Harry; I switched out my Ray Jeff 513 and used the existing transducer. Replaced it with a Standard DS 30. The plug used by the Ray Jeff IS NOT an RCA plug. It only looks like one. The center contact is smaller. A good quality RCA plug, soldering iron, and lots of patience and all will work out fine. powell... M/S Fletcher James NAS Pensacola FL -----Original Message----- From: Harry Sodeman <nwfruit@televar.com> To: trawler-world list <trawler-world-list@samurai.com> Date: Thursday, 16 July, 1998 17:38 Subject: old style flasher/sounder >Hi listers.....How is the best way to upgrade from the old style >flasher/sounder to a modern fishfinder/sounder? Here are some of the >physical conditions that effect how to best proceed..... > > 1. the current non working unit is a Ray Jefferson 513 > 2. this unit has a 200khz thru hull transducer with a RCA type jack > 3. the boat has a ballasted hull...this is important because i'm not >sure you > can use a glue on inside hull transducer with a ballasted hull? > 4. the boat has a full displacement hull, single screw, horseshoe >shaped > stern with no flat surface or right angles... > > Has anyone tryed to use the existing transducer and just mount a >new unit that will accept the RCA jack? or who has any other >suggestions....thanks very much in advance..... > > Harry "Kalena" > > > p.s. The new fishfinders have a different connection from the >transducer...I guess to show the graphics or ??????? >