Tom,

I always find the TW-1 to read low on power and sometimes (not always) a 
few ticks higher on SWR.  I am comparing this to readings I get from a 
Wave-Node unit, which has some audio feedback, and the meters on my amps 
and external tuners.   The meters in the amps and tuners need  sighted 
help, which I usually don't have here.   When I did have sighted help, I 
found that no matter what combo of radio, amp, and tuner, these  meters 
always matched or were very close to what I was seeing from the 
Wave-Node.  The TW-1 is always the odd man out.

This discrepancy  increases with power and frequency.  Less of a 
difference on 160, more on 10 meters.

The tones seem to work well in the TW-1.   If I tune for flat SWR with 
the tone, All meters will show 1.0:1 with the possible exception of the 
TW-1 which may show as much as 1.5:1 depending on band or antenna. 
Same with power tone.  If I tune for highest pitch, all meters will show 
max power, but the voice of the TW-1 will always read lower than the 
others.  Sometimes more than 100 watts difference, while the others are 
all pretty close to each other.

My TW-1 may be out of specs compared to what others have, or maybe it is 
correct and everything else here is wrong.  As someone said, it's just a 
hobby.

73, Steve KW3A


On 12/13/2012 6:57 AM, 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
>
>
>