RF mod doesn't work on all TVs?

[S1500]

Okay, here's a weird one. I got this TV from my former employer, but with one quirk to it. It has BNC inputs instead of coaxial. Oddly enough, it has an IN & OUT port(what's the OUT port for?). Anyways, I go get an adaptor at Radio Shack, and I think I'm good to go. Try hooking up a TI RF modulator to it, and I get nothing for a signal. I try it on a newer TV, same coaxial hookup & it works fine.

 

Am I SOL for the older TV? Guess I'll have to find that composite cable around the house that has non-working audio(it's slightly damaged). In fact, I don't think I've ever hooked up anything via the BNC connector on the TV. The only thing I haven't tried is putting a digital tv converter between it, and just hooking it up via s-video to the TV.

[+5-11under]

Does it look like a studio monitor? What's the model number?

5-11under

[S1500]

I'll have to take a look when I get home. It's I think a Toshiba. there's only 5 buttons on the front panel(power, volume up, dn, reset & something else). I have no remote for it. Strange TV. It used to be in the lobby of our former work place, hooked up to a cable TV running all day. No tuner I can find, yet I think in back there's a channel 3/4 switch. I tried both channels with the TI modulator to no avail.

 

I still have yet to try hooking up the smaller Comcast cable box(digital, but without the frills) via coaxial. Other than that, I know the S-video input works.

 

Hmmm, I wonder if the Colecovision would work.