You said it identified both cable and OTA.. it should not. It should identify one or the other, if it identifies both you have a problem.
Likely you set the antenna switch to ANTENNA.
The Antenna switch: Some folks have a matrix switch (Box of many buttons) like I do.. Many have a wall plate. it has a 12 volt outlet, an antenna connection (often to the main TV) a light and a switch,, LIGHT OFF for cable,, Light on for OTA but sometimes cable will sneak through the switch.. poorly.
Finally: Most cable systems now days broadcst QAM Digital, some still do analog (AND QAM) but some are getting greedy,, They broadcase ENCRYPTED QAM. What does this mean:
Some televisions, including the only US made 19" TV, do not accept QAM so you need a box from the cable company.
And if the cable company is encrypting.. You need a box no matter.
I am most familure with two cable systems. One is Darien Telephone, Darien GA, (Analog and QAM)
The other is the service in Richfield, TWP Mi.. Not sure which one it is.. But they are the same, Analog and QAM.
At least two other ssytems are going encrypted as I type.
Home was where I park it. but alas the.
2005 Damon Intruder 377 Alas declared a total loss
after a semi "nicked" it. Still have the radios
Kenwood TS-2000, ICOM ID-5100, ID-51A+2, ID-880 REF030C most times