how to print with troff on a UNIX pc?

[Steven R. Houser]

I'm trying to print files with troff on a UNIX pc with v. 3.51 UNIX.  I
have a Hewlett-Packard DeskJet connected to the machine.  When I used
nroff, I just piped the output to lp.  But when I print troff files from ua
or pipe them to lp, the DeskJet just prints raw troff output like this:

x T post
x res 720 1 1
x init
V0
p1
x font 1 R
x font 2 I
x font 3 B
x font 4 BI
x font 5 CO
x font 6 H
x font 7 HI
x font 8 HB
x font 9 S1
x font 10 S
s10
f1
H720
V480
h4270c1

Why does my printer just print this instead of interpreting it?  Do I
need to pipe it to another device?  Or doesn't the DeskJet understand
trofftroff?  The DeskJet is supposed to be LaserJet compatible.  I have my
ua printer setup configured for the LaserJet, and never had any problem
printing nroff on it.

Steve 
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