Okay, let’s stay on topic. We should be talking about obscure (not known to human) 4903s such as units like 4903-9136 & 4903-9145 which are essentially different variants of/like the 4903-9147
Here’s a list of obscure 4903 models I know so far
4903-9136 - 24 Flashes Per Minute, 15CD, 25VRMS Speaker, Red Vertical
4903-9145 - 60 Flashes Per Minute, 110CD, 25VRMS Speaker, Red Vertical
4903-9109 - 24 Flashes Per Minute, 110CD, 70VRMS Speaker, Red Horizontal
Related not obscure models include 4903-9107, 4903-9144, 4903-9147 & 4903-9174
It makes a lot of sense that the 4903-9145 is a red vertical mounted 110CD 25VRMS Speaker/Strobe since they obviously have 4903-9142 (30CD), 4903-9144 (110CD), 4903-9146 (15CD) & 4903-9147 (15CD). 4903-9145 is right in between 9144 & 9146 and since 9145 & 9147 are odd numbers that means they are vertical mounted while even numbers are horizontal mounted. Now since I see the pattern, they probably have had to make a 4903-9143 Speaker/Strobe, a red vertical mounted 30CD Speaker/Strobe. I feel like 70VRMS vertical mounted speaker/strobes would be in the 4903-917X series. As of now, they’re obscure.
Most of the 4903-91XX speakers have completely Free Run strobes
I wonder if we’d be able to figure out any other speaker visibles & horn visibles