[Repeater-Builder] Johnson vhf crystal repeater part number

[NORM KNAPP]

Hi,
I got a preselector from a vhf johnson repeater. It has 9 slugs in it and 4 RCA 
jacks on it. It appears to have a built in preamp also. Is that what it is? 
Does it have a built in preamp or is that a mixer? Part number is TLE8023APR.
Thanks!
73 de N5NPO 
Norm