Batboard

Folks:

I am trying to do some coverage plots and I need to find out the gain of the antennas in VHF R2 band. Is it somewhat like < 2.1dBi ?

Akash

More like -4DBD or less than half of a reference dipole. DBi is the reference to a Isotropic radiator that is almost 1/2 as good as a reference dipole. Hence +2.5 DBi would be almost the same as a dipole, or 0 DBd.

Estimating the performance of a portable antenna is a very important part of coverage prediction.

Optimally, you would use the specific recommendations of the manufacturer of the radio and antenna.

If that data is not available, the values recommended in TSB-88 should be used.

Anyone who is attempting to predict radio system coverage professionally, whether for their own organization's use or as a service for a client, should be thoroughly familiar with the TSB-88 documents.

xmo wrote:Estimating the performance of a portable antenna is a very important part of coverage prediction.

Optimally, you would use the specific recommendations of the manufacturer of the radio and antenna.

If that data is not available, the values recommended in TSB-88 should be used.

Anyone who is attempting to predict radio system coverage professionally, whether for their own organization's use or as a service for a client, should be thoroughly familiar with the TSB-88 documents.

Agreed!

I generally use -10dB on plots for vhf hi-band portables after careful research and comparison considering the portables in use here and the way they are carried by the users. With uhf I use -3dB. YMMV