SWR meters often become inaccurate when the SWR is high.  An infinite SWR
would mean that the forward and reflected power are equal, at least on an
ideal meter.  It would be good if you could tell whether your internal or
external tuners were adequately compensating for the high SWR at the band
edges.  Remember, your resonant frequency is 1.830 MHz, not 18.300.  It
sounds like things should be reasonably safe from 1.8 to 1.9 MHz, at least.
73,
Lloyd Rasmussen, W3IUU, Wheaton, Maryland
Home:  http://lras.home.sprynet.com
Work:  http://www.loc.gov/nls
 
> -----Original Message-----
> From: For blind ham radio operators [mailto:[log in to unmask]]
> On Behalf Of Tom Behler
> Sent: Tuesday, November 15, 2011 6:32 PM
> To: [log in to unmask]
> Subject: TS590 internal watt and SWR meter VS LDG TW1
> 
> Hi, all.
> 
> As I have been working on tuning my newly-installed 160 meter half sloper
> antenna, I have noticed something interesting, when comparing the SWR's on
> 160 meters that are given to me by the TS590 internal meter, and the LDG
> TW1
> talking watt meter.
> 
> What I have noticed is that the TS590's meter gives me a 5 to 1 SWR at the
> top and bottom of the band, with the lowest SWR at about 2.0 to 1 around
> 18.300 or 18.400 MHZ.  Also, the TS590's internal auto-tuner seems to tune
> the antenna from the top to the bottom of the band with no problem.
> 
> Interestingly, though, my TW1 starts out ok with farily similar readings
> to
> those given by the TS590's internal meter, but as I get to the top of the
> band, its SWR readings shoot up to about 12 or 13 to 1, in comparison to
> the
> 5 to 1 given by the TS590's internal meter.  All readings are taken with
> the
> TS590 auto-tuner in the off position, and with an output power of
> approximately 30 watts.
> 
> Would anyone have an explanation for these variations I am seeing?
> 
> I do not seem to notice this much of a variation on other bands.
> 
> As a side note, due to the fact that the MFJ 259B analyzer I am borrowing
> gets confused because of the A M broadcast station in my area, I honestly
> don't know what the resonant frequency of the antenna is, but I think I am
> reasonable in saying that it's probably not too far from 18.300 or 18.400
> MHZ.
> 
> 73 from Tom Behler:  KB8TYJ