Application Note 8 - CATV Applications

Application Note 8 - CATV Applications

What is Stabilant 22?
Stabilant 22 is an initially non-conductive block polymer which when used in a thin film between metal contacts becomes conductive under the effect of an electrical field. This occurs at an electric field gradient such that the material will remain non-conductive between adjacent contacts in a multiple pin environment. In addition, Stabilant 22 exhibits surfactant action, as well as lubrication ability providing a single component resident solution to virtually all contact problems.

When applied to electromechanical contacts, Stabilant 22 can provide the connection reliability of a soldered joint without bonding the contact surfaces.

What are its uses in CATV equipment?
Stabilant 22 can be used wherever electrical contacts are used, whether this is in connectors, or in switches. In cable equipment its most frequent use is in the co-axial connections on the Main Line/Distribution amplifiers such as the Lindsey Equipment - Models 10-40 and 961 or on the case joints in the Jerrold units. By eliminating the effects of corroded connections, it restores service in much less time than conventional methods. In many cases it eliminates the need to replace line amplifiers having badly corroded connectors. On case joints it eliminates the need for the cleaning and metal scraping of the joint as well as the need for the over-tightening that often strips the case screws. Because Stabilant 22's use in a contact enhances the performance of that contact beyond that of an equivalent new contact, the performance improvements are often dramatic. We have been told that it makes the quality of the signal at the end of a long series of amplifiers more nearly equal that of the beginning of the chain!

In head-end equipment the improvement often obtained in color accuracy and signal to noise ratio even with brand new equipment, is sufficient justification for the material's use!

The Stabilant's performance in subscriber taps and in splices is one of improving the reliability of the connections, thus eliminating many costly service calls and improving customer satisfaction.

Stabilant 22 is also a preferred contact treatment in TV Security systems. Many installations are not easy to service, and because of the nature of the use of the system many customers are extremely critical of any erratic operation of these systems. We have been told that there is often a marked improvement in the quality of the picture and that details are much easier to see!

Why should we use Stabilant over less expensive alternatives?
Granted that the material itself is expensive, however it is unique in having a very long useful life once in place. Unlike other so-called contact treatments, Stabilant 22 will not cross-link (becoming varnish-like) under the action of sulfur based curing agents in elastomers, cutting oil residues, or the sulfur-bearing free-machining metal alloys used in some contacts. In most types of service work, the cost of the down-time involved in removing and replacing a board will be much greater than the cost of the Stabilant used to treat the board. Here what is important is that not only will the proper board treatment cure existing contact problems, it will prevent others from occurring, thus eliminating the necessity of repeating the treatment at a later date!

In other words, why do a job more than once?

In what forms is Stabilant available?
The Stabilants are available in several forms. As a concentrate (Stabilant 22), an isopropyl alcohol-diluted form (Stabilant 22A), and an ethyl alcohol diluted form (Stabilant 22E). For example, a given size container of Stabilant 22A will cost about one-fifth the amount of a container of Stabilant 22 as it contains only one-fifth the amount of the concentrate. Another form of packaging is available. Stabilant 22S packages the concentrate such that it occupies one-fifth the volume of an otherwise empty container. This allows the end-user to add his own diluent, and thus saves the added costs of shipping the diluent (e.g.: isopropyl alcohol), as well as allowing the end-user to use an alternate diluent such as one of the Freon-based solvents.
In addition a 0.5 ml vial of Stabilant 22A is available for manufacturers to include with plug-in circuit boards
What is the difference in use of these materials?
Stabilant 22 is most useful where the connections are out in the open - such as card-edge connectors or where the lubricating properties of the material are useful -such as an aid to installing microprocessor IC's or on switches. Where the connections are not too easy to get at or where the user wishes to apply the material to something such as a socketed IC (without removing the IC from its socket), it is easier to use the alcohol diluted form (Stabilant 22A or Stabilant 22E). The alcohol diluent serves ONLY to carry the concentrate into the connector.
Is it available in a spray can?
No. Why waste the material? We would like to think we are environmentally responsible and safety conscious. This ruled out the use of either a chlorofluorocarbon or highly inflammable mixture of butane and propane as a propellant.
In addition even Stabilant 22A for example, has only about 71200th the solvent impact as conventional contact cleaning solvents, over a three year time span. As Stabilant 22 contains no solvent it has absolutely minimal environmental impact and is, therefore, becoming the treatment of choice for many service organizations!
Is Stabilant 22 just another contact cleaner?
No, Stabilant 22 is a resident potentially electrically active material which through a synergistic combination of effects enhances conductivity within a contact without causing leakage between adjacent contacts. Thus large quantities of the material do not have to be "hosed" on, as is the case with cleaners.
How does Stabilant 22 work?
Contact failure is rarely caused by a single factor. Thus, treatments that solve only one problem don't necessarily offer a reliable long term solution. For example, cleaners do not prevent the re-entry of contaminants or the reformation of contaminant films; nor do they offer any lubrication. They must be used each time a connector gets dirty. Lubricants in themselves are rarely cleaners. Corrosion inhibitors are neither cleaners nor lubricants and are often specific to one type of metal or plating. Unsaturated oils used as contact treatments can cross-link under the influence of elastomer or thermoset plastic curing agents and accelerants.
While resident in the connector, Stabilant 22 performs several concurrent functions. Its very presence in the contact gap will prevent the entry of outside contaminants. It has sufficient surfactant action to lift surface contaminants and hold them in suspension. In cases where corrosion products are present, Stabilant 22 will penetrate them and prevent rectification effects. Due to its high dielectric constant it will act to form a capacitive layer which is in parallel with whatever residual resistance exists in the contact increasing the passage of AC signals. Given sufficient DC bias within the gaps of the contact the thin film of Stabilant will "switch", conducting by quantum tunnelling, and thus limit the resistance of the contact to a serviceable level.
What is the 15 ml service kit?
This was made up at the request of several manufacturers who wanted a standard kit that they could issue to their service personnel. It consists of a 15 ml dropper bottle of Stabilant 22A and some applicators, all in a small capped cardboard tube that can be tossed into a tool box without damage. As noted, we can provide these kits with special labels when large volume orders are involved.
Why would anyone want to buy large quantities of the concentrate?
Many manufacturers make large volume purchases, diluting the material for specific applicators used on their production lines.

