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Son of a gun...


I never thought of doing it this way.

Not a bad solution you have, however a few modifications and caveats...


1) I assume that you'll still need some sort of cassette in the drive to keep the tape player working and switched on.

A modified cassette or even an old adapter cassette would do fine for this!

2) There is no need to completely disable the tape player, merely wire in a DPDT switch.

In one position, the tape player plays normally. In the other it gets input from your new AUX in.

You merely need to use good shielded wire, with the outer sheath grounded so as not to pick up noise.


I like the elegance of this. No major surgery required, and less possibilities of errors with the desoldering.


I need to find out exactly where you are patching in....


I'll report back once I've consulted the schematics (yes Virginia they ARE available on the net... gota love those Russian sites...)


Great job!
 

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opjose said:
Son of a gun...


I never thought of doing it this way.

Not a bad solution you have, however a few modifications and caveats...


1) I assume that you'll still need some sort of cassette in the drive to keep the tape player working and switched on.

A modified cassette or even an old adapter cassette would do fine for this!

2) There is no need to completely disable the tape player, merely wire in a DPDT switch.

In one position, the tape player plays normally. In the other it gets input from your new AUX in.

You merely need to use good shielded wire, with the outer sheath grounded so as not to pick up noise.


I like the elegance of this. No major surgery required, and less possibilities of errors with the desoldering.


I need to find out exactly where you are patching in....


I'll report back once I've consulted the schematics (yes Virginia they ARE available on the net... gota love those Russian sites...)


Great job!
if i sent you a radio would you do the mod? of course i would pay what you charge.

lmk this is a long ways off but just something to throw out their
 

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opjose I'll drive to DC as well and pay you also, I just think that is way too scary for me to do. I would end up frying the darn thing then I would be s*%t out of luck!!! Let me know..........
 

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Uh... You really might as well just use a tape adapter by the sounds of things... I wouldn't wanna screw w/ my tape deck lol I use that thing...
 

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My $02 worth....


This solution is brilliant for many reasons, but in needs some additional minor changes.

What this modification does:
----------------------------------------

The modification intercepts the signal going from the Tape deck unit, to the audio pre-amplifier. With a switch and jack (or wire as Dangie posted, though see below for a better alternative...) the audio from your MP3 player is routed to the pre-amplifier directly, as if the MP3 player were the tape deck unit itself.


Why this is good;
______________

Much better S/N ratio than anything else.
No induced noise from outside sources.
No low end roll off and a tad better high end response.
If done properly, it looks much cleaner.
Ability to hide all wiring.
Coolness factor.

Why you might not want to do it.
___________________________

Extra work.
Cassette adapters give good results which are ALMOST comparable.
You can screw up your stereo if you don't know what you are doing.
Voids warrantee on stereo.


Why this solution is "brilliant".
-------------------------------------------
The tape pre-amp input, expects 388mv PtP current... guess what MP3 players put out? Yup, same thing!

No additional circuitry is needed.
Reversible (see modifications to Dangie's design below).
Does not impact normal function (see modifications to Dangie's design below).
If you screw up, you may only be affecting the tape deck which can be swapped out with a pulled (cheap junkyard) unit WITHOUT requiring a Tech II remarrying!

Drawbacks:
-----------------
Tape unit must be running (engaged) to hear MP3 player.

The best way to engage the tape unit is to use a cassette adapter and cut off the provided cord. This will keep the capstan spinning and the tape unit active, but will not actually run tape past the head, so the only wear and tear is to the capstan impeller.


Modifications to Dangie's design:
------------------------------------------------

Dangie's idea is brilliant, and I assume that he and Michael worked without schematics.

A set of schematics would have revealed that you DO NOT have to cut the traces!

Refer to the picture with the words "Very carefully (!!) make a cut with...." under the picture...

Notice the two horizontal surface mount resistors immediately above the cut he made.
Those are 0 ohm resistors. That means that all they do is jumper or bridge the circuit between them.


If you remove the resistors, you could just as easily substitute a wire in their place and things would be no different.


Get the picture?

Instead you can remove the resistors and take the lower side (closest to the cut) to the CENTER poles of a DPDT switch, and the upper side (closest to the black IC chip just above them) to ONE SIDE of the DPDT switch. When the switch is turned to bridge the connection, the cassette/tape deck works normally.

