With lots of Icom IC-705 rigs now owned my Famparc members, I stumbled across this great feature which I have not used before.
Most radios have these feature, so it's not unique, but this helped me lots in receiving a low signal.
Running on FM to a local Repeater that I have problems in receiving, I played around with Filter, Noise Reduction etc.. but, using the Receive Pre-Amp, WOW.. the change in receive signal and noise floor was amazing. SN Ratio
The quick video demonstrates having the Pre-Amp on and off when receiving this low signal from VK3RSU Repeater.
Try it for yourself on a low signal on say FM..
You will hear the difference between the SN ration on receive between the Pre-Amp on then off.
Have fun with your IC-705. I am !