Alpine CDA-9811 issues Where to start?

[jeffshort2000]

Yes it is a 4volt pre-out unit.
There are a pair of green RCA cables which are labled "sub -w out' the front and rear are on the back panel and have a clear(white) ring around them.
There is a choke box with the fuse on the main power per the manual, but I do not think that it is a power supply. here is a link to the manual:

http://safemanuals.com/user_guide_i...l_ALPINE_CDA-9811 @@ CDA-9813 @@ CDA-7811.htm

 

[jeffshort2000]

After some more checking with my volt meter, it appears that the Vee of the op amp chips goes to ground and the Vcc is the missing power circuit. There does not seem to be a +/- differential supply to these op-amps.

I will have to tear it apart further to trace down where this supply is coming from as it seems that the thru-holes are under the chip. Hopefully I am not checking for the wrong supplies!

Thanks for all the help so far, and any that you can offer in the future of this project! - Jeff

 

[ppia600]

Maybe if the rca outputs on that unit are floating ground, they could have been damaged when in the other car? I've seen many amps go bad and send voltage through the rca cables' shield leads and toast radio internal grounds. Maybe something similar happened to yours? They were usually (not always) crappy amps though, like power acoustik and similar flea market stuff. Did you use amps in the other guy's car, or just the speaker leads?

 

[jeffshort2000]

We used the speaker leads, the strange thing is the tuner does not work for the tune up/down buttons anymore. That leads me to beleive that there may be a missing voltage somewhere.

I do not smell anything burnt, I have a feeling that it is a diode or cap that may have opened up. The chip that has 'Alpine' on it seems to be getting warm (not hot) though... but, all of the other processor functions seem to be ok. Maybe that voltage is driving the tuner module also.

 

[Perry Babin]

Are there any buttons that feel 'stuck' or otherwise don't feel quite right?

Some head units will lock up of any button is stuck down or shorted internally.

 

[jeffshort2000]

All of the buttons beep when I press on them.

 

[I Am An Idiot]

You will never guess what I found while cleaning my bench. That's right a CDA-9811. I have no time today to see what is wrong with it. But tomorrow I can hook it up and look for the power source for the op amps. These units do not have the outboard supply that must have been an older model.

 

[jeffshort2000]

Thanks! that will help so much to use it as a reference.

I am looking for parts if you are selling them. Need the power connector, mounting cage and bezel also. using a JVC currently and it does not lock correctly.

Thanks,
Jeff

 

[I Am An Idiot]

33C01797K01 TRIM RING IN STOCK $6.09
01T65571Y02 WIRE HARNESS IN STOCK $13.74
The mounting sleeve has been discontinued

The above are available at Pacific Coast Parts pacparts.com
1-800-421-5080

 

[ppia600]

/\ I've repaired several kenwood amps and decks with parts from them, great company!🙂

 

[jeffshort2000]

Thanks, That is where I will go for the parts!

 

[I Am An Idiot]

There are 3 op amps in that deck the 2 quads that you saw and a dual one in the front left corner of the board. They get power from the smaller chip mounted to the heat sink, next to the output IC. IC801 the power pin is the one just beyond the 1 of the marking on the board. With the rear of the radio up and you can read the IC801 the pin directly to the right of the one. Pacparts lists the frequently purchased parts for each unit. This part is listed. That means it has failed on other units.

51T65147Y01 IC LOC# IC801 (HA13165) IN STOCK $9.46

 

[jeffshort2000]

By golly you have gotten me in the right direction!!!!

Pin 1 is an output, pin 8 is b+. I found that the op-amp Vcc is connected to pin 10. Pins 8 is at 11 v and 10 is at 0 volts.

The big silver cap (100uf?) looks good, it passes the dvm bounce test and there is no short between the Vcc and ground. It reads infinite.

I think that we got it now. I just edited this cause my brain did not equate that if the antenna and accessories are getting power the IC must be getting it from somewhere. My counting pin was off!

Am I correct in the Vee of the quads are going to ground, or is that the reason for this chip opening?

Here is the datasheet for that IC

http://www.renesas.com/fmwk.jsp?cnt...=/products/assp/for_audio_equipment/car_audio

 

[I Am An Idiot]

Pin 11 of the Opamp is supposed to be at ground.

 

[jeffshort2000]

So, If I check the voltage on pin 11 of the IC801 device and there is voltage, when the tuner is on, I know the chip is bad and not something in the line.

Can I run this device without the heatsink for a few minutes without the whole unit smoking?

Thank you so very much for your help. I hope that i can assist you with a project in the future!

Jeff

 

[jeffshort2000]

I checked pin 11 of IC801 and it is at 2.10 volts during the tuner mode. I did not check in CD mode but have to assume that it will go to 4v. I will check that tomorrow.

Guess I will be ordering parts now!

Thanks again,
Jeff

 

[I Am An Idiot]

Pin 11 of the quad op-amp is ground. I have no idea what pin 11 of the chip is. On the laptop and just realized I have no Adobe Reader on it. I will check it later today.

You wrote. Am I correct in the Vee of the quads are going to ground, or is that the reason for this chip opening?

That is why I wrote Pin 11 of the Op Amps are supposed to be at ground.

 

[jeffshort2000]

Sorry, I did not mean to be confusing with bouncing between pins on 2 chips.

Just wanted to make sure that Vee of the quad op-amps was indeed ground and not a negative voltage.

There are actually 3 more op-amps that are the same as the one in the front left corner on the bottom of the board.

Pin 11 of IC801 is the control pin. The state toggles between Low, med and high per the data sheet. Low is amp off, Med is audio and high is CD on.

Thanks for the help!

Jeff

 

[I Am An Idiot]

Preferred voltage would be a negative voltage. But they have no room to build a power supply. So they use ground.