I've added some info to my Navy receiver page - http://www.virhistory.com/navy/navy-rcvrs.htm Contract NObsr-71289, 27 April 1956 for 75A-4 and 75A-4 (Mod) Manual is NAVSHIPS 92788 75A-4 (Mod) has the following bands: 1.5 to 2.5 mc 3.2 to 4.2 mc 4.2 to 5.2 mc 6.8 to 7.8 mc 13 to 14 mc 14 to 15 mc 29 to 30 mc cheers, Nick K4NYW