Added an auxiliary input to my factory deck...

[footy14]

buzzing sound when tape player turned on

I did this mod today. Soldered individual wires on the left and right pot's and a ground with the left pot, however, when I put a tape into the tape deck, I immediately get a loud buzzing sound through my speakers.

When I soldered the right pot, I got a little too much solder, and connected a nearby contact. I tried correcting this, and thought that I removed enough of the solder to disconnect the two contacts.

I can hear music playing from my iPod, but it sounds terrible, and is completely drowned out by the buzzing sounds.

I didn't have time to pull the deck and double check the connections, but any thoughts or suggestions before I dive back in would be welcomed.

Also, what method did you use to connect the female aux port to the deck wires that were soldered on? I take it, you purchased a female 'Y' connector, stripped the 2 ends and either soldered or fastened with speaker quick connects?

Thanks

 

[fish0281]

footy, did you disconnect the tape head? Sounds to me like that is still hooked up and would be the cause for your interference. There should be a flex circuit you can unplug coming directly out of the tape deck head...

I purchased a female 3.5mm standard headphone connector (radio shack) and hard wired that directly to the POTs... the connector has three connections: left, right, and ground. From there, I can just use a male-male headphone wire and connect an ipod/droid/etc.

 

[footy14]

If the tape deck connection is the orange ribbon, then yes, I did disconnect it. I have some time tomorrow to look at it, so I'll post once I've fixed it, and discovered what the problem was.

Thanks

 

[nissanh]

Use a cassette adapter (a cassette with a 3.5 mm jack), $3 on ebay Works the same way.

 

[fish0281]

Use a cassette adapter (a cassette with a 3.5 mm jack), $3 on ebay Works the same way.

It's the same in that it plays audio through the factory head unit. However, tape converters sound like $hit.

This is hardwired into the circuitry and sounds as good as a CD ... it's the equivalent to the factory-installed auxiliary input that comes on most new vehicles.

Did you even read the thread?

 

[footy14]

Yah, I wan't to avoid the cassette head jack for 3 reasons....
1)we aren't living in the late 80's anymore (remember those CD walkman to tape deck stereo connectors)
2)the sound quality is tragic
3)I don't want wires dangling out of the head unit.

I plan on running the aux port connection through either the ash tray, or underneath the stereo where there is the small compartment area. I prefer a nice clean stock look.....and once I get this all dialed up properly, I'm sure I'll be happy, especially because I have a road trip coming up soon.

 

[footy14]

Well. I had a good look at the stereo today, and tried to do some trouble shooting, but no luck in getting the aux jack to work. I have posted some pictures of what I have done. I'm thinking that my issue could be that I have used a 3 RCA into 1 aux jack (red, white, and yellow). Do you think it could be that I am not getting a ground, due to the cord being a 3 RCA into one?

Any ideas or thoughts?

Thanks. Pics below.

 

[fish0281]

It looks like you wired both leads (left & right) to the same POT? I have one lead on each... I used a multi-meter to figure out which connector (on the pot) was ground using the continuity function - test between a known ground and the pot connections.

I'll see if I have a better pic of my wiring & post it up later tonight...

 

[footy14]

I'm kind of at a loss now. Here's what I got:

I confirmed that I did have the left and right connections soldered to each L and R POT by touching the leads to each of the POT and verifying sound coming individually from the left side and right side.

My issue, when I connect individually to either the L or R POT, I can here a very low level of music, the strange thing is, this is without grounding any wires. However, if I take one of the other 2 remaining wires from the AUX, and touch it with my finger while it's playing, and only one POT is hooked up, the sound is amplified and more clear...not great sound, but definitely not distorted.

The problem comes in, when I attempt to hook up both L and R POT's at the same time....the sound becomes completely distorted, and the music can no longer be heard.

I'm stumped.

So, to recap: One connection to one POT = very low sound
One connection to one POT while holding another connection with my finger = louder, more amplified sound (to the corresponding POT side)
Both POT's connected while holding the last connection with my finger = complete, loud, distortion.

Any audio experts out there care to pipe in? I thought this would be straight forward.....

Thanks

 

[fish0281]

I didn't really notice or understand what you meant before about the 3-plug cable you're using... that's likely your problem. That third wire is NOT a ground, it's meant serve some other active function (like video or something).

Get a normal headphone extension (male-male) and one of these. Wire up the connector like you have above (one wire to each pot and one wire to the ground of a pot) and then plug it all in and test it.

 

[changedsoul]

jh91304 - I have the exact Radio you have. Have you found your problem yet? I was doing some tinkering on mine and found those pots to not be what they are on the previous posters working mod. I think they are some sort of gain adjustment for the pre-amp, no signal going through them. Maybe a bias for the pre-amp circuit?

Anyways when I touched any part of the pot with my oscilloscope, I heard a radio station bleeding through somehow. I wasnt able to see any signal on any pin.

