You could very well be hitting that one dirty spot on the roller inductor.
----- Original Message ----- 
From: "Michael Ryan" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Sunday, November 10, 2013 8:54 PM
Subject: Re_ATU Issues


> Hi Steve:=20
>
> Well 1ST up, my tuner is very old. I bought it last winter from a Guy =
> who was the 3RD owner of it. So, its probably in access of 15 to 20 =
> years old.=20
> It probably needs a good cleaning no doubt. There was no fluctuations in =
> the SWR or full power out when the antenna was directly connected to the =
> 570. I got my XYL to look at the display for that one.=20
> The flux only occured around 3.79MHZ with the MFJ-989  and I had to =
> rotate the roller inductor knob about 10DG clock or counter clock wise =
> to keep the SWR flat.=20
> So, this is how it goes. I tune for the low SWR, unkey, key up to check =
> and the SWR would be up to about 10/1. I'd key again and rotate the =
> roller inductor again to lower the pitch and SWR, take a reading and it =
> would be flat. I would receive for about a couple of 2nds and want to =
> take a reading so would key up and boom, the SWR would pop back up =
> again.=20
> All other bands perfect. Almost something might be arcing in there but =
> don't see any sparks or hear any crackling or smell any smoke. LOL=20
> The thing is, if it was the roller inductor, wouldn't that occur on all =
> bands or it depends on if you happen to hit that spot that might be very =
> dirty? The tuner is rated at 2KW SSB/1500W CW, my rig is rated at 175W =
> CW, so don't think 75/80W is too bad.=20
>
> 73:=20
> Michael DE VO1AX=20