# Nakamichi CD400 repair



## jeffp (Jan 18, 2015)

I got this unit from a pick and pull yard. My dad needed a radio for his heep, so I glanced over on the radio shelf and found this deck. I bought it for 25.00
Then I figured I could get the wire harness easy enough, wrong! I did find the harness from Alex in Australia for 50.00, now this deck is getting expensive. So I looked up how much it went for new, and the specs, it is a nice unit.
Then I bought the mounting cage for another 50.00 
I am waiting for the wire harness to come in to test the unit. I disassembled it and cleaned it up, cleaned the cd player and all that stuff.
I did also find a new deck on Ebay, and after all I was able to find out about it, decided to buy the ebay unit, it is a new unit, a bit more expensive then the one from the junk yard.
Come to find out these were made for the USA and Europe, the only difference was with the radio, specifically the frequency spacing of the channels, the EU deck has a 9KHz freq spacing, and the US had a 10KHz spacing, for the AM. 
Ok, so try to get the service manual, or the schematic, no dice!
Ok now I get to do it the hard way and start pulling the chip datasheets. So I get the tuner dats sheet and start going through that part. 
Well pay dirt, seems what needs to be done is a simple oscillator change and I will have a tuner that works here in the US. Turns out to be a very easy fix there. I am still not sure about the front panel display, and if the digits will be ok, but at least not the thing will tune the AM stations when I get the new part.
Talk about hard to find stuff, there really is very little out here for this deck, but I think just maybe it will work out and if so I will post the changes needed to retrofit the unit, and others for the US tuning.


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## ATOMICTECH62 (Jan 24, 2009)

The display will show whatever its tuned to.Usually to change the frequency all that is required is to add or remove a resistor.Sometimes its just a jumper labeled R.
Unless its extremely old,then it will need an oscillator swap.


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## jeffp (Jan 18, 2015)

I looked up the AM/FM Ic as a start to try to get the unit to US tuning standards. According to the data sheet the difference between the 9K and 10K freq separation/stepping is the oscillator. the 9KHZ for the EU unit is a 10.35MHz xtal oscillator. the US 10KHz stepping is a 10.25MHz xtal. The data sheet shows a 10.25MHz crystal. the unit I have has a 10.35MHz crystal. So I will order the crystal and go from there. I did notice some additional resistor strapping areas on the main board. I hope they don't need any changes. I cant find a schematic for the unit. If you know of a source for the schematic I would appreciate the lead. Really I would like to get the service manual but I am not holding my breath. I figured if the front panel need some changes, I could just swap that out. I bought a used part off of Ebay, missing parts, but all I need is the circuit board. So we shall see what is up. Just waiting on parts, harnesses, and the new deck to get to me. 
I keep all of the service info for all of my gear, but I got this one just a little to late in the game I think. 
I really like the unit and look forward to getting the new unit for my car. I also bought the EC200 and EC200H crossovers for my car. I am going to push a Fosgate power 300 mosfet amp and 8" fosgate DVC's and a good quality amp 300 watts as well into a set of 10" fosgates in a box in the back of the car. 
The only bad thing is that 280zxt Nissan is really bad for mounting speakers, and I really don't want to hack my hotrod. I have a page I did some time ago in html http://www.angelfire.com/exterme/280zxt 
Anyway, I just love a challenge, and when it comes to electronics, it goes one way, MY WAY.


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## ATOMICTECH62 (Jan 24, 2009)

This is a link to a schematic.It is very hard to read but there is a legend at the bottom of the page.
What till the word "processing" under the picture of the schematic changes to "Get Manual" then click on it.

NAKAMICHI CD400 SCH Service Manual free download, schematics, eeprom, repair info for electronics


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## jeffp (Jan 18, 2015)

ok I have looked at that schematic before, but could not pick it up. Thank you for the help on that one. The schematic is mostly there LOL. I will have to look at it more. I don't quite see the tuner section. but then again the tuner section just may not be there, as it is a subassembly of the main board. 

I have been in contact with the seller of the cage to me, and he has two bare decks, no front face plate or wire harness, but the basic deck is there. He had offered to sell both units to me for 100.00 now I'm thinking that just may be the way to go to get both units up and running to the US tuning on the tuner. He said they have skipping problems, I hope that is not an issue with this deck. 
I can repair just about anything, but bad design is a challenge. 
Thanks for your help on the drawing. I will keep up on this thread.


