Traffic signal

[roadfro]

This example on Reservation Road in Marina, California is a good example of a signal-pole style in California during, I think, the 1960s.  There are still a lot of these within Monterey County, such as this one.

https://goo.gl/maps/fCUxFDTqvXhqoBrEA

I do believe there are still several examples in the greater Sacramento area. At least that's where I recall seeing this style first.

That mast arm curve to display the left turn signals lower is really unique, but I gotta wonder why they did that in the first place... Perhaps these are replacements for what may have been post-mounted signals in the narrow median, and they did this to avoid knockdowns. Most of these that I've seen do appear that the curved portion of the arm was added on later. I've also only seen this style where the turn signal is above a (often narrow) median island.

[SkyPesos]

I'm looking at some Phoenix SPUIs from the discussion from a week ago, and found a straight movement red light with an up arrow. This is common in some other countries, like China, but it's the first time seeing one in the states for me. Any other examples of this?

[jakeroot]

That mast arm curve to display the left turn signals lower is really unique, but I gotta wonder why they did that in the first place... Perhaps these are replacements for what may have been post-mounted signals in the narrow median, and they did this to avoid knockdowns. Most of these that I've seen do appear that the curved portion of the arm was added on later. I've also only seen this style where the turn signal is above a (often narrow) median island.

Best I can assume is that they wanted the left turn signal to be lower than the through signals, as it was common for years to have the left turn signal at pole-mounted height rather than overhead.

In BC, it's normally taught that overhead signals are for through traffic, and when there is a protected left, the median signal is the one you look for. BC still calls for median-mounted pole-level left turn signals when possible, otherwise they are placed overhead.

In short: those curved signals in California may have been trying to get the left-turn signal to pole-mounted height over the median, without actually pole-mounting the signal (to avoid knockdowns I guess).

[jakeroot]

I'm looking at some Phoenix SPUIs from the discussion from a week ago, and found a straight movement red light with an up arrow. This is common in some other countries, like China, but it's the first time seeing one in the states for me. Any other examples of this?

I don't believe it's allowed, but it's seen most often in states where all-arrow signals are normally common. Example near me.

[Caps81943]

whatever this is in El Reno.

Nice map of El Reno.  What were you trying to show us?

Sorry about that, something happened with the link.  Here it is.

[US 89]

whatever this is in El Reno.

Nice map of El Reno.  What were you trying to show us?

That first link worked for me...

[Caps81943]

whatever this is in El Reno.

Nice map of El Reno.  What were you trying to show us?

That first link worked for me...

Yeah, I edited the first link after the fact.

[roadfro]

I'm looking at some Phoenix SPUIs from the discussion from a week ago, and found a straight movement red light with an up arrow. This is common in some other countries, like China, but it's the first time seeing one in the states for me. Any other examples of this?

I don't believe it's allowed, but it's seen most often in states where all-arrow signals are normally common. Example near me.

Yeah, straight ahead red arrows are not allowed in the MUTCD. That's one thing I've never really understood the rationale for.

Despite this, I have occasionally seen them in practice here in Nevada. Usually, it's somewhat of a reinforcement of a turn prohibition where you might more commonly see a green straight  arrow, such as this no left turn into a bus station in Sparks. But the main use seems to be the crossover points at DDIs, like every through signal at I-580/US 395 & Moana Ln in Reno or I-11/US 93/US 95 & Horizon Dr in Henderson.

[DrSmith]

I'm looking at some Phoenix SPUIs from the discussion from a week ago, and found a straight movement red light with an up arrow. This is common in some other countries, like China, but it's the first time seeing one in the states for me. Any other examples of this?

I don't believe it's allowed, but it's seen most often in states where all-arrow signals are normally common. Example near me.

Yeah, straight ahead red arrows are not allowed in the MUTCD. That's one thing I've never really understood the rationale for.

