Background:

        The jack fields used in most broadcast and studio consoles employ a variation on a connector developed originally for telephone switchboards. The main feature of these that has kept the design active has been the amount of switching that can be hung-on the jack, permitting very involved interrupt or bridging variations to take place upon the insertion of the plug.

        However, by its very nature, the sleeve contact does not always make a good connection, and while this contact is used for the shield, and the other contacts maintain the balanced line conditions in most applications, even the presence of rectifying films in a shield circuit can cause problems with RFI.

        Good contact is of course necessary in the signal path, when it is not made, there can be problems with poor signal to noise ratio, microphonics, RFI, and even distortion are present.

Existing solutions:

        The treatments previously available fall into three general classes; cleaners, protective oils, and contact-plating-material stabilizers. Most cleaners are based on solvents such as perchloroethylene, or one of the Cellosolveves(TM), either singly or in combination. The protective oils range from silicones through vegetable oils. The third class would be a material like poly-phenyl-ether or something similar. A possible fourth class could the combination of any of the others, including a possible solvent.

        However a problem often encountered with oils is their tendency to "Varnish" or for a tough film on the surface of the connector. This is especially aggravated by the presence of sulfur from the high sulfur or free machining brass stocks used in the manufacture of many of the jack field contact parts. Quite a number of the vegetable oils (such as palm oil) can be cross-linked (literally vulcanized) by free sulfur, forming a sort of crummy varnish-like deposit in the process.

The use of Stabilant 22--22A--22E:

            Where varnishing has been experienced it is important to clean off any such deposit from the connector before applying Stabilant 22/22A/22E. We would suggest the use of any of the cleaners which do not contain silicone or oil of any other kind.

            By then applying a thin coating of either Stabilant 22, Stabilant 22A or Stabilant 22E, to the ring tip, & sleeve contacts (or to the tip and sleeve contacts of the 2 circuit plugs) and only will the signal to noise ratio be improved, but harmonic distortion can be reduced as well.

            Be sure to apply Stabilant 22/22A/22E to the switching connections in the jack field as well. The use of one of the proprietary cleaner/applicators such as the burnishers made by Vertigo Recording Services is advisedl**

Results that are to be expected:

            It is suggested that only one channel be treated initially and compared with an untreated channel. The difference us usually audible as a smoother more musical sound on the treated channel.

Reference:

    **Vertigo Recording Services

    12115 Magnolia Blvd.

    North Hollywood, Ca 91607, USA

    Revision 4

NATO Supply Code 38948

15 mL of S22A has NATO Part # 5999-21-900-6937

        The Stabilants are patented in Canada - 1987; US Patent number 4696832. World-wide patents pending. Because the patents cover contacts treated with the material, a Point-of-sale License is granted with each sale of the material.

MATERIAL SAFETY DATA SHEETS ARE AVAILABLE ON REQUEST.

        Stabilant, Stabilant 22, and product type variations thereof are Trade Marks of D.W. Electrochemicals Ltd.

    © Copyright 1987, '88. '89, '90 - D.W. Electrochemicals Ltd. This note may be reproduced or copied, provided its content is not altered. The term "contact enhancer", © 1983, 2000 Wright Electroacoustics.

    NOTICE: This Application Note is based on customer-supplied information, and D.W. Electrochemicals is publishing it for information purposes only. In the event of a conflict between the instructions supplied by the manufacturer of the equipment on which the Stabilant material was used, and the service procedure employed by our customer, we recommend that the manufacturer be contacted to make sure that warranties will not be voided by the procedures.

    While to our knowledge the information is accurate, prospective users of the material should determine the suitability of the Stabilant materials for their application by running their own tests. Neither D.W. Electrochemicals Ltd., their distributors, or their dealers assume any responsibility or liability for damages to equipment and/or any consequent damages, howsoever caused, based on the use of this information.

    Stabilant, Stabilant 22, and product type variations thereof are Trade Marks of D.W. Electrochemicals Ltd.

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