The ifhp filter supports the AppSocket protocol used by Tektronix. You will need a printcap similar to the following:
phaser:
:sd=/var/spool/lpd/%P
# need a dummy device for output
:lp=/dev/null
# You need to specify the IP address of the printer's network interface
# In this example it is 10.0.0.1 - replace with the correct value
# The filter will actually open the connection.
:filter=/usr/local/libexec/filters/ifhp
:ifhp=dev=10.0.0.1%9100,model=tek