Despite this, I have occasionally seen them in practice here in Nevada. Usually, it's somewhat of a reinforcement of a turn prohibition where you might more commonly see a green straight  arrow, such as this no left turn into a bus station in Sparks. But the main use seems to be the crossover points at DDIs, like every through signal at I-580/US 395 & Moana Ln in Reno or I-11/US 93/US 95 & Horizon Dr in Henderson.

A red up-arrow. It used to be a 3M signal and was replaced with this one. The green arrow is louvered to block the sight line unless you are right up on it. When this one is red, so are the other signals through there. Maybe the red up-arrow is to try and highlight the no left turn here.
https://goo.gl/maps/mrAC5KFW9a93pG9i6

[mrsman]

I'm looking at some Phoenix SPUIs from the discussion from a week ago, and found a straight movement red light with an up arrow. This is common in some other countries, like China, but it's the first time seeing one in the states for me. Any other examples of this?

The straight red arrow is disallowed because a red ball would be easier to see than a red arrow.

What's also interesting about this signal is that it is also a bus signal.  Apparently, buses along SR-51 are encouraged to exit and then continue back on the freeway.  I guess they feel it is quicker for buses to do that in heavy traffic periods.  What's interesting is that there is no provision for that in the other direction.  What is also interesting is that there is no bus stop at that point.  In LA, freewaay buses that exit usually do so to service an exit.  Here is an example of a freeway bus along US 101 that exits at Van Nuys Blvd at a diamond interchange, continues straight across the street and then makes a stop just before the on-ramp.

Bus stop shown, not the bus itself.

https://www.google.com/maps/@34.1562833,-118.4478097,3a,37.5y,141.57h,87.25t/data=!3m6!1e1!3m4!1sEWnqDJvSWCYtNAVATFqFtw!2e0!7i16384!8i8192

[Caps81943]

What are the square things on the back of these signals near Birmingham? My initial guess was something to make the light not very visible from far away, but streetview says otherwise. For what it's worth, the far lights on the road's other side also have these.

[PurdueBill]

What are the square things on the back of these signals near Birmingham? My initial guess was something to make the light not very visible from far away, but streetview says otherwise. For what it's worth, the far lights on the road's other side also have these.

Federal Way, WA installed quite a few of these for a while, although they used them at several intersections where I'm not sure it was necessary to limit the visibility of the signals.

All of their uses were flashing yellow arrows. Here's an image I took today. Note that tunnel visors are used, instead of the cutaway visors seen on all of the previous examples. Cutaway visors are very rare here in Washington, generally being used on signals with limited visibility features (except for these, obviously).

Looks like heat sinks for the ESB PV signals discussed in this old thread.

[roadfro]

I'm looking at some Phoenix SPUIs from the discussion from a week ago, and found a straight movement red light with an up arrow. This is common in some other countries, like China, but it's the first time seeing one in the states for me. Any other examples of this?

What's also interesting about this signal is that it is also a bus signal.  Apparently, buses along SR-51 are encouraged to exit and then continue back on the freeway.  I guess they feel it is quicker for buses to do that in heavy traffic periods.  What's interesting is that there is no provision for that in the other direction.  What is also interesting is that there is no bus stop at that point.

The Phoenix signal appears specifically accommodates bus access to a Park & Ride. If you follow the street view across Shea Blvd across to the on ramp, you'll see there's a slip ramp marked for buses only. This services a park & ride facility (with nearly all covered spaces!). There is another access so that buses can come back down from the park & ride to merge back to the same on ramp. Here's a Google Map for an overview.

[roadman65]

https://goo.gl/maps/uM7BofJqhQuGw6T48
Instead of a doghouse.

Yeah I know many 8-8-8 have them but on 12-12-12 is common, but not as though interesting.

[jakeroot]

https://goo.gl/maps/uM7BofJqhQuGw6T48
Instead of a doghouse.

Yeah I know many 8-8-8 have them but on 12-12-12 is common, but not as though interesting.

That's just a regular side-by-side 5-section signal. Not common apart from Colorado, West Virginia, and parts of New York and Maryland.

