[ICOM] Icom Tuning?...Help Please

[Larry Winslow]

I'm not familiar with the 290A but all of the 
Icom rigs I've had use an encoder - except for 
the early ones which were crystal controlled.

If it is an encoder, a scope put on the 
"wiper(?)" should show blips when the knob is turned.

73 - Larry WØNFU
larry_w at comcast.net

At 10:44 PM 9/12/2006, you wrote:

>
>Hi,
>I have an Icom IC-290A that I am working on...The problem being that when I
>turn the tuning knob it doesn't change frequencies,it acts as if the knob is
>slipping.
>After determining that it wasn't the knob slipping I proceeded to
>disassemble the front to get at the tuning potentiometer.
>If your familiar with this unit you know that the potentiometer is
>continuous and has teeth that catch when you 
>turn the knob to make tuning  easier.
>Now when I hook up my ohm meter to the wiper and to either end of the
>potentiometer all I get is an OL reading and 
>when I turn the shaft the reading
>jumps around wildly. If I connect the meter to 
>the wiper and to the case of  the(I
>am assuming this is correct?) potentiometer I should get a reading of  Zero
>ohms but again the only reading I get is OL.
>
>Am I safe in saying that the potentiometer is bad?
>
>If so how do I go about figuring out what type of potentiometer I need to
>replace the bad one?
>The schematic doesn't tell me what value it is and there isn't a parts list
>or part number either.
>
>
>I hope I have made myself clear enough to be understood,if not please let  me
>know so I can try and make things clearer.
>
>
>Any help on this would be greatly appreciated.
>Thank you
>
>----
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