IF you can view the back panel ports you can see if there's a 480i selector switch (with other resolutions) or composite video/audio out--which is analog so long as it's not labeled 'coaxial' if your TV (or VCR connected) supports S-Video input look for such an output from the tuner. that should work, too. (S-video ports usually look like keyboard/mouse ports used on computers but are audio/video instead)
Composite analog out is usally yellow (video) red (Audio right channel) white (Audio Left Channel) and coaxial is labeled like yb, py, etc. colors are different too. in the event your TV or VCR connected isn't stereo, use the white plug and leave the red one omitted.
If you can grab a free *.PDF manual from somewhere you can find out through that what inputs go to what, which resolution to select, etc.
I use a Samsung SIR-T451, and, while it's technically an HDTV Tuner, and not a 'converter box,' it does support DTV and analog outputs and modes are there. works fine, in fact--better than the cheap converters sold for the coupon program.
As long as you pick up a receiver without a Tivo or DVR (so the H20 or H21 won't work) and it has a functional access card in the receiver (but no subscription), you'll be able to view over-the-air channels with it.