I personally prefer this style, but that's neither here nor there.

[SignBridge]

The side-by-side configuration dominates on Long Island in both NYS DOT Region-10 and Nassau County DPW installations. Not sure what Suffolk County does.

Like Jakeroot, I also much prefer it to the doghouse. 

[jakeroot]

Not sure what Suffolk County does.

Very brief tour on Street View would suggest that side-by-side is also dominant there. Very new example.

edit: that may not be a county install; disregard if so.

[traffic light guy]

The side-by-side configuration dominates on Long Island in both NYS DOT Region-10 and Nassau County DPW installations. Not sure what Suffolk County does.

Like Jakeroot, I also much prefer it to the doghouse.

They're called offset doghouses

[jakeroot]

The side-by-side configuration dominates on Long Island in both NYS DOT Region-10 and Nassau County DPW installations. Not sure what Suffolk County does.

Like Jakeroot, I also much prefer it to the doghouse.

They're called offset doghouses

Well, in addition to, but I've never heard that as the official term. Both are widely used, although I've seen "side by side" used more.

[tolbs17]

What's with the double red lights here in NC? Does it mean to stop only by looking at 2 red lights?

[jakeroot]

What's with the double red lights here in NC? Does it mean to stop only by looking at 2 red lights?

Double reds are an option that some states use more than others (Texas in particular). It has no special meaning.

[Dirt Roads]

What's with the double red lights here in NC? Does it mean to stop only by looking at 2 red lights?

Double reds are an option that some states use more than others (Texas in particular). It has no special meaning.

How about redundancy?  The purpose of color position lights (CPLs) on certain railroads was to provide for redundant aspects.  Otherwise, the FRA requires "light out protection" for any signal where a burnt out light bulb could be misconstrued as an increase in signal indication.  I've seen some folks run traffic signals when the light bulb is burnt out because it resembles a power outage (and they thought they were on the "priority" route).  That's why the law requires a "four-way" stop when the signal is not working.  (Not really an all-way stop when a bulb is burnt out).

[roadman65]

What's with the double red lights here in NC? Does it mean to stop only by looking at 2 red lights?

Double reds are an option that some states use more than others (Texas in particular). It has no special meaning.

j

San Antonio don't use double red signals.

[jakeroot]

What's with the double red lights here in NC? Does it mean to stop only by looking at 2 red lights?

Double reds are an option that some states use more than others (Texas in particular). It has no special meaning.

San Antonio don't use double red signals.

A lot of Texas doesn't, but the number of double reds in other parts likely outnumbers the total number in most other states put together. I can think of two or three double reds in all of Washington.

How about redundancy?  The purpose of color position lights (CPLs) on certain railroads was to provide for redundant aspects.  Otherwise, the FRA requires "light out protection" for any signal where a burnt out light bulb could be misconstrued as an increase in signal indication.  I've seen some folks run traffic signals when the light bulb is burnt out because it resembles a power outage (and they thought they were on the "priority" route).  That's why the law requires a "four-way" stop when the signal is not working.  (Not really an all-way stop when a bulb is burnt out).

I'm more in favor of positional redundancy. Cramming signals overhead meets MUTCD requirements, but they're easily blocked. It's better to have multiple signals than repeated displays on the same head, in my opinion.

[SkyPesos]

https://goo.gl/maps/uM7BofJqhQuGw6T48
Instead of a doghouse.

Yeah I know many 8-8-8 have them but on 12-12-12 is common, but not as though interesting.

That's just a regular side-by-side 5-section signal. Not common apart from Colorado, West Virginia, and parts of New York and Maryland.

I personally prefer this style, but that's neither here nor there.

I'm still a traditional doghouse fan, because of the symmetry.

Also there's this doghouse variant (idk the actual name of it) with a missing yellow left signal that I sometimes see in Columbus. Not sure how it works; does the yellow left arrow share the same section as the yellow ball?