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## jeffp (Jan 18, 2015)

SO I bought the mounting cage for the deck off of Ebay from WoofersEtc. The cage was used, but it was supposed to be new. I sent a mail regarding the problem. I was contacted and they were very apologetic about the whole thing and offered to give me the front plastic finish piece, good to go. Then I get another email from them after some emails from me. They offered me two CD400 decks without the front face plates for 100.00 shipped, US models, with the cd player in them. I also asked if they had a service manual, and they said if they had one it was in a foreign language, I said NO PROBLEM. So if they have the manual they will throw that in to.
Now since I have jumped off this cliff, I have the ability to make three units work. I bought the new unit from Slovakia, the front face plate from Ebay, the complete unit from pick and pull. now the two chassis units. SWEET
I can do the tuner upgrade with no problems at all, I have a sample model to check everything out with to do the mods.
I sure hope this thing is worth it LOL


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## jeffp (Jan 18, 2015)

*Re:best two out of three*

I got the two nak bad decks from woofers and began my repairs. I was able to put together two units from the three decks I have gotten. I would be able to repair the last deck, but it needs some gears that I can't get for the unit, so I guess it will be a parts unit for the future.
From what I can gather and observe the problems stemmed from a dirty deck, and lube that has gotten hard and stopped doing its job. So when the deck would not work correctly, the cd was pushed into the player to hard and broke two load gears, it was all over after that, the cd would not function. Plastic, why is it so popular, it never lasts over the long haul.
Anyway, so I got two decks now, the second deck face plate is not that great, and missing some push buttons. I did disassemble the part, and repair the damaged electronics, but I am missing the cd eject push button, but the face now does work.
I love repairing car stereos, just was a day short on getting parts for these decks.


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## brump3 (Jan 15, 2008)

very good


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## jeffp (Jan 18, 2015)

Ok I got the new deck in a few days ago. The unit was configured for the RDS system, so the AM would have the 9KHz channel(frequency) spacing for the European radio stations, basically NON US frequency spacing of 10KHz.
So using a US model unit, I was able to convert the unit to US standards.
The main board has two logic resistors, one resistor sets the frequency spacing for the tuner. The second resistor determines the display back light display text function red, amber and green. The RDS unit has RED LED's and green LED's. So in the front panel selection you see red and green text possible combinations. The main board resistor changes the RED text selection to Amber text being read from the front panel. However, the front face plate has red LED's and green LED's, so if you change the display readout to Amber and green, the back lite will still be Red and Green. You will have to change out the red LED's to amber LED's.
Also regarding the front panel, you have to change five resistors from 200 Ohm to 120 Ohm parts, after you convert the main board, as the front panel function switches will no longer work, except the volume control. You can't even turn the unit off without the resistor changes.
The main board as I mentioned has the two logic resistors to change. one is removed for the back lite to change the front panel display text from red to amber. The second resistor for the frequency spacing is removed and a zero ohm resistor, or jumper wire soldered in.
The second area on the main board is the RDS chip is removed, the crystal oscillator, the zener diode, a load resistor, and finally a filter capacitor, all are removed. I think removing the oscillator would be good enough, but I did not want to play around with unknowns in that regard, so I removed the chip, the power to the chip as well just to be on the safe side.
The last thing to remove are two resistors and two decoupler capacitors near the audio amplifier on the backside of the board. The two resistors and caps, feed the beeps from the RDC chip into the audio amp.
Fortunately, the tuner does not require any modifications, and will work just fine with the added frequency bandpass, thank God. I was hoping that would be the case, and it was. Re-aligning the tuner although would have been fun, would have been a pain in the butt LOL. 
So there you have it folks, not to much work to do, but some to convert to the US model unit.


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## BorisA (Dec 29, 2017)

Hi all 
I have a Nakamichi CD400 also. Bought it used for my old BMW E30 because of the look and the sound. It is a European version. But the radio has a problem. It drains my battery  . I measured the current in the off state. The radio draws exactly 320mA. Can someone give me some advice, how to repair it?


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## jeffp (Jan 18, 2015)

I cant really tell you how to repair a radio. But I do have a chassis and cd mech parts I will sell you. I did a unit for my dad, and bought a unit with the RDS off of ebay, I converted the unit to US tuning. I also have a new wire harness I bought as well. I also have a new laser for that skipping problem you mentioned. So let me know if you are interested. 

REGARDS: Jeff Priddy


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## BorisA (Dec 29, 2017)

Found the cause of the current drain.  You will find it in the schematic as the part under the name Q470. It is a PNP power transistor. When i measured the base emitter and the base collector junction it seemed ok, but somehow it still leakage current from the collector to the emitter in the off state. I replaced it with a different part since the PNP 2SB1142 is obsolete. I used the PNP BD440 with a Mica Insulator since the cooling surface is connected to the collector. 

I hope i solved also the skipping of the CD. I just cleaned the lens of the CD player. But you must be careful when disassembling it while there is allot of small parts and springs that can get lost.

I hope this helps anyone else with the same problem


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## MatthewK (Feb 3, 2018)

Useful thread thanks. I registered because I'm looking for a mounting cage for a CD400 - including the surround - if anyone has one they'd part with please send me a PM.


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