Gary,
Aah! That's where the 'rough science' part comes in. I used my Jap. Daiwa
(that is at least spec'd down to 1.8 MHz) as reference! Actually the Daiwa
correlates quite well against the Bird on HF. Perhaps Bird use these to do
their production cal. against ;-)
I was expecting the 250H to exhibit a bit more (some) droop than the 2500H,
but couldn't really discern any. Perhaps a 50H would show some?
Regards.
Mark.
-------------------------------------------
At 17:38 29/03/2005, you wrote:
>Mark Hill wrote:
>>Anyway, to get back to somewhere near where this thread started. I did
>>some rough science checks on a 250H Bird 43 insert. I did not find that
>>using it resulted in readings that were dramatically low just below 2
>>MHz. I checked down as far as 1.6 MHz and would say that any additional
>>error from using it at frequencies down to this far below its lower limit
>>was negligible.
>>My personal conclusion therefore is that both 250 Watt and 2500 Watt 'H'
>>series elements are good to go on topband. If anyone has other 'H'
>>series ones, I would be interested in any results they collect.
>
>What method did you use to measure power to compare the bird to?
>
>Note that the higher power the element the broader band it is. Don't
>expect the 250H to be the same as the 2500H.
>
>73
>Gary K4FMX
>
>
*******************************************
Mark Hill - G4FPH
E-mail: g4fph@mjha.co.uk
Current web pages at: www.qsl.net/g4fph
Old web pages at: www.g4fph.freeserve.co.uk
-------------------------------------------
Dipoles resonant on 1942/3695/7065 kHz
2 ele delta loop beam resonant on 14180 kHz
-------------------------------------------
Remember - SIDE for HV safety:
S witch off
I solate
D ump
E arth
*******************************************
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