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Author Topic: TV/Radio Switch Function  (Read 3312 times)

tennsmith

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  • "Of the things I've lost, I miss my mind the most"
TV/Radio Switch Function
« on: March 29, 2010, 11:39:23 AM »
I've got a DHS Mobile Theater System in my coach.  Found the amplifier the other day behind a kick panel at the driver's left foot and it appears to have 2 wired inputs, one labelled mono TV and a second "plug" which I imagine comes from the dash radio and perhaps CD player.  Now, up in the overhead close to the video switching unit, there is a switch labeled TV and Radio and moving the switch from one position to the other is supposed to cause the DHS sound system to switch to the appropriate input.  The switch appears, to me, to be a single pole single throw ON/OFF type of switch and one side of it appears to be wired to + 12vdc.  Does this switch trigger some "relay" inside the DHS box to switch input from TV to radio?  The switch simply can not be a "signal routing" switch, it doesn't have enough wires going to it.

I'm having a problem getting a new TV to work with the older DHS system.  It works fine on radio, but when I switch to TV, I can hardly hear anything.  Wide open volume on the TV and I can hear a very soft TV sound, almost as if it is being "coupled" by wires in proximity as opposed to a direct connection.  It may be that the newer TV has a left/right (stereo) output female receptacle whereas the coach male plug appears to be a mono plug with only 2 segments.  Anyone out there have any suggestions as to how to troubleshoot/fix this problem?  Last question....does anyone have any  information on the DHS system or an owner's manual?

Thanks
Bob Smith
Huntsville, AL
2000 Itasca Horizon 36LD
300 Cat
6 speed Allison

Just Lou

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Re: TV/Radio Switch Function
« Reply #1 on: March 29, 2010, 02:25:31 PM »
Bob, this problem has been kicked around on some older threads here that I can't seem to find right now.

I think the problem you are having is that the output from your TV (not sure if you are using fixed output or variable) is not strong enough to feed the DHS.  I believe that in the original configuration, the radio provided a signal that had been through a pre-amp, with associated volume controls, and the DHS was just the final amp.  If your TV has another audio output (fixed v/s variable) you might try using that.

The final complaint that I have heard was that you lose your volume control (via the TV remote) if you have to use the fixed output. I can't remember any final conclusions being made.

Try searching over on the Winni-only board.

Try this link for additional info.  It may help lead you to some technical assistance.

Good luck...
« Last Edit: March 29, 2010, 02:36:01 PM by aka Porky »
'97 Bounder 34V (F53 w/tag), '99 Honda Accord EX

tennsmith

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  • "Of the things I've lost, I miss my mind the most"
Re: TV/Radio Switch Function
« Reply #2 on: March 29, 2010, 04:19:32 PM »
Thanks Lou, I  had found the DHS article already and it helped some, but didn't answer all my questions.  I'm pretty sure that my TV has a headphone only type of jack whose volume can be controlled with the TV remote, but it is likely an "unamplified" signal, incapable of driving the DHS system.  That's what I tried at first and could barely hear the output.  The DHS amp also has a left and right "speaker level" input, but I think the TV has only a single speaker and not twins, although I may be wrong.  In any event, that'll require more wires from the TV to the DHS amp and I'm not sure it is worth it.  Also thought about a small 12v stereo amp to put some "guts" into the TV signal to drive the DHS, but that TV input is mono, so I need an amplifier/mixer arrangement to take L and R channels and mix them, then amplify.

I'll also do some searching on the RV forum for older posts.  Personally, I'm not as pleased with the new search software as I was with the old.
Bob Smith
Huntsville, AL
2000 Itasca Horizon 36LD
300 Cat
6 speed Allison

Just Lou

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Re: TV/Radio Switch Function
« Reply #3 on: March 29, 2010, 04:34:28 PM »
Bob, my old Bounder didn't come equipped with any sort of surround system so I installed an inexpensive Phillips 5.1 system myself.

Selecting where to mount the small speaker boxes and running (and hiding) the wires was the only difficult part.  I like the result better than trying to integrate it into the radio speaker wiring.  I can now use the system for TV sound as well as CD/mp3/ipod and integrated AM/FM tuners.

May be that paralleling the DHS system will be the easiest for you.
'97 Bounder 34V (F53 w/tag), '99 Honda Accord EX

lost-n-ohio

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Re: TV/Radio Switch Function
« Reply #4 on: March 30, 2010, 07:49:21 PM »
Bob,
I don't have surround sound in my '98 Vectra but I too have the radio/tv switch.  On my Vectra, the switch provides power to a small, I think 40 dB, amplifier that gets it input from the TV.  I've replaced my TV and the output from the headphone plug does not provide enough volume to my speakers if there is much background noise.  I'm planning on replacing the existing amp as soon as I can find one with more gain.

There are relays someplace that switch the speakers.  You can go to Winebago's website and download the electrical diagrams for your coach.  They might help you figure out how your system is wired and how it is supposed to work.

tennsmith

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  • "Of the things I've lost, I miss my mind the most"
Re: TV/Radio Switch Function
« Reply #5 on: March 30, 2010, 07:55:48 PM »
Interesting...my TV/Radio switch does appear to be a 12vdc "switched" voltage to something...mebbe I have one of those little amps somewhere also...but if I do, I think it may be kaput.  I'll look some more tomorrow when the sun is up.

Bob Smith
Huntsville, AL
2000 Itasca Horizon 36LD
300 Cat
6 speed Allison