The other side of the DPDT switch, gets it's input from your MP3 player. This can be done via an input jack (as I am going to do) instead of Dangie's hardwired plug.

I would also suggest a quick release plug so that some unknowledgeable shop tech, doesn't accidentally rip out your handiwork, in trying to remove the Stereo Head unit.



No CUTS required!

The beauty of this is you can always later place a wire in place of the resistors, or restore the resistors and the radio will be as before.


Also since all modifications have been done to the tape "module", which is easily removable, you can always swap in another one.

The item which is married to your car, is the much larger motherboard (circuit board) which remains unmodified.

You can swap CD player modules and Tape deck modules without having to worry about needing a Tech II.


So there you have it, the first fully viable MP3 AUX in solution for the 9-5's.



 

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Except the same problem stands... you have to put a tape in the tape deck anyway to make it work. If there was a way to do this w/o having to activate the tape deck I'd be all for it. Maybe there is a way to switch a detection circuit or something? Also... If you don't have a CD changer, is there a way you can tap into that connection or something? I just don't see a reason to modify anything if you end up shoving a tape in the tape deck anyway. Just get an adapter for like 10 dollars and save your self time and the possibility of destorying your stereo.
 

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Hey, If you don't want to do it, merely don't do it.

Don't come in and poo-poo the effort.


I've listed the reasons why someone might not want to do it as well as the reasons for doing it.

Usually the people who are interested in this do so for very specific reasons.

I wouldn't assume that because you are disinterested, that others may not be.

There are quite a number of threads devoted to AUX in's etc. so obviously the interest -IS- there....


To answer your post;

No there is no way to get around the need to shove a dummy cassette in. The mechanism uses several checks including optical sensors.

No the CD changer uses the Ibus so there is no way to tap in, as anything connected must be able to communicate via the iBus to activate the head unit's input.


A 10 dollar adapter works, but if your looking at this thread, it is probably not what you want anyway.
 

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since you seem to be the pioneer in these adapters ill direct my questions to you.

do all 9-5 come with the Tel-Mute? or is that only in the Harmon Kardon?

Cause i saw on another thread they use the input from that. Why not use that instead of the tape one?

Also would u do this for money? If i paid for shipping both ways, i bet it wont even take you an hour of time now that u know what ur doing. Figure most car install places get 50-100 an hour, and you could make a little spare money if your not to busy. This is a ways off tho, but let me know :)
 

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Re: Tel-mute

Yes they all come with the Telephone muting circuit which integrates both On-star, the telephone and the Stereo. It also works with the external amplifier to power it on, if a call comes in but the stereo head unit is off.

Re: Why not use the Telephone input?

The other thread you saw, was talking about 9-3's and 900's which use a different head unit.

On the 9-3 the head unit has a stereo Telephone input prior to the pre-amp. The line is not brought "out" of the unit, and is internally wired to both channels.

This is why they can wire into the Telephone circuit on the 9-3's, as it is really a stereo input.

Not so on the 9-5, the telephone is monophonic and the signal is duped to the same input used for the FM tuner, which is why I was so focused on doing it via the FM tuner... I mistakenly kept going back to the telephone input instead of looking for an alternative as Dangie did.

Re: Money

I have to consider this. I don't really want to do it for others, it's too time consuming unless you are set up to do a bunch of these at once...

To do it right on a one at a time basisi, will take 2-4 hours at the least, which includes assembling the external jack, breakaway cable, hollowing out a blank switch plate, radio disaassembly-re-assembly, actual wiring & finishing.

Also as an enterprise there is no way to actually make money doing this unless you are charged quite a bit.

The tape patch-in makes things a bit less prone to failure, but as such I do not want to be in the position of screwing up someone else's stereo, or having to explain having done so.

While I've never messed up any units or electronics other than, very rarely my own in experimentation, when I do work for other people there is always that risk, and I don't want to bear the cost of a failure.

I also will have no way to test a unit (thank's Saab!) prior to it's actual "burn/smoke test".
 

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okay so now you brought that up.

what is the point of the switch you were talking about for hte cassete?

you say your going to do his mod right? when you do can you please take as much pictures as possible.

their has to be a way to disable the cassete player so it doesn't have to spin.

so much work i would have figured by now Pac or PIE would have been able to get a working cd changer interface working.

would it be possible to have 2 inputs?

i just wish their was a good tutorial for the 9-5, with bigger pictures.
 

