Alan, so what am I doing wrong? The following is all I see at the bottom of
the page. Clicking on ERP1.xls opens the March file. I can find no
reference to ERP2. When I find this will it give the correct answers for a
vertical?
Peter.
Click
here to download CVconv.zip (abt 85k)
6. Excel spreadsheet that calculates the radiation resistance of a
loop and a top-loaded vertical (Marconi) and calculated the aerial current
necesary to radiate -10dBw as allowed on the new 500kHz experimental allocation.
This spreadsheet uses the procedure that was in the old Loopcalac. However it
turns out that the radiation resistance i used for the inverted "L" was
incorrect by a factor of 2. The formula I used from the Admiralty handbook 1938
vol 2 turns out to be for a dipole. The radiated power quoted in this sheet is
the "total radiated power" which I think would be EIRP. I suggest that this is
more practically correct for amateur sized aerials than using the ERP figure
which is 2.8dB greater due to the directivity. The top-length figure may need
changing for very small aerials, and you will need to unprotect the sheet and
juct change to top row cell and the change should rattle through the sheet. I
suggest you protect it again to prevent accidental corruption.
Click here
to download ERP1.xls
