Did the Converter Fry my Radio?

[kentuvman]

Greetings fellow A/S enthusiasts:

I have a 1976 21' Globetrotter. When I refurbished the interior, I installed a JVC digital am/fm cd player with a removeable face. It worked good for a couple years but last year it lit up like a xmas tree. I sent it to JVC and they repaired it. It worked for about two hours and died again.

I went to Best Buy last night and for $100 bought another one and this time with a 4 year replacement warranty.

I notice when I turn on the overhead lights this action interrupts the music.

Before I re-install is there something about the converter that is being hard on my stereo? What's strange is there's a 20amp fuse on the back of the radio but it never once has blown.

Thanks much,

Ken Tuvman

[RickDavis]

I assume you do have a battery in the trailer and it is good. not just running off the converter?
I would check the DC voltage with an accurate meter. should be in the area of 14 volts plus or minus a few tenths. If it is above 15 you are definitely having a converter problem.

[Minno]

Hi Ken,

Some random thoughts in no particular order...

Have you or a PO rewired the trailer? Is the radio on the same 12 volt circuit as the lights? When you turn on the overhead lights, do the lights on the radio flicker or go out completely, or even worse, get really bright? Might need to check that at night in a dark trailer if you can. Are you running the original converter, or has that been replaced?

Regarding the JVC - just because the factory repaired what they found wrong, doesn't necessarily mean they fixed the cause of the problem. Electronics can be finicky beasties sometimes, and one bad circuit or component can cause another one to fail. So, the logical thing is to replace the flailed component, do a go/no-go test, and if it passes, send it back to the owner or put it back into stock. But, the cause of the failure is still in there, so it's going to fail again. Power supplies are notorious for causing all sorts of problems like that. Harder than heck to troubleshoot - believe me. Can be worse that an intermittent problem in your car that decides to stop acting up as soon as you bring it into the service center.

In addition to checking the battery and voltage as Rick suggested, I would put the meter on the 12 volt power input to the radio, and watch it very carefully while you flip the overhead lights on and off. If you have a digital meter, changes while you flip the switch will be easier to see. If your meter has an ammeter function, try measuring the current on the radio power lead as well, again while flipping the overhead lights on and off. If you see spikes or changes while flipping the lights on and off, then I would try and wire the radio into another 12 volt circuit, if you can find one by the radio.

Good luck!
Chris

[kentuvman]

Hi Chris - thanks for your note - I'll answer your questions below:

Have you or a PO rewired the trailer? Is the radio on the same 12 volt circuit as the lights? When you turn on the overhead lights, do the lights on the radio flicker or go out completely, or even worse, get really bright? Might need to check that at night in a dark trailer if you can. Are you running the original converter, or has that been replaced? I removed the original radio; all I did was attach the harness - no re-wiring of unit as far as I know. The only thing that happened was when I turned on the overhead light, the sound cut out but then came back on.

Regarding the JVC - just because the factory repaired what they found wrong, doesn't necessarily mean they fixed the cause of the problem. Electronics can be finicky beasties sometimes, and one bad circuit or component can cause another one to fail. Was thinking about how I'm now on my 3rd or 4th Ipod because they also will fail over time.

So, the logical thing is to replace the flailed component, do a go/no-go test, and if it passes, send it back to the owner or put it back into stock. But, the cause of the failure is still in there, so it's going to fail again. Power supplies are notorious for causing all sorts of problems like that. Harder than heck to troubleshoot - believe me. Can be worse that an intermittent problem in your car that decides to stop acting up as soon as you bring it into the service center. Will check with my Voltmeter first and then if seems okay will install new unit. I just put a brand new battery in the trailer.

In addition to checking the battery and voltage as Rick suggested, I would put the meter on the 12 volt power input to the radio, and watch it very carefully while you flip the overhead lights on and off. If you have a digital meter, changes while you flip the switch will be easier to see. If your meter has an ammeter function, try measuring the current on the radio power lead as well, again while flipping the overhead lights on and off. If you see spikes or changes while flipping the lights on and off, then I would try and wire the radio into another 12 volt circuit, if you can find one by the radio. Sounds like a plan - thanks - btw - what part of the state is Lexington, MN?

[kentuvman]

Checked voltage - with and without power - voltage reading higher with power but only a few tenths - nothing major.

But radio was not working properly until I unplugged the power. Now it's okay on 12V. Wondering what could be going on? Maybe the converter isn't delivering consistent voltage? Everything else works okay - TV, lights, ice box.

Hummmm?

P.S. Had an idea - went to the Power Outlet and I was using the 30W outlet. I put on the 20W adapter and now the Ipod is playing through the speakers. Maybe I had too much juice running into my converter? I'm not saying I solved the issue but it's a good start.

[kentuvman]

I did not solve the problem. It works fine on 12V and the converter is sending in too much current. All other electrical works okay.

