Tom,

Regarding accuracy, I'd go with the 590's meter.  The 5% accuracy spec 
is probably best case, and not typical.

Steve


On 12/13/2012 06:57, Tom Behler wrote:
> Hey, all.
>
> As I have addressed my most recent issue with the TS590 DC power cable, I
> have noticed something interesting with my TW1 swr/watt meter.
>
> Actually, I thought I already knew this, but my most recent readings have
> reminded me of the issue.
>
> Now, with both of my TS590 power cables, when the rig is set to 100 watts
> output, I consistently get 100 watts as a power reading on the TS590's
> internal meter.
>
> However, when using the LDG TW1 talking watt meter, my readings can vary
> anywhere from 85 to 91 watts, with occasional dips as low as 81 watts.
>
> Keep in mind that all of these readings are taken on a resonant frequency
> with my Alpha Delta DXCC antenna and an SWR of 1.0 to 1.  Also, I get the
> same reading variations with the TW1 when using a dummy load.
>
> I checked the TW1 manual, and they clame an accuracy of plus or minus 5
> percent on 14 mhz, but I think that is debatable.
>
> On the other hand, do we know how accurate the TS590's power meter is as
> well?
>
> I'm not one to quibble over 10 or 15 watts, but I find the inconsistent
> readings with the TW1 to be at least interesting.
>
> 73 from Tom Behler: KB8TYJ
>
>
>