Using Internet Coaxial Connection as Tuner Antenna

Way back when I was a sophmore at Heidelberg College in Tiffin Ohio (1984-1985), I plugged my radio antenna into the cable coaxial protruding from the wall and was instantly able to pick up Detroit Wheels and stations from Windsor Canada. Mind you, these stations were at least 100 miles or so away and I did this with a radio and not a receiver or a tuner. I now have a Magnum Dynalab tuner and a PS Audio Power Station and have been cogitating over whether or not I should place a splitter on the power station and then run 1 coaxial to my internet modem and 1 coaxial to my antenna input on the tuner? Right now I'm using the Magnum Dynalab ST-2 antenna inside the 2nd floor apartment window. Come on, there have to be others who have done this.
Well you don't have to buy a splitter to try it. If it works great if not you saved yourself from wasting money on a splitter. That said most likely the jack you used in the 80's was hooked up to an antenna not cable. The cable tv jack should not be acting as an antenna. Since you are using that jack for your cable internet we know it is not hooked up to an antenna. I have seen some older apts that have both cable and antenna jacks in the same room.

If somehow you can pickup fm on the cable jack be aware that installing a 2-way splitter will lower the signal to your modem by 3 db's. This may or may not be a good thing depending on how strong the signal is.

Thanks Sean,
Much appreciated advice as your comments add a perspective that's obviously founded upon practical sense. I'll seek out other antenna options.
Might I suggest that you don't put a fork in the toaster.:-)
Sure enough, cheap thrills no longer interest me.
The main reason you heard stations at such distance. is because of where you were. Tiffin isnt very far south and Canada broadcasts stations at double the power of USA radio stations. In western Cleveland you can easily pick up 89x out of Windsor only failing to pick it up when John Carrol University radio station simply over powers it.
Yes, this is a valid point. I'm in Cincinnati now and wanted to pick up a station in Dayton and in Yellow Springs but cannot with a dipole antenna. Tiffin to Detroit would be more than the distance between Cincinnati to Dayton. As stated initially, I did this as a sophomore in college which was 1984 and so my assumption is that various factors back then could have been different from today, i.e radio signal compression
Quality is an issue but most stations stream over net these days, better than nothing.
Its funny that you should mention audio streaming as I recently bought a higher end DAC for this very reason. The BBC Radio 3 at 320 kbps is about the only station that I'm able to withstand. I even wrote the BBC asking them to offer full resolution streaming audio via paid online membership; yes, I can only hope.
If you want a splitter, Goodwill will have them for $1 or thereabouts. If it doesn't work, donate it back for good karma. Good luck!
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Hifigeezer, thanks but I tried it and there is no advantage over using my Magnum Dynalab antenna. Prior to the digital box, I used to use the cable outlet as a TV antenna and it worked wonderfully but that was at another location. I'm not sure why there are inconsistencies.