Re: Disassemblina
The disassembli- described in the microphone.
Attention: -~-
Neumann-Information 1 and Cleanina of Neumann Condenser
88043I April1988
Microohones
and capsule head is delivered with each
impedance and dirt voltages.
Cleaning Parts of the circuit diminish
amplifier:
may not be touched. 4lready minimum grease the isolation figures and Cause noise
- of the microphones in operating instructions amplifiers which are
It is by no means allowed to tauch with the finger the contact and isolat- ing elements for the connection of the capsule head. Also the other high quantities
- the microphone tan
Existing dirt on components and contacts tan be removed by means of a soft brush using a detergent on the basis of Freon, Kaltron or Frigen.
Microphone capsules: -
The microphone capsules of U 89 i, TLM 170 i and the KM . . . miniature micro- phones are constructed in a way that the total surface is connected to
0 Volt. For this reason these microphones are extremely insensitive against dirt and atmospheric influences and should not be cleaned.
When microphone capsules had to be constructed in a way that the isolatingareas between the electrodes could be reached by dirt (the large double membrane Systems of U 67, U 87 (A) i, SM 69, SM 69 fet, USM 69 i, IJ 47 fet) after a long period of Operation noise voltages may occur. For cleaning the membranes the capsule has to be removed from its protecting grille. At t-he U 67, U 87 (A) i, U 47 fet microphones the 3 mounting screws at the lower plate of the capsule head have to be removed and then the complete capsule assembly tan be removed from the capsule head.
At the microphones SM 69, SM 69 fet, USM 69 i the disassembly of the protect- ing grille is more difficult:
The black dot on the upper part of the grille (position O”) has to be removed. Behind the opening a spring is visible, this spring has to be pressed back by approximately 1 mm, the grille tan then slightly be lifted
at the front side. Now the grille has to be turned by 180°, then another
spring becomes visible which has also to be pressed backward, now the complete upper part of the grille tan carefully be removed. To prevent the springs to be lost these should also be removed. The complete capsule
assembly tan now easily be removed from the lower part of the grillle.pto.
Every membrane water. The water soft blott ing-Paper.
a very soft
tan then be to be repeated
is brushed with the dissolved dirt This procedure has clean. Those capsules be exchanged.
brush with distilled removed with very
carefully
with
the capsule this method
Cleaning the These solvents For careful
is really have to
several times unt il which cannot be cleaned by
membrane are too
by means of solvents
is not allowed fugitive.
and inhomogenit ives may rema in
cleaning membrane;
thinly then no
liquid and time remains
on the
solvents
solvents
condense
Besides that the use of solvents bears the risk that the mechanical tension of the membrane is influenced.
