Can this be repaired??

[ericpeters]

Most people won't recognize it btu this picture is an openen Audio Technica OC 9 moving coil cartridge.
As you might see the internal (very small) wiring has been overloaded and burned. So both channels are dead. You need a good magnifying glass to be able to see this. (Or a good Macro lens like I got)

Anyway, is there any change I could get this repaired at reasonable costs. The cartridge only has been playing maiximum 50-100 hours.

[Bill Fitzpatrick]

A good macro lens with a good photog using it would have resulted in a decent photo. Looks like the camera shook so who can tell a thing?

[ericpeters]

It's night, I don't have a tripod nearbye, flash did not give any decent result.
Dept of field is less than a milimeter with this type of close up picture!

I will try update it when light is back in this town.

[SY]

OK, I can't help it, I have to ask.... how did you do it?

[ericpeters]

Originally posted by SY
OK, I can't help it, I have to ask.... how did you do it?

I built the very nice and cheap VSPS (high gain) phono pre. I'm running it on 12V lead batteries, this all sounds very good for the price.

I recharged the batteries yesterday and hooked one of them with the wrong polarity.
I actually spend the entire evening building a new VSPS because I thougth this was the problem.

[EC8010]

Taking shots of cartridge internals needs a good tripod and the lens to be stopped down to f/40. Even with bags of daylight, exposure tends to be counted in tens of seconds, and needs to be bracketed. Lighting is critical - I find holding 10" square of aluminium nearby during the exposure to be extremely useful for directing light where I want it and removing shadows.

You have nothing to lose in attempting a repair. You probably need to buy a jeweller's loupe or surgeon's magnifying glasses and a really small tip for your iron. Good luck.

[Netlist]

I used to repair watches long time ago.
Some tips:
Listen to some classical music, stay very calm, heat the room at a comfortably level, close all doors, unhook the phone, clean the workspace and use a piece of nice new white paper to layout the tools you plan to use.
This, in combination with EC8010’s tips should do the trick.
Remember, you’re probably dealing with parts ten times smaller then the smallest SMD.

Good luck.

/Hugo

[EC8010]

Originally posted by Netlist
Listen to some classical music, stay very calm, heat the room at a comfortably level, close all doors, unhook the phone, clean the workspace and use a piece of nice new white paper to layout the tools you plan to use.

Excellent tips! I shall use them myself...

[analog_sa]

It all depends on how lucky you are. The external wiring may be obviously melted but that doesn't mean the coils are still ok. Very likely they are shorted in many places.

[sam9]

Possible but no guarantees. Comment above regarding coils is a potential show stopper.

About thirty years ago I managed to solder some similar itty bitty wires on an Empire cartridge that had been mechanically damaged. I was very near-sighted then which was an advantage as I could press a sheet of paper right up to my nose and focus on it. Could see the hairs on all the little fibers. On the other hand I, literally couldn't focus on my own outstretched hand! I also had a much steadier hand back then (which is odd because in those days wine helped make things steadier - to a point). Anyway, the point is you need to be able to see what you are doing and hold thew solderting instrument dead steady - it is probably do-able.

Suggestion: don't try to apply the solder to both pieces held together at the same time. Tin each separately then bring them in contact and just touch the tip of the iron to them and remove.