A good quality diplexor works. Go to loews or home depo or electronics plus. The package will say it passes the low band, below 52 meg. Ive done it a doz or so times myself. The higher quality diplexers are about 12 - 15 bucks. There is a multi switch that is by blonder tounge i think that works to.
This is CABL.com posting #136009. Tiny Link: cabl.co/mJxR