Hello all. We have a cross band repeater (Midland 100W VHF low w/ 1W VHF high band repeater built in).
What we noticed is that in the High Band --> Low Band direction, the high band side will receive the signal, then the low band Tx will key up to repeat the signal. Normally, all works just fine. But at extended distances, the low band TX keying up will deafen the high band side trying to copy the faint signal (from an HT), resulting in a choppy, unintelligible signal at the max distance. This is only with a faint/distant enough signal, like a HT at a distance. In the other direction (low band --> high band), there is a HUGE increase in maximum distance, even with just 1W from the high band Tx going out, since it seems to be not enough power to desense the low band Rx. Long story short, will adding a high pass filter to the high band side to shield the high band Rx from the powerful low band Tx do the trick? Where can one find such a thing? It just has to pass from say, 100-120 Mhz, and block everything below it, and tolerate 1W of Tx power is all. We'd like to avoid using a big, bulky cavity filter if possible, since we don't need monster isolation figures, or high power handling capabilities. Thanks in advance for any ideas!