Conquest systems both four and six channels were sold in vast quantities before and after the 1991 narrowbanding In AM, FM as well as 512 PCM. As noted above all the FM Versions and the PCM units are considered narrow band however most of the pre 1991 AM units are not narrow band and illegal to use unless they have the gold RCMI sticker to show it has been narrowbanded and none of the original Rx could be narrowbanded and had to be replaced.

If the radio system is AM and without the sticker for purposes of the buy I would consider it worthless.

John