Am thinking of running a dedicated 12v wire from the battery to the power lead for the radio and calling it a day.

[68 Overlander]

My first AS was a 76 Sov and the radio was the first thing to go that got me thinking about things.

[kentuvman]

Hi Randy,

What do you think is going on? Why is the power destroying the radio? Is it because it's a JVC? What I don't understand is I put a 20 amp fuse on the power supply and there's a fuse in the back of the unit. The power difference with it on shore power is doing some damage but I don't get it.

All other aspects of power work - heat, lights, tv, dvd player, electrical outlets.

My best solution is to run a dedicated 12v line from the battery and bypass the electrical system built into the G/T.

Make sense?

[ventport]

Since you said that the power converter is putting out too much current, it's time to replace the converter. It may also wreck your battery over time or at least shorten it's life. Going direct from the battery to the radio should not make much difference since the power converter is also connected to the battery to charge it. Good luck Brian

[Minno]

Hi Ken,

Lexington is a northern suburb of the Twin Cities - between Blaine and Circle Pines.

The radio isn't failing because it's a JVC. It's because it relies on 12 volt DC power. And it wants fairly clean 12 volt power. The other electronic items you've mentioned (tv, dvd player) and the electrical outlets are all 110 VAC. They all run off of shore power, same as the converter. Not sure where you plug the ipod into though - is it also a power supply that plugs into a 110 volt outlet?

Anyway, if the converter is going bad, then it can wreak havoc with all 12 volt electronics in the trailer. This can include the radio, the circuit board in the furnace, and the circuit boards in the water heater and fridge if they have one. Plus, as Brian mentioned, the battery itself.

If you have the original, or close to original furnace, then the furnace circuit board may be heavy duty enough to put up with flaky 12 volt power for awhile.

On the water heater, do you have a button inside the trailer you push to light it, or do you go outside and light the pilot light manually? If you have a button, then there's a circuit board. If you manually light the pilot light, then there is not one.

With the fridge, do you push a button on a control panel to turn it on? If yes, then you have a circuit board in it as well. The old style, where you hold down a gas button while pushing a clicker button to light the pilot light do not have circuit boards.

The 12 volt lights won't care if the power is flaky. Light bulbs are not particularly sensitive to minor voltage and amperage changes. That would be different if you have LED lights. They have circuit boards.

The fuses on the input to the JVC will protect it from power surges. They will not protect it from voltage spikes. Fuses don't care about voltage too much, only amperage. You could invest in a really good 12 volt filter to clean up the 12 volt supply to the radio, but I think a new converter would be cheaper. If its the original from 1976, and it's acting up, it's probably time to replace it. Especially if you plan on running other 12 volt electronic items.

Chris

[kentuvman]

Thanks Chris,

Your msg. makes sense. The other item that is on the fritz is the control panel. for the aux. water pump - I removed it last season when I replaced the "ceiling" above the sink and under the overhead storage unit. It was working okay and I notice now it's completely dead except for the exhaust fan.

How easy or difficult is it for me to replace the converter and where are a couple good places to get them - is there a specific model I should look for?

You really nailed it for me. The radio did work for the first season but died the second. When I first got the unit, the converter made a pretty loud humming noise. Now it hardly hums at all.

Thanks everyone - you've really helped me understand what's going on.

[kentuvman]

I'd also like to know where I get a converter that is a pretty straightforward install.

[richinny]

BestConverter - Converters, Inverters, Electrical Supplies, Electronics (randy above) can fix you up with parts and great service and advice. he has already helped out two sob owner friends of mine :-)

[kentuvman]

Thanks everyone for lending support to my power problem inside my Airstream. And thank you Randy for taking the time to tell me what I needed.

I'm pretty mechanical but advanced electrical is not one of my forte's. In the end, I called a mobile mechanic recommended by the manager at Lakeview RV Resort in Houston. His name is Rusty Clark and used to work for Bob Jones RV who has high marks from this forum.

Rusty came out and did some tests and he brought a new converter along. He looked at my converter and said "Man, this is a dinosaur." I wasn't sure if he was referring to my '76 Globetrotter or the converter. He performed some tests and it was concluded my converter had reached the end of its life.

Rusty installed a new Intellipower unit and cleaned up the wiring harness that was a mess. There was a black wire running through the rear of the trailer that a PO had installed to run a chopper that mashes up stuff coming from the black water tank. We pulled the wire and got rid of it.

My control unit and water pump was inop so I had him look at that. It turned out the control unit plug wasn't fastened all the way and I'd somehow reversed the wires on the aux. water pump.

In two hours or so, life is good. I installed the new JVC radio and its working great! The new converter is smaller and hum-less.

Had I been closer to home in MN I might have tackled this myself but in the end it really made better sense to let Rusty do what he does best and let me pay from the money I earn doing what I do best.

Thank Y'all very much!