The earliest sets of mast-arms you can remember

[traffic light guy]

Trenton: During the mid-to-late 1960s, older signal heads on trombone arms, usually 8-inch

Atlantic Coastline Cities: 60s, with Marbelites on trombone mast-arms.

Pittsburgh: Marbelite signals on guy-wires, mid-60s.

Harrisburg: During the 1970s, with 12-inch Eagle flatbacks on angled mast-arms

Montgomery/Bucks/Delaware/Chester Counties in PA: 1960s/70s with 12" Eagle flatback installs, on either angled or straight mast-arms.

Philadelphia: In Summer 1975, on the entirety of Broad Street, mast-arms were being installed. These included Eagles, Econolite Bullseyes, and Crouse-Hinds signal heads. The earliest use for Philly was 1974. As of this post, some of the Summer 1975 installs are still serving, on the northernmost tip of Broad Street. Even though Philly didnt start until 1974, the rest of PA adopted the use of mast-arms a mere five to seven years earlier than Philly.

[epzik8]

Possibly along Route 24 in the Bel Air, Maryland area from the late '80s/early '90s.

[roadman]

First mast arms I remember seeing being installed were on Elm Street in Manchester, NH in the late 1960s.

[PHLBOS]

For my hometown of Marblehead, MA; it would be the original (pre-1980) signal set-up at the intersection of MA 114 (Lafayette St.) & West Shore Drive that contained 12-8-8 signalheads.  Those were likely erected sometime during the late 50s/early 60s.  The original mast-arm was located in front of current mast-arm assembly almost adjacent to the crosswalk; note: the signal post in front of it is the only signal in that intersection which still utilized the older signal base (all the other signals had newer (1980-vintage) signal bases. 

For the oldest mast-arm signal still standing today; it would be this one along MA 129 (Atlantic Ave.) & Clifton Ave.; this one was erected during the very early 70s (1970 or 1971).  Yes, those are the original signalheads (mast-arm-mounted assemblies only); which were originally green where they're now painted yellow.

Such was also the first use of 12-12-12 signalheads in that town as well.

[JJBers]

Tuckie Rd. and US 6
Sometime around 2009.

[roadman65]

Many NJ signals used double guys with a bracket especially Morristown. They changed them out in the mid  1980s. I believe a couple are still left. But in the early 70s the US 202 & Sussex Avenue were the only truss style mast arms in the town pretty much.

[jakeroot]

I'm going to look at this from a 'last span wire signal installed' perspective...

Pierce County, WA is the only agency near me that still installs span-wire (all others have been using mast arms for quite a long time), but it's only on a limited, cheapo temp-signal basis. Never anything permanent anymore. The last non-temporary span wire signal was installed at 160 Street and Woodland Ave in 2009 2014.

AFAIK, the first mast arm installation was in 2001 along Canyon Road (SE of Tacoma) between the WA-512 ramps and 116 Street. It was part of a six-laning project by the County, which was a first for them, so it makes sense that they'd go the extra distance and install mast arms.

[traffic light guy]

These are the earliest examples of mast-arms, that are found in the Philadelphia area:


This is across the street from the cheltenham shopping center, the oldest equipment in this intersection dates back to the 1960s:

Next, is one of my favorites, I smile everytime I pass this setup. We have a set of awesome old kick-ass 12-inch Eagle flatbacks on angled mast-arms! The install time for these was Summer 1969:









These are on the border between Abington and Upper Dublin Townships, at the intersection of North Hills Avenue and Fitzwatertown Road.

Unfortunately, PennDOT is setting up bids in order to replace these, which really pisses me off.

[roadman65]

Does PA still have the red ball on 24/7 as in the photo?  I always remembered the left turn signals in many places the red signal always stayed on when the protected arrow was given and that photo there brought back the memories.

[traffic light guy]

Does PA still have the red ball on 24/7 as in the photo?  I always remembered the left turn signals in many places the red signal always stayed on when the protected arrow was given and that photo there brought back the memories.

The signal in the photo is still serving, unfortunately there's very few of those left. Philly also has a 24/7 red ball:
I couldn't get a shot of the left turn signal while the arrow was on. It does have a 24/7 red ball, although it's not lit when the yellow is on. The yellow is stand-alone

[thenetwork]

My first was an intersection of custom-made mast arms likely installed in the 60s at the intersection of West Market St. & Ghent Rd. in the Akron, Ohio suburb of Fairlawn, by Summit Mall. 

I say custom made since I've never seen another set like them -- dark green masts that arched over the lanes.  They were replaced in the early 90s.
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