Many end users have found that the material cuts their service costs so much that is more economical to purchase Stabilant 22 in the larger container sizes rather than run any risk of being without the material. The number of uses tends to increase users discover the large number of problems that can be solved by the material. One user routinely applies it to the flashlight switches and batteries it issues to its security guards and has reported that the number of requests for replacement units has dropped appreciably.

How can I be sure that Stabilant works?
The best way to find out just how well it works is to try it out; that's why we have samples available. Almost every service shop or manufacturer has equipment available where the switches or connectors have become erratic over the years. Use Stabilant 22/22A/22E on them and satisfy yourself. A word of caution. Don't try to evaluate Stabilant 22's performance on brand new connectors. Instead, use it on connectors that are corroded, or dirty or just plain unreliable. We are sure that any organization dealing with electronics will have at least one piece of unreliable equipment on which the Stabilants can be tested!
Will it work on UHF equipment?
Stabilant 22 is being used at satellite communication frequencies on waveguide flanges up to 5 gHz and co-ax connectors as well, so yes, it will operate on UHF equipment and at UHF frequencies.
Can I use Stabilant 22 on connectors and switches in other equipment?
Of course. As we indicated, many end-users start out by trying it out on erratic test equipment. Audio/RF Function and Signal generators, distortion, spectrum. and waveform analyzers, reflectance equipment, Oscilloscopes, Vector Scopes; all types of test gear can be made more reliable using the material. One note of caution though; because Stabilant 22/22A/22E switches to the conductive state under applied electric field gradients (in the open) of from 9,000 to 13,000 volts per inch, don't use it on high voltage connectors. As a rule-of-thumb, it can be used on circuits of under 100 volts with impunity. Where higher voltages are involved it may be necessary to calculate the electric field gradient across the insulating surface to determine if the material can be used. If however, the material can be applied ONLY to the contacts, and no excess is used, it can be used at much higher voltages.

When used on socketed IC's, photo-couplers/isolators, rotary, push button (such as the ITT Schadow # FE switch), or slide switches, or even on BNC connectors, the net effect is usually to make the proper operation of the equipment less erratic, and in the case of IEEE-488 bus-controlled equipment, to cut down on the potential for system lock-ups. The effect of Stabilant 22 in Computers is to reduce the number of times the system locks-up or crashes, sometimes it even eliminates non-software crashes completely. On equipment using internal microprocessor control, Stabilant 22/22A/22E has an obvious use on socketed IC's, card-edge connectors, and both parallel (Centronics Standard) and Serial (RS-232C etc.) Ports.

Is Stabilant hazardous to use?
Stabilants have very low oral toxicity. Under normal workplace conditions no skin sensitization effects have been noted. In the undiluted form, it is non-flammable although if heated above 200° Celsius the decomposition products would burn. And Stabilants are environmentally friendly materials.
What is the best way to apply Stabilant to a contact?
The 15 ml (and the 50 ml) container have "controlled-dropper" type caps that allows Stabilant 22A to be applied directly to such components as socketed IC's, switches, connectors, etc. Some end users prefer to use industrial syrettes to apply the material. Camel's hair brushes can be used to brush it on card-edge connectors or they could be dipped into the dilute material. Most metering type liquid dispensing systems can be used as well.
Does the action of Stabilant deteriorate with age?
In some field trial applications lasting over fifteen years Stabilant 22 has shown no sign of reduced effectiveness. With a high molecular weight and a very low vapor pressure, little is lost by evaporation. Unlike some other contact protection oils, Stabilant 22 will not cross-link when exposed to free machining materials such as high sulfur brass, or when used on contacts where agents used to promote cross linking of thermosets or elastomers are present in the environment or in the actual connector components. Unlike non-saturated oils, Stabilant 22 does not "varnish".

Revision 4

Stabilants™ are a product of Dayton Wright research & development and are made in Canada

NATO Supply Code 38948
15 ml of S22A has NATO Part # 5999-21-900-6937