There were multiple varieties, but all are belt drive systems with copper contact discs and power brushes protruding down from the bottom of the rotators. The contact plates were divided into sections. When different sections were deenergized the bulbs would go out. The motor would be started and stopped by what the contacts were touching from what I remember too. I may be wrong but I do not recall any feature that didn't somehow use the contact discs in some way.
I had the brush and plate system backwards. The plates are often on the rotator, the brushes on the frame. Same idea. They can act as triggers or be triggered for both light and motor function. As stated, the system was cool but often prone to failure and/or underused and thus disabled.
As John said!
The bars were prepared for this. To use this option you only needed the (more expensive) deluxe controller.
That "controller" looks exactly like the one that was posted years ago, lol (clamping wires to wires). You can actually make a home brew deluxe controller with standard switches and momentary switches. How..... I am not 100% sure. I know one of the deluxe controllers had a switch for activation of select alert, a switch for night probe, and a momentary button to "jog" the lights forwards and backwards. I want to say some systems used double throw momentary switches to jog the system forwards and backwards instead of two push button momentary switches.As John said!
An important detail of the Nightprobe are the built-in diodes. These separate or connect the different sections/contacts depending on the applied potential (ground and +12V in different combinations).
The bars were prepared for this. To use this option you only needed the (more expensive) deluxe controller.
Unfortunately I couldn't find a NightProbe controller yet - so I'll probably have to build one. Then of course with the deluxe option.
At the moment my controller looks like this:
View attachment 243745
As far as I know, the basic controller had a 3-position (0-1-2) main switch for selectalert and full 360° warning (Beacon) and per side a double row 2-positon switch for activation the NightProbe Option.
Yes, these diodes work and in the later SD and XL bars they were also used that way, but in the early SD bar they used a different type/design.
I'm in the process of creating one!
Mine was not marked. I bought it from Streicher's in Milwaukee c.1987 ... anyone that knows the place might remember Fred. He sold it to me on the 30/30 Warranty: 30 feet or 30 seconds, whichever comes first. No idea where it came from.
Yes, that's one of those relays I meant!
Three? I only know these two:
I remember seeing a older style with a round top, just like the bottom portion (not individual tabs) . I Might be an incorrect memory or homemade fix. The two you posted are the two official sealed beam styles, I just thought there was another variation on the round base style.
Ok, so Mandela effect maybe? I was very sure there was a version of the round base style with a round top of the same diameter (not tabs sticking off) where you had to loosen the whole top. I can't find any pictures so I guess it is a false memory. Two rotator types seems to be the correct info.
I got the basic wiring diagram of the Nightprobe option from the patent. Then I added the Select-Alert rotators into the schematic.
In Canada, the Code 3 SD light bars were imported by Dominion Auto. I saw a few of them on fire engines and tow trucks.
