Question about RCA VKT-650 VCR

[8traxrule]

I just scored one of these from Ebay, been looking for this since it's one of the few models that plays both Hi-Fi and linear stereo- 99% of hi-fi models will only play the linear track in mono, which has driven me nuts for more than 30 years.

I played with one that a friend's mom had a long time ago (unfortunately I couldn't track it down later offering to buy it), and know that instead of Dolby noise reduction for the linear tracks, it has what is called a "Hi Filter". I'm guessing that this works the same as Dolby NR but they didn't want to pay Dolby licensing fees for it. I can't find a manual that explains this, but wondering if anyone else knows this machine well and whether it really is a carbon copy of Dolby NR. Right now I have an industrial model Panasonic VCR with both Hi-Fi and linear stereo, but it can't play tapes at LP or EP speed (seems none of the pro models can.) So for those tapes, I also have one Hi-Fi VCR hooked up that doesn't have linear stereo, plus another VCR with linear stereo and no Hi-Fi. Having one machine that can do both would save a bit of space and cable-swapping; unless someone has proof that the Hi-Filter in this VCR works the same as Dolby NR my plan is to keep the Panasonic in place and play most SP tapes on that, and use the RCA just for LP and EP tapes which likely don't have Dolby NR on them anyways. At least this way I'll have one less VCR in the setup (also have a D-VHS machine which also plays S-VHS, a multi-standard Hi-Fi VHS that I only use for PAL tapes, and of course a Beta, industrial model also with Hi-Fi and linear stereo which is extremely rare, some of Warner's early Beta Hi-Fi stereo tapes also had stereo linear tracks on them.)