standard horizon remote access microphone

[geoff]

I have an older standard horizon dsc radio with a remote access mike[in the cockpit] it has worked very well for 15years !! now however it will only receive on the remote ,not transmit. All other functions work fine including the mike on the set . No discontinuity is apparent between outside mike and set . Spares for this model of handset are no longer available CMP23b. Any ideas ? Geoff

[tckearney]

The microphone failed on mine, sound the same on yours

[Lyra]

don't know this set but:
1. Is it only a mike or also display - for the former it might be possible to improvise a replacement with any mike
2. Is it serviceable (can you open it)?
2.1 Could be the mike element as already suggested - maybe can be disassembled and a suitable replacement put instead
2.2 Could be the PTT button contacts - I guess this would also be easy to replace

[geoff]

I have indeed taken it to bits. It is not only a mike but also loudspeaker and controls all vhf functions .The press to transmit clicks and a carrier wave can be heard by another receiver but no voice is heard . .....the mike and loudspeaker are one unit so I assume that if it works as a loudspeaker it should work as a mike.Geoff

[tckearney]

I'm surprised it is one piece IE Mic and speaker, but this si not unkown, mine must have been a different version.  I measured the mic in ohms against a known good mic from a friend’s boat.  Mine was a much higher reading.  I found one a similar shape in an old mobile phone  (about the same vintage as the VHF ) and fitted that, worked a treat.