IIRC, Westie always had the OV-15 PC in the back, while the OV-25s PC kept getting pushed back more and more. The OV-50 always had it in the front under westinghouse. Sort of ironic how Crouse-Hinds moved the PC on the OV-15 and OV-25 up to the front, but the OV-50 PC was moved to the back. Now the OVL has it in the origional position.

I've actually only seen the OV 25 with back mounted PC only a few times here. Most here are the so called Canadian 4th gen design.

Most of them here are the late 60's version with the PC mounted at about the position of the NEMA tag on this one.

There's not a lot of 60s medium fixtures left here, I think a few Unistyle 400s, a handful of M400s, OV 25s and B2215s and I think that's it. The 70s and Cooperized versions outnumber the 60s ones here.

Not many older fixtures here either. The M-250R2 is the most commonly found fixture around here.

My neighbourhood is a bit older so you'll see a lot of Westys and Powerlites hanging around but most newer places use AEL 125s, 115s (probably most common) and Cooper OVFs.

My street is from the 70s and some of the other roads are from the 70s too, but most of the houses like mine are from the 90s-present. The streets near me with the mercury vapor M-250A2 FCO are actually newer than the roads with HPS. The tapered E arms seem to be the oldest. Then cantilever. NGrid uses upsweep. All the arms are six feet in length though.

Heh, my street was developed in 1982 when my house was built and used Westy OV 15s...probably one of the last made. The other streets in my neighbourhood are from the mid-late 70s and used McGraw Unidor 150s and Powerlite B2227s. The poles are all 30ft tall concrete with 8 foot tapered e arms.

My neighborhood was developed in the early 1900's, the old street lights in my neighborhood were McGraw Edison Unistyle 175's which were over 40 years old when they were replaced with high pressure sodium streetlights in 2008, sadly there's only a few left.

@ Alex, where there any lights before the unistyles? My street probably had bail latch MV M-250R or possibly OV-15, as they were used, but to a lesser extend than the GEs. With medium fixtures it seemed to be pretty 50/50 between GE and Westie be looking at pictures, though GE more M-400s are left today than OV-25. The cantilever arms on my street were most likely added when the neighborhood built up some and probably held FCO 100W MV M-250A2.

For my electrical company in my area for 60s medium Cobraheads, it seems the Line Materials 400 and OV-25 has been hit hard, because before the Baltimore City area had a LOT of Line Materials and OV-25s, but those were pretty much wiped out around the late 70s, plus the reason there are not much of those LM 400 and OV-25s is because in favor of the GE M-400A powerdoors....they did use Tudors OV-25s and McGraw-Edison Unidor 400s but the Unidor 400 seems more common in HPS and the GE M-400A was more common using MV. But throughout those times it seems the small sized powerdoors were only common for HPS only, but was dropped around the mid 80s and only large fixtures in HPS and MH are used with powerdoor fixtures today while before the MV ban, the 400 watt one door was used since mid 80s and one door for all small fixtures since mid 80s too...

In the early-to-mid 70s, 400W MV M-400 split door were used. In the mid-to-late 70s, 250 and 400W HPS M-400 split door were used. Then they switched to 250W HPS M-250R2 when they did the huge MV wipeout on main roads in the 90s.

Westinghouse OV-15 and OV-25's were the most popular mercury vapor street lights in the late 60's and late 70's. In the early 80's, the L-150 and L-250 high pressure sodium streetlights were installed on the PA Turnpike and were also installed in Duquesne Light's area, the mercury vapor L-250's were very rare in their service area and no longer exist as of January 2010. West Penn Power never bought L-250's but they installed mercury vapor L-150's in the late 70's and early 80's. Duquesne Light installed mercury vapor replacements until early 2006, Allegheny Power continued installing mercury vapor replacements until mid 2008.