I am newbie here so be gentile...
I have an old Nak 505 that I purchased back in college when it was new. I just dusted it off and thought to include it in my "vintage" rack. Only problem is that after testing it out, only one channel is working. I tried various cables, cleaning RCA posts, reversing and so on. :scratch2: I am guessing that it is more than a head alignment or degaussing issue. Are there any Nak gurus amongst the clan? I would gladly box it up and send it off for a proper cleaning and re-work if it make sense.

Thanks in advance for any help or suggestions.

Bodhi

There is a poster named NAK DOC, or nakdoc. You can locate him on the list of posters and send him a PM.

There are several other Nak experts too. They will probably chime in.

And I agree, since you swapped cables etc. it isn't the heads needing degaussing. It is something else.

Need a little more information. When you play a tape, do both channels level meters light up or only one? If you plug in some headphones while playing back a tape, is there sound on both channels of the headphone or only one? If you plug in a source, a CD to the input for example, and monitor the source using the tape/source selector switch and the input level knob, do you get music to both channels on the meters, output jacks and headphones?

It sounds like this deck has been in storage for quite some time. It wouldn't surprise me that the pots and switches need a cleaning with DeOxit.

An easy way to determine this, dumb as it sounds, is to cycle all switches and knobs 30-40 times. If you do this while listening through headphones for example, and you hear crackling or scratching noises while you are moving switches and knobs, this is a sure sign of dirty switches and pots.

Let us know what you find.

Ok, thanks for advice. I did as you said and still have one channel that is very weak and muffled. The meter is corespondingly low on the bad channel. I do not have headphones to perform the test as proposed.

Is there any harm in removing the case and and applying a liberal dosing of contact cleaner? Is there a "reccommended" cleaner?

I am guessing that drive belts (does it have drive belts?) are probably old and stretched. I hear a "clicking" sound when FF or REV - any suggestions?

Mucho gracias for the help!

Bodhi

Your description almost sounds like the head is really dirty. The fact that you can hear something and show a slight signal could indicate that. I should have asked that first. Have you thoroughly cleaned the heads and tape path yet? This really is the first place to start.

Your belts probably need replacing. The 505 has quite a few belts in it, five if I remember right. Four of them are fairly generic and just about any belt of the right dimension will do. But the capstan belt HAS to be perfect to extract the full performance this deck is capable of. You really only have two choices for the capstan belt: either buy an original NOS Nakamichi OC08096C belt from ESL (last I heard it was $55) or somewhere else if you can find one, or Fred of MarrsCommunication has just come out with an exact replacement that performs every bit as good as the original for half the price- the 8096D2.

As far as contact cleaner goes, there is no harm in using it as long as you are comfortable working around electronics and know where to apply it. Unplugging the unit first goes without saying! Caig Labs DeOxit seems to be the near universal favorite and I can attest that it works very well. There are others that get the job done however.

One other thing you still need to try is feeding a source into the machine and using the tape/source switch and the input and output knobs to see if the signal goes all the way through the machine. This will help to isolate the problem.

Start with the head cleaning. You really need to look closely at them with a good light. Sometimes there is some stubborn residue on the heads that can be a little tough to get off and this could certainly account for a low and distorted signal from a tape.

Nakmandan - Thanks! I cleaned the heads with great resolve and a magnifying glass. The signal and sound level is now restored. I also cleaned the transport mechanism and the tape speed appears to be consistent. I did not measure speed though. A pencil eraser and some denatured alcohol did the trick.

Question - Is the head alignement something that is done by ear? It would appear that if one had the small speciality tool, one could simply adjust until signal and symmetry is balanced :scratch2:. Am I offbase? Where does one find the "specialty" tool?

Any other advise?

Thanks again for the help! Much appreciated.

Bodhi

It can be done by ear but I don't recommend it. Particularly since you said you are the original owner since new. Nak transports don't go out of alignment all by themselves so if this has never been out of your hands, there is no reason to think that the alignment from the factory has been tampered with.

To properly set the azimuth/height/guides on a Nak standard transport, you need special alignment tapes and unobtanium (except for a few select people) alignment gauges and a few pieces of specialized equipment.

You should NEVER adjust the head alignment without the proper equipment as you probably will not be able to get it back exactly where it started from. If you were attempting to adjust by ear to a particular tape, how do you know that tape is correct? Unless it is a calibrated alignment tape, you don't! I would only advise adjustment by ear if someone has completely screwed it up and you have nothing to lose.

Glad that a simple cleaning fixed your problem. Those are the kind of repairs I like best!:thmbsp: