the filter will be only in the TX path, the roofing filter should also be in RX path.
why amplify all the mixes from the first mixer. A good change in the architecture of
IF the filter replaces R27 that may be true save for it can also behave as a suckout
(un intended RF short) as its along the path. Please test, as I hope for good result
but not testing it bugs me nuts. Testing says RX is good then you have done a