? Some strange ground related noise..maybe..who knows...kinda sounds like a crap shoot. I don't know what you've got installed, how it is installed and how tight your DC electrical system is. Maybe you popped the radio in the dash and are counting on a iffy antenna ground and didn't bond the black ground wire at all. Maybe you did and even used the little metal strap that came with the radio to secure it and it is in better than I could have done. Still a bunch of unknowns but still not sure why you are convinced it is RF or IF. You said you tried caps. On the power? Try a little bit of L with the C. Makes a better noise filter. They used to make LC filters in little cans for Alternator whine. I've no idea what to suggest for EMI, RFI or what ever kind of noise this led light power supply of indeterminate design and manufacture is crapping out.

I am publicly on record in this post as stating I dislike radio. Radio is dead to me (and a dying platform for many). This is just one more reason added to my list.

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I bought a Sceptre 19 inch TV with dvd player from Walmart 1 year ago for $89 on sale. It runs on 12 volt, not the best sound but ok picture. You can cut the ends off of a extension cord for electric cable.

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I am publicly on record in this post as stating I dislike radio. Radio is dead to me (and a dying platform for many). This is just one more reason added to my list.

I'm on record as loving radio. Especially AM. I guess the experience is not quite what it was in the 30s with no TV or computers, and the family huddled around the big Atwater-Kent, listening to "fireside chats" from the president. "Talk radio" with the president began in the late 20s on WGY on the AM band and WGY is still going strong. Today, wherever I go, I can always get something on AM and I find that fascinating. Especially in the evening during the ionospheric bounce. It still works where cell-phones and Wi-Fi setups do not. FM, AKA "the Armstrong System? Good for music but with a much more limited range. I've never found it "interesting"; just OK to listen to when it comes in. I DO find the Armstrong family lawsuit interesting. I did old man Armstrong in when FM got virtually stolen from him, but his family prevailed in the courtroom after his death. Armstrong and FM radio, along with Henry Ford against the U.A.W. represent a fascinating part of corporate history when virtually one man stood up to the bullies.

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I'm on record as loving radio. Especially AM. I guess the experience is not quite what it was in the 30s with no TV or computers, and the family huddled around the big Atwater-Kent, listening to "fireside chats" from the president. "Talk radio" with the president began in the late 20s on WGY on the AM band and WGY is still going strong. Today, wherever I go, I can always get something on AM and I find that fascinating. Especially in the evening during the ionospheric bounce. It still works where cell-phones and Wi-Fi setups do not. FM, AKA "the Armstrong System? Good for music but with a much more limited range. I've never found it "interesting"; just OK to listen to when it comes in. I DO find the Armstrong family lawsuit interesting. I did old man Armstrong in when FM got virtually stolen from him, but his family prevailed in the courtroom after his death. Armstrong and FM radio, along with Henry Ford against the U.A.W. represent a fascinating part of corporate history when virtually one man stood up to the bullies.

I am hoping that it is understood that the statement is tongue and cheek. Radio is fine but I think only alive because it comes with the car you buy. Not something stand alone that people are running out in droves to purchase these days. When traveling, I'll sometimes tune into local radio especially back when the rentals didn't all have a aux input. Sometimes I want the local flavor. For the everyday though I am into narrow casting (podcasts) You can pick your subject or interest and stream or download it to your phone or tablet and listen in on your schedule. You are also not listening to a half hour of banter and ads for every hour of content. Some podcasts are ad supported but it is done sparingly. Audio books get added to the mix when flying a lot. Good to be able to shut my eyes and kill hours on a long flight.

Getting in and out of Boston regularly can mean over 4 hours a day of driving for me. Morning zoo radio talking about what some celeb did drives me up a wall. AM talk is typically political and I'm trying to cut down on my outrage. (I have a doctors note if you need it) I'll tune into AM at some point as I approach the city for traffic so I can figure out alt routes.

I am a good natured guy in life and on the internet but if you find yourself asking "is this guy serious?" when reading anything of mine, figure on the answer as being no. I try to preface what I post as things like, what I understand or have read and such. I'm one of those who loves to learn and is well aware that what I know with any absolutes is very small. I have broad awareness on many topics and very narrow band of things I can claim expertise status.

Thanks for all the input. I always find the information posted very interesting and useful.

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