Re: EMF Calculation - No Inverted V #EMF


Den (M0ACM)
 

Dom,

A final final on this thread (!) I have just delved into the data tables using a recent version (but not 11a) of  the RSGB calc and confirm that "generic" (but not manufacturer/model specific) data is used by the table. 

The gain figures used for 2m and 70cm for the "collinear" option are 6.5dBi and 8dBi respectively and the data for 2m, 70cms and 23cms (!)  for the "big collinear" are 8.3dBi, 11dBi and 14.8dBi.

To clarify re the "use different ant" message, the calculator looks at the gain returned from the tables after you choose the antenna. 
If the gain comes back as "1", it sees that as not having found a "real" gain figure in the lookup table and pops up the "use different ant" message to advise that any results figures will not be reliable. 

Ok, coffee time !

73

Den


On Fri, 22 Oct 2021 at 10:23, Den (M0ACM) via groups.io <denf.acm=gmail.com@groups.io> wrote:
Dom,
I have just done a run on the IcnirpCalc and attach results page for 6M for the V2000.
I have assumed some pretty 'standard' condx with 15m of RG213 and an ant height of 5m
Mode FM and 50% TX:RX with 100W from TX
You will see it suggests a "Safety Distance" (EZ) of 1.68m.
144MHz with the same setup advises an EZ of 2.52m
Hope that helps
Den

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On Fri, 22 Oct 2021 at 01:50, Dom (2E0WHQ) <domwilko@...> wrote:
Thanks Den,

I was just trying to get ahead of the game by checking my HF antennas. I'm fine with my current 2m/70cm Colinear setup, mainly due to my Diamond V2000 antenna being 5.5m up on a scaffold pole half way down the garden. Curiously though, the calculator won't allow me to use the same Colinear antenna for 6m. It asks me to 'use different antenna'. The V2000 is a tri-band Colinear covering 70cm, 2m and 6m, but the calculator won't allow you to use a Colinear for 6m.



If I continue with the Colinear, it says I'm compliant based on height, as does the calculation if I use a Vertical Dipole as the 6m antenna.

Whilst the calculator is good, it's clear that there are still quite a few issues with it. I'm sure they'll get ironed out over time.

73

Dom.

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