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This pole supports a separate fiber optic cable in the communications space. Depending on purpose and age, these circuits may utilize open-wire conductors, twisted-pair cables (similar to telephone networks), coaxial cables (similar to CATV networks), or fiber optic cables. The strand is placed under tension to prevent excessive sag; typical strand tension is a few hundred pounds, although a strand supporting a large multipair cable may be tensioned as high as 1000 pounds. Each telephone cable contains several individual copper wire pairs; a large cable may contain as many as several hundred pair. Secondary distribution conductors are usually twisted together in a bundle called duplex (two conductors), triplex (three conductors), or quadruplex (four conductors), although older secondary distribution circuits may consist of separate open wire conductors. The secondary distribution wiring appears to be a duplex bundle in which the MGN serves as both neutral and mechanical supporting strand. Secondary distribution. - CATV cables. Telephone and other communications cables are supported in the same manner. The Safety Zone Space is an unused space separating electric supply facilities from communications facilities.

This space is specified by the National Electrical Safety Code to separate electric supply conductors from communications conductors. The Communications Space contains telephone, cable television (CATV), and other communications cables. Typical communications cables include: Telephone: telephone cables supported by steel strand. Items on this pole include: Strand. This pole supports an enormous transmission line, probably at least 69-Kv, possibly even higher. To receive digital cable channels on an analog television set, even unencrypted ones, requires a different type of box, a digital television adapter supplied by the cable company or purchased by the subscriber. The I-Net is physically identical to the public CATV network (and, in fact, it was built by, and is probably still owned by, the CATV company). CATV cable for public cable TV network. Cable TV: CATV coaxial cable and equipment supported by steel strand. The CATV network is offset on a sidearm probably to maintain clearances from other facilities. Bases on the continent itself are able to communicate with one another via radio, but this is only a local network. These amplifiers require operating power; this power (at 60, 75, or 90 volts RMS) is provided by a CATV power supply similar to the one shown here, and delivered to the amplifiers over the CATV network itself.

Most stepdown transformers are designed for single-phase operation; if a three-phase secondary circuit is required, three physical transformers are usually required, and may be mounted the same pole as shown in the photo above. The separations shown in this diagram are typical, although there are numerous exceptions and special cases. The riser conductors are usually protected by conduit, although a U-guard is sometimes used. High-voltage overhead conductors are not covered by insulation. The currents in the three phases of the transmission (or sub-transmission) line are never quite equal; if they are wye-connected, the MGN carries the residual unbalance current. At many poles, the MGN is physically grounded to a groundrod at the base of the pole. When the shaft is depressed the current goes to the white bulb dirrectly which is well grounded. Secondary Distribution: one or more insulated conductors, accompanied by an uninsulated grounded neutral conductor (which may be the MGN). One open-wire secondary distribution circuit.

Seasonal decorations often contain lighting circuits; these circuits are usually fed from the secondary distribution circuits on the pole. This particular concrete pole supports: - Static wire. This pole supports: - Three-phase open-wire primary electric distribution. This pole supports: - Three-phase primary electric distribution. It's a cable-only pole. No real-world joint pole looks exactly like the archetypical pole defined above, but some come pretty close. Note that the fire-alarm wiring is open wire, and that it appears to be very close to the CATV cable. A static wire. - A large transmission line, probably at least 69-Kv. - Secondary distribution wiring (both open-wire and triplex). The pole includes an unmetered streetlight, wired directly to the secondary. A streetlight, hardwired directly to secondary distribution. A streetlight. - A single-phase secondary distribution circuit (fed from a transformer offscreen to the right) whose sole purpose is to provide power for the streetlight. Primary Distribution: one to four uninsulated conductors, frequently supported on a crossarm, which carry power from substations to pole-mounted stepdown transformers. Prestressed concrete poles are often used in coastal areas subject to atmospheric corrosion (one manufacturer claims that "concrete poles are foremost in appearance, durability and maintenance-free service").

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