Add an Ipod Input to tape player of SC-815/816

[taxi]

Hi!
I just wanted to add my discovery about solder audio cables directly onto the circuit board in my SC-801: I got really crappy sound quality, until I disconnected the audio signals from the tape deck. Can't remember reading anything about the importance of this!
Thanks for this and many other threads about this on this site!

[xHeart]

This thread reads like a professional ham radio project.
I have 815. I can't turn it on because the volume is blaring, the knob turns but the volume doesn't change.

Feeling lost on the road without the talk radio.

[figmentj13]

Ok... So when doing this I have noticed when plugging in my phone I create an electrical hum that sounds like it's coming from the alternator... Has anyone done this project before and have you experienced the same results?

[bugleg]

Yes, I can't use this while my phone is plugged in, and the hum appears to be RPM dependent.

[cn90]

I need to ask the guru the obvious questions...

Option 1: do this mod: take the radio apart and solder the 3 wires...

Option 2: go to the store and buy the cassette adapter ($6 at local stores) that has the mini jack attached. This does not require any work at all...

So the obvious question in terms of sound quality (I will be playing MP3 music from iPod, iPhone): does option 1 gives you better sound?

[kcodyjr]

If you're getting RPM-dependent hum, you have a weak ground strap or ignition coil.

Disconnecting the tape circuit is indeed important for sound quality. The magnetic pickup has electrical resonances that would screw with the injected signal much like putting a series of Coke bottles in front of the speakers.

There's no such thing as an ungrounded audio cable. Left, right, ground. If it doesn't have all three, it isn't a proper audio cable. That said, ground can be any type of conductor, doesn't have to be a braided shield or anything to work.

Somewhere along the tape path, there will be a cam that detects the presence of tape under tension. If it doesn't get any, it assumes the tape is being eaten, and ejects it. Look for the cam and either simulate its being held under tension, or short its contact switch.

Edit: Correction. Any plain wire will work for a signal ground, but braided shields do help to reject radiated interference. This is especially true when other, unrelated wires are running physically parallel. It does not help with noise introduced on the ground rail by the ignition.

[cn90]

I just did this mod for iPod, a few comments:

1. As already mentioned, the very first post photos were WRONG, if you do it that way, all you get is sound from the (R) speaker, and nothing from the (L) speaker. I was in hurry and didn't read all the posts. So live and learn.

2. The CORRECT way is the photo by bags519 above. Note: I soldered the Red and Black wires as shown, but the Ground wire: I didn't solder it, instead I used the screw as in the first photo.

3. Use fine-tip solder.

4. If you are good at soldering, all you have to do:
- Only remove the TOP cover (2 screws), then remove CD player (d/c ribbon connector)
- Leave the cross bar and the cassette player alone!
- Then feed the mini-jack cable through a hole in the back of the stereo, then solder them as in the photo by bags519 above.
- If the cassette (gutted of tape) is ejected, then reverse direction as people said above.

This way you save the time removing the cross bar and the cassette player.

Hope this helps others...

[matthew1]

CN90, (and EstVolvo and Bags519 if you're still reading), is this photo http://i1123.photobucket.com/albums/l54 ... 93ed6a.jpg the incorrect one that gives only one channel? If so I'll edit the head post and insert Bags'.

[cn90]

Yes Matthew,

That photo was incorrect.

I have put together a composite photo showing both the incorrect and correct method.
Again, no need to remove the cross bar or cassette player. Once the CD player is out, you can solder it using a fine-tip soldering gun...

iPod.JPG (146.07 KiB) Viewed 3895 times

[xHeart]

Just to verify if the ground wire (green) fastened at the philips screw on the frame?
Daughter would love this.