Modifing uhf frontend for more gain

[iw2evk]

Hi,
i've a Commercial UHF transceiver ascom se 540 turned in ham radio band.
The radio work fine , but checked with a ham radio have less sensitivity ( i suppose 0,3 microvolt or more for 12 sinad)
It's possible modify the frontend circuit for get more gain like a ham radio uhf transceiver?
I've notice of this modification in frontend stage of kenwood ts 2000 and others radio.
Whath are the componet to change and whath are the right value?

Thanks

Roberto iw2evk

Milan

[kb2vxa]

Standard is .25uV so what's wrong with .3uV?

[iw2evk]

Hi,

in this kind of radio the squelch it's setting by a trimmer and ca't be modified during use.
The low signal station don't open the squelch.if i connect a ham radio transceiver the squelch open ad i listen the qso.
Note : it's not a squelch problem, because if i run se 540 with full opening squelch i can't heard the qso because the signal it's very low (poor sensitivity).

[jhooten]

If it was my radio the first thing I would do would be to take it to a technician familiar with the brand and having the proper equipment to do a full alignment on the receiver before I started to to modifications that may prove to not be needed. IF it is properly aligned and the desired signal still cannot be heard the next step would be to borrow an external preamp to make sure the extra sensitivity will allow you to hear what you want to hear without being overloaded by strong signals close to the chosen frequency.

Just a suggestion.