Icom ic-m411 vhf - Tx fine, Rx doesn't properly detect incoming signal.

Mark-1

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I have a icom-m411 that doesn't receive transmissions unless you turn the squelch to the point where background noise kicks in.

Eg: Turn squelch to the point where the noise is suppressed, transmissions not heard and the 'busy' text never shows. Turn the squelch to the point where the noise is constant and 'busy' text permanently visible and transmissions are heard clearly over the noise.

I've swapped in different sources of transmitters (Marina + Handheld) + the boat Antenna and a 2 foot bit of wire I plugged in the back. Behaviour is identical regardless of transmitter or antenna.

It's long out of warranty, and possibly destined for the skip, so I won't be getting a pro involved but I'd like to fix it myself if possible.

What's wrong with it?

TIA.
 
I have a icom-m411 that doesn't receive transmissions unless you turn the squelch to the point where background noise kicks in.

Eg: Turn squelch to the point where the noise is suppressed, transmissions not heard and the 'busy' text never shows. Turn the squelch to the point where the noise is constant and 'busy' text permanently visible and transmissions are heard clearly over the noise.

I've swapped in different sources of transmitters (Marina + Handheld) + the boat Antenna and a 2 foot bit of wire I plugged in the back. Behaviour is identical regardless of transmitter or antenna.

It's long out of warranty, and possibly destined for the skip, so I won't be getting a pro involved but I'd like to fix it myself if possible.

What's wrong with it?

TIA.


Known problem with some Icom kit. Both PMR and Marine.
There is a ceramic filter in the Rx circuit that is known to fail.
Although the unit is quite ancient, you may well find that a polite telephone call to Icom,01227 741741 with the information that you think all ICOM kit is wonderful but that you have an ancient one that appears to be a bit deaf, may possibly result in them asking you to post it back for FOC repair.
They have done so in the past.
Try that with all the other marine radio purveyors and see what answer you get :)
 
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Many thanks all three of you, I took your advice and glad I did. It sat on my shelf for a few months but I posted it Monday morning, and got it back this morning fixed and returned free of charge. Zero hassle. Breathtakingly good service.

They spelt my name wrong on the "zero" invoice, should I write a strongly worded letter of complaint? :D

Don't push your luck......☺��☺
 
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