Daniel wrote:

I just uploaded a close up photo of a 4 track recording head. From the photo
below, can you please tell me what condition do you believe the head to be ?
(Excuse the lint from a cotton swab ).

http://members.shaw.ca/sivle/DSC00045.JPG

You can't tell from the photo [and until I noticed that you mentioned lint...
all I could think of was that the head needed a cleaning]. It doesn't look like
it has an appreciable wear pattern... but you should really send the stack to
JRF Magnetic Sciences http://www.jrfmagnetics.com for a real evaluation... they
have the equipment and the expertise to give you a real determination of it's
fitness.
--
Fletcher
Mercenary Audio
TEL: 508-543-0069
FAX: 508-543-9670
http://www.mercenary.com
"this is not a problem"

Mike Rivers wrote:
In article
writes:

I just uploaded a close up photo of a 4 track recording head. From
the photo below, can you please tell me what condition do you
believe the head to be ?

Mighty hard to tell from that photo. What are those four light brown
blobs along the right side of the pole piece? They almost look like
pits in the filler material.

I think they're just a reflection.


You really need to get in there with a microscope and look at the gap
to tell much more. Or just remove it and send it to JRF.

But you're right that it's kinda hard to tell.

Daniel

Fletcher wrote:
Daniel wrote:

I just uploaded a close up photo of a 4 track recording head. From
the photo below, can you please tell me what condition do you
believe the head to be ? (Excuse the lint from a cotton swab ).

http://members.shaw.ca/sivle/DSC00045.JPG

You can't tell from the photo [and until I noticed that you mentioned
lint... all I could think of was that the head needed a cleaning].
It doesn't look like it has an appreciable wear pattern... but you
should really send the stack to JRF Magnetic Sciences
http://www.jrfmagnetics.com for a real evaluation... they have the
equipment and the expertise to give you a real determination of it's
fitness.

Ok, thanks! I'll start by cleaning the head

Daniel

Daniel wrote:
I just uploaded a close up photo of a 4 track recording head. From the photo
below, can you please tell me what condition do you believe the head to be ?
(Excuse the lint from a cotton swab ).

http://members.shaw.ca/sivle/DSC00045.JPG

All I can tell from this is that you REALLY need to clean your heads.
Don't be afraid to use some elbow grease. Use xylene and rub hard.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

Daniel wrote:

You really need to get in there with a microscope and look at the gap
to tell much more. Or just remove it and send it to JRF.

But you're right that it's kinda hard to tell.

Look at the gap with a 50x magnifier. If it's wider on one track than
the other, throw the head away.

Check the flat section on the front of the head. Is it very flat, or a
little flat? You might be able to judge wear a little bit from that.

But the real question is how does the machine align? If you can get response
flat to 16 KC, and the 16 KC tone doesn't jump open and closed on the scope
constantly, the heads are fine. If you can't get the azimuth alignment right,
you may have a tape to head contact problem from too much head wear. If you
can't get the response flat up there even with the playback EQ control cranked
way up, you probably have a bad playback head.

Record heads are a bit harder since the bias also affects things, but you can
learn a lot just from looking at the 16 KC tone on the test tape in sel-sync.

The only way to find out how much real life is left on the head is to measure
the inductance on a bridge. JRF will do this for a reasonable fee.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."