I did find a signal point right in front of the two pots, labled TP831 and TP821. I disconnected the tape players head, and injected my ipod line out to these points. I heard music. It sounded good. It was not as loud as the cd players signal though, so there maybe be some better place to jack in.
The volume was sufficient through.

I could jack into where the cd input goes, but I havent played with it and not sure if I need a cd in to enable the cd player audio.

 

[changedsoul]

Here are some pics of where I soldered my Inputs.

 

[F*ckTapes]

I just did this mod

So I did this mod yesterday and here is some advice:

• You need to pull the face plate to get access to the screws to remove the metal cage
• they are torque screws and you need a long torque driver
• if you plug the unit in without the cage it doesn't work
• there needs to be a cassette in the deck AND PLAYING for this to work.

so if your tape deck is broken don't do this. mine tries to flip the tape over and over before ejecting. 4 hours of work for nothing. The sound is great when it the tape is playing but....

http://www.mysmiley.net/imgs/smile/animated/anim_20.gif

 

[IBallEngineer]

I listen to a lot of streamed music (Slacker & Pandora primarily) and I did not want to buy an aftermarket head unit because I figured this is close to free and I don't really care for the looks of aftermarket units...

Basically, it goes like this: remove the bezel around the shifter, then the bezel around the radio, take out the radio and remove its metal housing. Then you just need to remove the ribbon going from the tape player's head and solder in a suitable auxillary input unit to the post-amplified circuitry (not where the ribbon connects).

Each model head unit may have somewhat unique configurations, but it should be easy to find the potentiometers and test which connection leads to the audio output... Here are some pics of how I did it with my 2001 model head unit (AD6803).

(Does anyone know how to embed picasa photos to a post?)

https://plus.google.com/photos/104558386343784620523/albums/5729128934414818177

The only thing I purchased was a female 3.5mm connector and a male-male headphone extension cable from Radioshack. Also, a tape needs to be in the tape deck for this to work, but since the head is not connected to the circuit board, the tape's audio output won't be played.

I still have some feedback noise (ground) if I charge my phone while playing music and I would recommend using a covered ground wire from the 3.5mm female to the head unit. All in all, the sound quality is great and it's a super easy mod!

You could add a ground loop isolator

3 5mm Headphone Jack Audio Noise Filter Ground Loop Isolator 1 8" Hum Suppressor | eBay

 

[cbcooler1]

Where on the CD board did you find the R/L at? I've tried on the Tape deck, 98 4Runner and have had no luck like others on here that get a lot of noise, I've tried to the pots and other connections on the tape board, guess I should try this now.

Hey again fish0281,

Thanks for your quick reply. So for some reason I was unable to get the music to play thru the cassette deck mod. Kept trying the pots and grounding to everything. So in the end, I tried running the music thru the CD player, which actually worked. Just found the R, L, and a ground on the CD player itself and soldered the wires directly to the CD unit. The only thing is that the CD music still plays in the background, but only when you turn the aux music (my phone in this case) all the way down. But when the music is playing at normal volume it seems to cut the CD music all out, can't even hear it. Another thing I've noticed is that the aux music will play into the radio when radio is pressed, but it's definitely not a problem. Just got to know which is playing and when.

One thing tho...
While testing my aux music it sounded great, but upon closer inspection I noticed something: I tried my balance, heard left and right just fine. But then I tested out my fader and found that the middle (or F0 or R0, between the front and back) was fine, the front speakers were fine, but the rear speakers sounded very low and almost tinny. I wasn't sure if I had perhaps done something to the head unit to interfere with the rear speakers, or maybe had blown them out while testing the audio. Seeing if you had any input on the matter.

Thanks again.

 

[cbcooler1]

jh91304 & changedsoul, I'm having same issues as you had. But I do not have the TP831/TP821 connections on my board. I've tried a few locations, I have 2 boards on my tape deck, top small board that reads the head, you would think I could find a signal here. Not sure if I should look on the bottom board which feeds the wire harness going out or just look at the CD player connections instead. Wasting time on this now, thought this would be a little easier. SMH

jh91304 - I have the exact Radio you have. Have you found your problem yet? I was doing some tinkering on mine and found those pots to not be what they are on the previous posters working mod. I think they are some sort of gain adjustment for the pre-amp, no signal going through them. Maybe a bias for the pre-amp circuit?

Anyways when I touched any part of the pot with my oscilloscope, I heard a radio station bleeding through somehow. I wasnt able to see any signal on any pin.

I did find a signal point right in front of the two pots, labled TP831 and TP821. I disconnected the tape players head, and injected my ipod line out to these points. I heard music. It sounded good. It was not as loud as the cd players signal though, so there maybe be some better place to jack in.
The volume was sufficient through.

I could jack into where the cd input goes, but I havent played with it and not sure if I need a cd in to enable the cd player audio.

 

[Killer Squirrel]

Just wanted to say thanks for this, I won't be able to buy a new head unit for a while but need mah tunes! I soldered the positive lead to the tops of each pot and the ground leads to casing ground. Works great!