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Re: Switch

eh, I thought I explained that. Simply put, flip the switch one way, and the cassette player works normally, flip it the other way and the head unit gets it's input from the MP3 player.

Re: Pictures

Yes I will. I'll document the entire process.

Re: Disable cassette.

No unfortunately. You would at best have to rig up a circuit to fool the mainboard and this is far to extensive. It's easier just to use a "dummy" cassette.

The Capstan will spin, but it will be the only moving part, no belts, etc.

It also the Capstan motor has a rather long MTBF so I wouldn't worry about this.

Re: CD changer interface

A CD changer interface is far more work.

At the least it will require an external microprocessor or PIC that can talk to the iBus to flip on the CD changer inputs.

You also will need a unbalanced to balanced input converter, although an stereo isolation transformer of sufficient size will do for this...

No, the CD changer input while interesting, will utimately be a more complex thing.

Re: 2 inputs

Sure, that would not be problematic.

You could use a three way switch and provide two jacks, or if you really want to get fancy, add a small resistor/diode network to permit both inputs to operate at the same time... why would you want this though?

Remember the phone harness input would still work with all of the above, and Onstar, handsfree, etc. still will all work properly!
 

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RE 2 inputs -

I have sirius and a mp3 player. so would be nice to keep one hardwired and plugged away, then if friends bring thier ipod just plug it in and swith to an aux input:)
 

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In your case both inputs do not have to be active at the same time, so adding a second jack is simple... instead of a two way switch, we just use a three way switch.

Position 1 = Tape Player normal operation
Position 2 = Aux 1
Position 3 = Aux 2


From a hardware standpoint

------
|......|--- To "upper" (or rightmost) side of removed resistor
|......|
|......|--- To "lower" (or leftmost) side of removed resistor
|......|
|......|--- To MP3 player left channel
|......|
------

On a DPDT switch you would have two rows of the above.

In one position the upper two points are bridged. In the other position the lower two are bridged.
 

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dangie, thanks for your efforts in this! Surely they're not going un-noticed.

opjose, thanks for your improvements on this, and offers to re-photograph the process.

I'm amazed this could even work!

As another small improvement, could you use a regular cassette tape with the "tape" removed? Those cassette adaptors are great, but they can add some noise and develop a grinding noise over time within the gears inside the adaptor. If we could use a "tape" without tape, than the motor would just spin freely and I think the end result would be less operational noise from the deck. (It would be as quiet as the CD player, instead of sounding like there was a tape in there).

However, I wonder if only having 1 side of the cassette tape spinning would cause the cassette deck to think the tape was being eaten or something.

Also, admittedly I haven't had a cassette in my head unit for awhile, so maybe the noise I'm imagining is significantly quieter than I remeber ;)
 

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Yes you can use a regular cassette and "adapt" it at will.


However SOME of the cassette adapters already have fewer moving parts or engage the tension sensor and capstan in a way which prevents the spindles from having to turn with any resistance.
 

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I think you just answered my question 2 ways :D

I'm taking about the capstan turning one of the reels in a cassette, and that's it. The other reel on the cassette wouldn't move, and there would be nothing pushing against the cassette deck read head. If something needs to engage a tension sensor, than I don't think this would work.
 

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opjose said:
Yes you can use a regular cassette and "adapt" it at will.


However SOME of the cassette adapters already have fewer moving parts or engage the tension sensor and capstan in a way which prevents the spindles from having to turn with any resistance.
stop talking get started and get your pictures up :)
 

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Saaby said:
I'm taking about the capstan turning one of the reels in a cassette, and that's it. The other reel on the cassette wouldn't move, and there would be nothing pushing against the cassette deck read head. If something needs to engage a tension sensor, than I don't think this would work.
Eh, the capstan drives the tape. The capstan is the thing that engages the rubber roller wheel.

Usually this the part which sticks out and is visible is the motor shaft itself.

In turn the capstan provides motive power for the engaged spindle... be it left or right, via a rubber belt or gear.

Most decks, including the Saab's have a tension sensor as well. If the tape does not push on the sensor than the unit assumes that the tape is broken.

The cassette adapters deal with this.
 
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