Looking at the possibilities

[JamesBrox]

Laird YS1503 Yagi Base Antenna | Scanner Master

Laird YS1503 Yagi Base Antenna

www.scannermaster.com

I want to fine tune (trim) this yagi for 160-162 MHz RX only. How would I go about it?

 

[mmckenna]

Would depend on what the antenna is actually tuned for now. It claims 150-174, so it's probably tuned in the center there, which would likely put it right around 162MHz. Only way to know for sure is to contact the manufacturer and ask them, or hook one up to an analyzer.

Also, that antenna in the photo is -not- a VHF yagi… Looks more like an 800MHz antenna.

Trimming the element length would adjust tuning, but wether or not it needed to be shortened or lengthened would depend on where it is now. Also, consider that these may be broadbanded enough that tuning would make little difference in performance.

There are companies that make tunable Yagi antennas. If you have not purchased this one already, you may want to look at other optoins.
This one is tuneable:

PCTEL MYA1503KN - 88-260 MHz VHF Yagi Antennas

150-174 MHz 7.1dB VHF Yagi Antenna. Connector N Female, Overall Length 3.5'

theantennafarm.com

 

[buddrousa]

The more important question is why do you have to tune this antenna is the SWR high?
Not knowing what you are doing and not having the tools to work with could cause you more problems than it could fix.

 

[scanmanmi]

Ya that does look short. Maybe something like this. It has UHF connector.

PCTEL MYA1506K - 88-260 MHz VHF Yagi Antennas

150-174 MHz 6 element VHF yagi antenna. 10.2dB gain, 300 watt. Direct UHF female term. Includes mounting hardware

theantennafarm.com