Interesting alternate argument, Colin.
I appreciate your and everyone else's thoughts here.
At least if we don't ever totally figure out the answer, we all may learn
something in the process.
Tom Behler: KB8TYJ
----- Original Message -----
From: "Colin McDonald" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Thursday, December 13, 2012 4:00 PM
Subject: Re: Accuracy of TW1 Talking SWR/Watt Meter
> don't forget, the 590 takes power and swr readings pre-internal tuner, and
> the tw1 takes them post internal tuner...weather you have the internal
> tuner
> on or off, this probably accounts for some of the discrepancy.
> The tw1 is also a more sensative instrument than whatever the radio uses
> inside, so RF, capacitence and that kind of thing will effect it's power
> and
> swr readings much more so than the internal measurements.
>
> Like Butch, I would tend to believe the tw1 before any internal
> measurements
> for the reasons he mentioned.
>
> 73
> Colin, V A6BKX
> ----- Original Message -----
> From: "Tom Behler" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Thursday, December 13, 2012 4:57 AM
> Subject: Accuracy of TW1 Talking SWR/Watt Meter
>
>
>> 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
>
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