ICOM AT140 Problem?

[sailorphil9]

Hi

I'm considering buying a used ICOM M802 c/w AT140 tuner. It's off a GRP vessel whose sintered plate fell off at sea. The ground cable from the ATU has cooked - the entry to the ATU casing is blackened and the cable cover has melted over a short length (not all the way to the PCB).

I'm not in a postion to test the unit although I've been told that the 802 switches on with no error messages (not connected to the ATU) - the owner is unable to test the unit beyond switch-on as it's been removed from the boat.

I'd appreciate opinions on whether the overheating could have damaged the ATU circuitry at all.

Although in my ignorance I doubt that the main transmitter unit would also have been damaged, I'd also appreciate views on whether that is likely.

FWIW the owner was of the opinion that the ATU 'is not really necessary'. I have my doubts about that!


Thanks in advance for all input.

[Brian.D]

The ATU is not necessary only because there are many ATUs on the market to replace it. The ATU and the M802 are not a matched pair. You can replace the ATU with a SG230 and the radio will be happy.

The radio should have a high SWR protection circuit so if the ATU malfunctions the radio will either reduce power or stop transmitting. Should being the operative word.

I would think if the price is a great bargain then go for it. Like I said, you can use just about any of the major manufactures ATU: MFJ, LG, LDZ, Icom.

[Frankly]

Have you considered that you might be looking at a lightning damage unit (s).

In the end you will need an antenna tuner with typicall long wire antenna set up.


Frankly
KI4STS

[AA3JY]

I also highly suspect lightening strike/damage equipment..I’d get all associated verified as working before purchase...

Also I do have a SGC 230 that maybe willing to part with...

[sailorphil9]

Originally Posted by Frankly

Have you considered that you might be looking at a lightning damage unit (s).

In the end you will need an antenna tuner with typicall long wire antenna set up.


Frankly
KI4STS

Thanks. The boat is alongside me on the hard. I can see where the missing groundplate was. Mast and rigging laid up. All ok. New owner (refitting the boat after purchasee) thinks electrolysis. Boat is over 40 yrs old.



Also, the signal cable insulation terminal at the antenna side looks good. On balance probably not lightning IMHO.

[sailorphil9]

Originally Posted by AA3JY

I also highly suspect lightening strike/damage equipment..I’d get all associated verified as working before purchase...

Also I do have a SGC 230 that maybe willing to part with...

Thanks, I already have an ICOM M600 with AT130 which I picked up really cheap as a project - the TX side is non-operational and I suspect the ATU.

I just thought that I might get a good deal with the M802, but I don't want to find that the AT140 is useless and end up having to buy another ATU when I can just stick with the M600 and get a new tuner for that. Tight budget ;-)

I like the ICOM ATUs because they are well weather-proofed (as is the SGC230). I looked at the LDG (good price) but they don't appear to be very suitable for installation my lazarette...