Can Anyone Identify This Trap?

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I'm thinking it could be a notch filter rather than a band trap?

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It certainly looks like a notch filter. Notch filters fell from grace maybe 35-40 years ago.
But the question is what channel(s) does it filter?

I'm guessing it would be used by a hotel or hospital to mix the local analog CATV service and add in some of their own channels on the same line feeding the rooms?
 
damn haven't seen one of those since there was one on my cable system back in the late 90s
The cable system at the time put two of them on your line if you had just "lifeline" cable. One "allowed 2-23 and 95-99" and the other one blocked 14-22.
 
damn haven't seen one of those since there was one on my cable system back in the late 90s
The cable system at the time put two of them on your line if you had just "lifeline" cable. One "allowed 2-23 and 95-99" and the other one blocked 14-22.
Oh I have one of those too.

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It blocks 2-72. Was used for internet only service before all the channels were encrypted. Can still be used to prevent receiver sharing to internet only addresses.

I'm not sure what the notch filter blocks because I've tested it on the line and can't find anything getting blocked.
 
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Usually the frequency is one of the numbers.

What would you do with the knowledge?

We have enough users trying to find some reason their birth year is significant. ;)

If I had to guess I would say it's supposed to block 14, 18, and 28 through 35 unless the + means it allows 28 though 35.

If memory serves me right back in the early 90's on many cable systems HBO was on channel 14 and Showtime on channel 18.

This may have been used on Paragon cable along with one of these converter boxes.

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If I had to guess I would say it's supposed to block 14, 18, and 28 through 35 unless the + means it allows 28 though 35.

If memory serves me right back in the early 90's on many cable systems HBO was on channel 14 and Showtime on channel 18.

This may have been used on Paragon cable along with one of these converter boxes.

View attachment 169329

I remember those. My friend had cable and used one of those to switch channels in the 80s. Even back then it always seemed antiquated to me. :rolleyes