The Poles Inc era, my personal favorite era, and the last era that had classic signal brands. In Pennsylvania, this is the most important and revolutionary era, due to the fact that many important signal designs that we have today were introduced during this time period. This is the transitional phase in Pennsylvania’s traffic signal history, the final era to use classic old timely signal brands, but the first to have modern configurations, such as modern monotube mast-arms, pedestrian signals, protected left turn signals, and doghouses. This era began in the mid-1960s, and ended around 1977, when the TE-7800 standards were issued, and Pennsylvania switched from using the Poles Inc mast-arms, to the more common type of mast-arm that you would see today. There were very few installations in the early-80’s that used poles inc specs, but they were new old stock, and very few and far between, and rare. The most common type of mounting used in this time period would be the horizontal Poles Inc mast-arm, with “stackable” pieces that had a trapezoid flange in the end. The most common type of signal brands used in this time period were Eagles, which dominated Philadelphia and it’s suburbs, while western Pennsylvania had square-door Econolite Bull’s eyes on span-wires. Although most of Eastern Pennsylvania was Eagle at the time, the city of Philadelphia had a mix of several different brands at time time, which included Econolite Bullseye, Marbelite, Highway Signal & Sign Co., and Crouse-Hinds. Philadelphia didn’t use mast-arms until the TOPICS project kicked in, with funding beginning as early as 1972, and having been complete in 1976. The rest of the suburbs began using mast-arms earlier, the earliest known mast-arm install was a set of 12-inch Eagle Flatbacks mounted on Easton Road mounted by the Ceaderbrook Shopping Center in Cheltenham, which had an inspection letter dating from 1965. Earlier Poles Inc installations had the diagonal mast-arms, and many SE PA signal enthusiasts refer to them as “angled mast-arms”, while later Poles Inc era installs (usually the ones dating from the 70s), had the straight factory assembled “stackable” mast-arms, that had the trapezoid shaped flanges. These poles, although long lasting, and possibly durable, they were very prone to rusting. This was around the time where traffic density was increasing in the state, and the need for protected left turns was needed, in this time period, 3M signals were usually used for protected left turns.
Here’s a photo showing the 1960s/70s era Poles Inc mast-arm. Later factory assembled Poles Inc mast-arm, used from 1970 to 1977, included with stackable pieces, assembled in Pennsylvania, and includes a trapezoid shaped flange.
Poles Inc era specs
An installation in this time period would consist with a set of 12-inch Eagle flatbacks on straight mast-arms with a trapezoid shaped flanges. The signals had ring-shaped astro-bracs, and sometimes louvered backplates. Earlier Poles Inc installed, had signal hanging from the mast-arm by a gooseneck hanger, hanging from an angled mast-arm. The controller would usually be a mechinal Eagle signal cabinet. If it wasn’t a set of Eagle flatbacks installed during the Poles Inc era, there would usually be a set of 12″ Crouse-Hinds type R signals. Pedestrian signals would be Eagles as well, but a majority of the time, an 8″ vehicular signal would be used for pedestrians. Philadelphia would have new-old-stock signal heads during this time period, 12″ Crouse-Hinds type Ms, especially. As for the Eagle flatbacks, although the Durasig was introduced in 1969, and was launched in 1971, with the flatback design being discontinued in 1973, Pennsylvania held on to them for as long as possible, being installed as late as 1976. If you were driving through southeast Pennsylvania in the 70’s, you would see almost nothing but Eagle flatbacks on angled mast-arms.
Pennsylvania’s first Doghouses
The doghouse design was approved by the MUTCD in 1971, and Pennsylvania started using them shortly after. A few early-70s doghouses are still in service to today. One mounted at Conshohocken State Road at Rock Hill Road in Bala Cynwd, another mounted at Levering Mill Road and Belmont Avenue in Bala Cynwd, and a third one mounted at Mill Creek Road and Edgely Road in Levittown, PA. There were formally a set of 12″ Eagle flatback doghouses installed at the intersection of Bristol Oxford Valley Road, Bath Road, and Lakeland Avenue in Bristol Township, PA. Although, those signals were removed, a few SE PA signal fans (including myself were able to document this land mark. The 12″ Eagle flatback doghouses at the intersection of Bristol Oxford Valley Road, Lakeland Avenue, and Bath Road were installed in the mid-1970s, and were in service until 2018, when the Green Light Go Program executed them, and replaced them with typical garden variety 12″ McCains. Doghouses were extremely uncommon during the Poles Inc era, at the time most left turn signals were four sections or 3Ms.