Hello Josh, Years ago I had copper pipe duplexers for 220MHz and they worked OK, but were not temperature stable. I had to tune them at least twice a year, summer and winter. I would be afraid that this may be a problem for you, especially on 6 meters. Purchasing large diameter copper pipe can also be quite expensive. Short pieces of 1 5/8 hardline are not difficult to find if you have a contact in the cellular business. See if you can find a tower company in your area and ask them for scrap pieces.
73, Joe, K1ike pet_the_dogg wrote: > I am getting all the materials for a 6 meter repeater, but am hung up on a > solution for a duplexer. I have seen several paces showing how to make a > notch duplexer with heliax made into 1/4 wave stubs. Since I am unable to > locate any large heliax,I was wondering if copper tubing could be used as a > similar replacement. It would seem to work since the heliax just forms a > folded dipole. Any experience would be greatly appreciated. > > Josh > KC9LGV >