Gemini AD1700 Cable Converter
 

Picked this up - thought it would be neat to get some basic cable channels through the UHF tuner on my set in the bedroom. It works but there's loads of interference - not sure whether it's this box or a bad run of coax to the bedroom.

Anyone have prior experience with one of these?

Those are "upconverters" - we sold a model at the distributor I worked for in the 80's. They were all cheap - and yes, herringbone interference was the norm. Most folks bought them to put cable channels (read:MTV and Nickelodeon) on their kids' bedroom TVs without having to pay for another cable box. Setup was easy - put the set on UHF channel 58 and tune in channel 8 or 9 via the tuning cap on the bottom of the unit. Then, in about an hour, repeat the same step(s) because the dang thing would drift. I had a GE MB chassis console set with electronic tuning and had one connected - never could get the tuning system on the set to match up to the cable channels, so I used the upconverter and things went well. I had to put the upconverter as far from the set as possible to reduce (never did eliminate) the herringbone interference. FCC part 15 compliance my a**.

Nowadays, with 200+ channel NTSC tuners on sets, most sets will tune the bottom 90 or so cable channels and such an arrangement isn't necessary.

Cheers,

I have one of those kickin around here someplace. No use for it since we don't have cable out here...