Is it possible for a 20" antenna to have gain on VHF?

[JoshuaHufford]

Was just looking around on the antenna farm website the other day at different antennas, and looked at these two.

This one is 20" tall and specifically claims 3dBi of gain on VHF,

https://www.theantennafarm.com/catalog/laird-technologies-wpd136m6c-001-4286

This one is 22" tall and claims 2.14 dBi, not being specific as to what band.

https://www.theantennafarm.com/catalog/pctel-pctwslmr-8504

All of the other multi-band antennas in this height range are usually unity gain on VHF and then have some gain on UHF which makes sense. Just wondering if this is a typo, marketing hype or if somehow they are really getting some gain out of a short antenna?

 

[KevinC]

2.14 dBi is the same as 0 dBd, so no gain.

dBi uses a "theoretical" antenna as the reference.

Antenna Gain dBi vs. dBd - Ham Radio Academy

How does antenna gain stated in dBi compare to gain stated in dBd for the same antenna?

hamradioacademy.com

 

[JoshuaHufford]

Ah ok, thanks for the link. I need to do more reading on this to get my head wrapped around the difference between dBi and dBd.

 

[KevinC]

Ah ok, thanks for the link. I need to do more reading on this to get my head wrapped around the difference between dBi and dBd.

dBi is referenced to a non-existent theoretical antenna, dBd is referenced to to real dipole antenna. Companies usually use dBi as a marketing gimmick.

 

[iMONITOR]

Is this a base or mobile application?

 

[JoshuaHufford]

So it is just marketing, thanks.

Is this a base or mobile application?

The two antennas I linked were mobile antennas, although I wasn't really looking for anything for a specific application, I was just looking around, window shopping.