Path: utzoo!attcan!uunet!aplcen!uakari.primate.wisc.edu!zaphod.mps.ohio-state.edu!rpi!crdgw1!ge-dab!tarpit!ucf-cs!eola!freeman
From: freeman@eola.UCF.EDU
Newsgroups: sci.electronics
Subject: Re: Descramble Cable Using Filter?
Message-ID: <6900012@eola>
Date: 10 Jul 90 07:12:00 GMT
References: <3525@umbc3.UMBC.EDU>
Lines: 16
Nf-ID: #R:umbc3.UMBC.EDU:-352500:eola:6900012:000:735
Nf-From: eola.UCF.EDU!freeman    Jul 10 03:12:00 1990


About 10 years ago, our local cable Co. jammed HBO by putting a narrow
interference signal in the middle of the Channel 4 video. Picture was
wavy, audio was clean. They installed band-reject filters in your line
to remove (about 95% of) the noise if you paid for the service.

Anyway, we made some cheap "HBO Boxes" out of 300-ohm twin lead cable.
We'd simply cut the twin-lead to about 1/4 wavelength and hang it off
the VHF antenna input screws. If that got us close, we'd wrap aluminum
foil (a strip maybe 2 inches wide) around the twin-lead, and slide it
up and down to tune out the noise. For what we paid, it produced a
watchable picture. I think that was before spectrum analyzers were
invented. |^)

MarkJ
freeman@eola.ucf.edu