[Elecraft] OT: Bird Wattmeter "meter failures"

[Robert Harmon]

Thanks for all the info on diagnosing the intermittent problem with my 
Bird 43 guys !
I discovered their was a poor connection where the RG58 from the meter 
movement
connects to the element.  As mentioned there is a tiny spring in the 
connector on the end of the
cable.  It didnt look dirty visually but I cleaned it with some contact 
cleaner and now is fine.
It was mentioned to change over to a BNC connector to eliminate 
problems.  I assume we mean an
adapter from the bird element connection point to a BNC.  Then add a BNC 
on the end of the short
RG58 from the meter movement.   Anyway it is working now, thanks guys !

73,
Bob
K6UJ



On 11/22/15 2:13 PM, Bob McGraw - K4TAX wrote:
> Ron mentions various well taken points regarding the Bird 43 meter 
> series.  This also applies to almost all watt meters as well, and that 
> is the power calibration is relative to a 50 ohm load only. Any other 
> load Z will introduce errors in the meter accuracy and indication.
>
> At the same time, the ratio measurement for forward power and 
> reflected power will always be correct in that each value will be 
> measured with the same degree of error.  Thus using this information,  
> one can accurately calculate the SWR using the forward power indicated 
> and the reflected power indicated.   Where as, absolute values will 
> not necessarily be accurate under these conditions.
>
> 73
> Bob, K4TAX
>
> On 11/22/2015 11:38 AM, Ron D'Eau Claire wrote:
>> Bird instruments specs a Bird 43 at plus or minus 5% of full scale. 
>> If you have a calibrated 1000 watt slug and meter it will read within 
>> 100 watts of the real power. What many people miss is that the 
>> possible 100 watt error is constant over the range of the meter, so 
>> measuring 500 watts the meter will indicate something between 400 and 
>> 600 watts and at 100 watts the reading can be off by a full 100%!
>
>
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