thats just a female-female F coupler
are you using screw on males ? or compression ones?
screw on http://cpc.farnell.com/pro-signal/rw6-022-c-zinc/f-male-twist-on-rg6u-zinc/dp/CN16028
compression http://cpc.farnell.com/pro-signal/rw6-083c/f-compression-plug-rg6u/dp/CN16032
One end from the virgin cable is the screw on type connector. The other is the type you see in my picture. Above