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It sounds like this might be fairly easy, but I am a little fuzzy on the details. Per Jaak's suggestion, it would seem that you could just intercept the audio line from the sat receiver with a switch of some sort. Then, the SAT receiver opens the line into the radio, and then it is just a matter of hooking your own audio in. If somebody could just fill me in on some of the details, this might be a project for next weekend!
 

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With the PAC adapter in the way, how will you control the SAT radio on the deck? Even if you could intercept audio from the receiver in the trunk, there would be no way to change channels.
 

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I'm talking about leaving the PAC adapter out all together. Basically, the radio thinks that I am playing SAT, SAT info would show on the display, but an outside audio source of my choosing would play through the head and speakers.
 

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You need a unbalanced e.g. RCA jacks input to balanced output, converter that will take your audio/ground connection and convert it to audio+/audio- connections, and run this through relays or a switch, to change sources.

The following diagram shows the harness connections, but the colours are wrong, because this is for a USA-SPEC harness, not the Nissan OEM one. Wiring is identical except for one ground connection Nissan added. (Non critical connection, and potential ground loop, I might add.)
 

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The first one looks like it may work, the second one, the link is not functional right now, so I'll have to look again later.

I'm going to try something to see if I can make the Pac converter run as a second device, this weekend, I hope.

But there's one pin on the Sat the makes switches the audio input.

There's also a completely different harness set that that I now have and am going to try, that carries more wires than the ones I've seen before.

I'll look for a converter in the meantime...
 

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A quick search and what I've mostly found are expensive commercial level converters.

There is another couple of approaches that can be tried, are less than optimal, make me cringe when I think about proper hi fidelity practices, but may be "good enough".

They're cheap, so no harm done in trying them.

The first... Buy a couple of these:


From here, or your local store...

http://www.radioshack.com/product.asp?catalog_name=CTLG&category_name=CTLG_011_002_016_000&product_id=273-1380

Connect the 8 ohm secondary to the audio inputs on your audio device and the primary to the audio inputs on the extra sat connector. You can go from the centre tap to one side, if the audio level is too high. You need one for each channel (2).

Downside of this? Frequency response may not be what you hope for, depending on how good or bad these are, and how picky you are.

Bad practice number two, but still works:

Create a voltage divider out of the input by driving the unbalanced audio into the balanced audio inputs.

Get a couple of 330 ohm resistors and put the audio ground on one side and the audio signal on the other. (In other words, instead of connecting them directly, connect them through two resistors on each channel.)

This works for all the wrong reasons. It's not the right way to make the conversion, but the voltage drop accross the input creates a difference in the signal levels, and fools the input into believing a differential signal exists. Unfortunately, it gets hit with a higher signal level than is necessary, to get the desired volume level.

Positive: Better frequency response.

Negative: Greater chance of distortion, not as good isolation as the transformer.

Of course the best way is a proper converter. I'm hoping to get the pac audio unit working with my Sat this weekend, and have it all selectable through the radio. My chances? 50/50...

I'll have to look up the pin numbers for you...
 

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Oh, and you can use the SAT receiver to do the audio switching...

I'll have to put together the detail on this, but you can extract it from the project thread, if you're technical.
 

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Thanks Jaak for all the great info!! But like yourself I would like to do it the right way and only once , I have time with this and I am hoping your solution works as I am very interested.
 

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Well, first thing is to find a cost-effective converter... I'm sure it exists, just have to source one.
 

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That's the idea, but you need stereo and that's only mono. The other problem is the Phone style jacks are not the best from a reliability and noise standpoint and the XLR connector on the other side, while rugged, is not cheap either.

Hmm... I should go have a peek on Crutchfield again. This morning when I tried it, they were down being serviced.
 

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im thinking the one posted above in the extron link seems to qualify for the job, I just need to get pricing which I cant find anywhere I will have to call them directly, Hopefully it's cheap enough and no xlr's are a plus and it even runs on 12V
 

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Had another look at the specs and it looks perfect, if the price is right...
 

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I hope to have the pac audio unit running with the sat, next weekend, if the gods are smiling on me. But it means taking apart the radio to install parts.

To do it this way, one of the pins on the sat connector needs to have a wire run with +12 volts to switch the audio relays, and then an adapter, such as the one above, connected on the audio inputs on the "unused" connector.

There might be a simple way to do this... Hmmm....
 

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Hey Jaak I found out yesterday the msrp of the extron unit is 150.00 a bit too pricey , Ill keep searching for a cheaper alternative until then :confused:
 

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Jaak upon looking into the pac more , Would it be easier to convert the balanced sat inputs to unbalanced signals then input it into the pac unit leaving the other unbalanced input free for another accessory input? At that point the switching would be done by the pac unit thru the radio button . Let me know what you think
 

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No, 'cause the pac unit and the sat would collide on the data bus and if the pac unit doesn't get data, you can't control it...

You could build a converter, if you feel like soldering. This really is annoying.... The circuit cost isn't high, but it looks like everyone's trying to make a lot of money off this!

I've put one together, but I've not yet tested it. I'll post it once I have.

Got most of my parts in for the weekend experiment. It'll kick, if I can make both work together!

I could build something else that would work, that would be "plug and play" but I'm not about to buy 1,000 of each connector, to experiment. Ideally, I'd need three connectors, one for the sat harness to go into, another for the sat and the last for the sat output to the second device.

Easier for most people than soldering surface mount components into their radio guts... (Anyone want to go into production? Maybe I'll just post the how, and someone like Pac might make the product...)
 

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Well I actually spoke with pac yesterday and was asking if they had considered making this, They said it is somthing they were looking into but not in the near future , If there was more interest for it they may speed up design and production . As far as the connectors go I will try doing some research on who makes them (OE or aftermarket), I know you were talking to Generator about this , give me any info you have so far on them. Also what was the price on the connectors ? As a group effort we can reduce the cost by splitting up the investment .
 
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