high voltage circuits and terminals, with interlock switch-

es to open primary circuits of the power supply and to

discharge high voltage capacitors whenever access doors

are opened. Interlock switches must not be bypassed or

“cheated” to allow operation with access doors open.

Always remember that HIGH VOLTAGE CAN KILL.

RADIO-FREQUENCY RADIATION - Avoid exposure to

strong rf fields even at relatively low frequency. Ab-

sorption of rf energy by human tissue is dependent on

frequency. Under 300 MHz most of the energy will pass

completely through the human body with little attenuation

or heating effect. Public health agencies are concerned

with the hazard, and the published OSHA (Occupational

Safety and Health Administration) or other local recom-

mendations to limit prolonged exposure of rf radiation

should be followed.

INTERELECTRODE CAPACITANCE - The actual internal

electrode capacitance of a tube is influenced by many

variables in most applications, such as stray capacitance

to the chassis, capacitance added by the socket used,

stray capacitance between tube terminals and wiring

effects. To control the actual capacitance values within

the tubes, as the key component involved, the industry

and Military Services use a standard test procedure as

described in Electronic Industries Association Standard

RS-191. This requires the use of specially constructed test

fixtures which effectively shield all external tube leads

from each other and eliminates any capacitance reading to

“ground.” The test is performed on a cold tube. Other fac-

tors being equal, controlling internal tube capacitance in

this way normally assures good interchangeability of tubes

over a period of time, even when the tube may be made by

different manufacturers.

The capacitance values shown in the manufacturer’s

technical data, or test specifications, normally are taken in

accordance with Standard RS-191.

The equipment designer is therefore cautioned to make al-

lowance for the actual capacitance values which will exist

in any normal application. Measurements should be taken

with the socket and mounting which represent approxi-

mate final layout if capacitance values are highly signifi-

cant in the design.

SPECIAL APPLICATIONS - When it is desired to oper-

ate this tube under conditions widely different from those

listed here, write to CPI MPP, Eimac Operation, Applica-

tions Engineering, 607 Hansen Way, Palo Alto, CA 94304

U.S.A.

4cx25,000c

OPERATING HAZARDS

Proper use and safe operating practices with respect to power tubes are the responsibility of equipment manufacturers and users

of such tubes. All persons who work with and are exposed to power tubes, or equipment that utilizes such tubes, must take precau-

tions to protect themselves against possible serious bodily injury. DO NOT BE CARELESS AROUND SUCH PRODUCTS.

The operation of this tube may involve the following hazards, any one of which, in the absence of safe operating practices and pre-

cautions, could result in serious harm to personnel.

HIGH VOLTAGE – Normal operating voltages can be deadly.

Remember that HIGH VOLTAGE CAN KILL.

LOW-VOLTAGE HIGH-CURRENT CIRCUITS - Personal jewelry,

such as rings, should not be worn when working with filament

contacts or connectors as a short circuit can produce very high

current and melting, resulting in severe burns.

RF RADIATION – Exposure to strong rf fields should be avoided,

even at relatively low frequencies. CARDIAC PACEMAKERS

MAY BE AFFECTED.

HOT SURFACES – Surfaces of tubes can reach temperatures

of several hundred°C and cause serious burns if touched for

several minutes after all power is removed.

MATERIAL COMPLIANCE - This product and package conforms

to the conditions and limitations specified in 49CFR 173.424 for

radioactive material, excepted package-instruments or articles,

UN2910. In addition, this product and package contains no

beryllium oxide (BeO).

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