interlacing artifacts on copy but not on source

The subject might be a bit misleading but one can put only so much in a
subject line.

I have a DVD which I am trying to rip to my PVR.  The source material is
720x480x29.970 and is definitely interlaced, which is not surprising
given the framerate indicates that it was likely videotaped at source,
not filmed.  This is what mplayer -v has to say about it:

MPEG-PS file format detected.
Searching for sequence header... OK!
VIDEO:  MPEG2  720x480  (aspect 3)  29.970 fps  9800.0 kbps (1225.0 kbyte/s)
[V] filefmt:2  fourcc:0x10000002  size:720x480  fps:29.97  ftime:=0.0334

When I play this on an interlaced television it looks great.  No
interlacing artifacts can be seen.

I tried to make an "exact copy" of this DVD by setting my final rip size
to 720x480 as well, without any zoom, crop, de-interlacing or filters,
etc.  This is what mplayer -v has to say about my ripped copy:

AVI video size=1294701368 (149993) audio size=280336896 (280336896)
VIDEO:  [DIVX]  720x480  24bpp  29.970 fps  2069.5 kbps (252.6 kbyte/s)
[V] filefmt:3  fourcc:0x58564944  size:720x480  fps:29.97  ftime:=0.0334

The above rip is also interlaced, but when I play it on the exact same
television using the exact same video playing software, it is displaying
interlacing artifacts like crazy.  I can only guess that the interlaced
frames in the copy are not being displayed in the correct phase with the
interlacing of television (if that phrasing is at all meaningful).  What
I mean is that perhaps the odd/even frames in the rip are being shown on
the even/odd frames of the television -- opposite of what they should be
showing.

Any ideas?

b.

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