navico axis rt1400

Could it be a mini-DIN, like a PS/2 mouse or keyboard? The outer shell on these is about 9.5 mm diameter.

US Citizens Band radios and some other mobile radios used a series of round connectors like this

starting in probably the 1970s. The 4-pin type was most common on a CB but they exist all the way up to 8 pin. The female connector has a threaded ring that "floats" on the body of the connector and is used to secure the two halves together. The individual pins are much larger diameter than the ones on a DIN connector.

The bare minimum is probably three wires: earth/ground/shield, mic audio, push-to-talk. If the original microphone had other features like channel up/down buttons or a channel display, that's what some of the other wires are for.

Simrad seems to have gone to some lengths to make the manual for this radio unavailable online.

suggests that it used to be available, but Simrad's site from that era has too much Javashit for archive.org to deal with. I found a slightly later version of their site but archive.org didn't catch the zip file with the manual. Their current site doesn't list it at all.

There is a manual for the Simrad RD68 VHF radio on a third-party site

or and on PDF page 64 it mentions that the "fist mic" for the RD68 is the same as the one for the RT1200 and RT1400. Several of the schematic pages are also labeled RT1200/RT1400. PDF page 37 has the schematic for the "fist mic", and it is as simple as audio, PTT, and ground - no pin numbers though. PDF page 38 has a schematic for a slightly more complicated handset? which uses more wires - still no pin numbers.

Matt Roberds

Unless you have to keep as original, remove the socket and replace with something easier.

Thanks for the service manual . I think i have found the mic gnd and ptt pins from the circuit in the manual a great help thanks.

Will try and find a socket that will fit from the spares box . Space is lim ited as original is pcb mounted. Otherwise its a gromet and wire it in. The chandlers were very scathing about the navico seemed to think it was prehi storic or something they should have seen the seavoice its replacing !

Will try and find a socket that will fit from the spares box . Space is lim ited as original is pcb mounted. Otherwise its a gromet and wire it in. The chandlers were very scathing about the navico seemed to think it was prehi storic or something they should have seen the seavoice its replacing !