J. Bradshaw J. Bradshaw" <ac6tk@cybertime.net
Tue, 3 Mar 1998 12:13:06 -0800


He should probably throw that radio shack amp as far as he can.
I have done several of these kind of installations in connection with CCTV
systems, and you have close attention to several things at once in order to
have a successful distribution system.  

Avoid becoming involved in your neighbors custom difficulty, or you surely
will be hated by him.  If you are already involved, Here is a step by step:

1).  Take ONE of his television sets to where the cable connects to his RS

2).  Disconnect everything else and connect the cable directly into the TV.
 If the problem is gone, YOU have no further problem.  

3).  IF there is insufficient signal for an EXCELLENT picture on all
channels, there is a cable problem that must be resolved before any more
amps, TVs, VCRs or anything else can be added to the system.  PERIOD.

4).  A typical distribution amplifier must have optimum signal to noise
ratio before elevating signal strength to the point that it will overcome
all of the splitter and cable losses, that can exceed 40 dB even in a well
engineered system that you described.  The only way to be sure of that is
to take signal strength measurements, calculate all of your losses,
rearranging where necessary to balance your losses to prevent starving one
location whole overloading another.  Also, the amp must amplify the whole
range of signals in the cable line-up so that the difference in cable and
splitter losses between 54 MHz and 400 MHz or even 900MHz do not also cause
overload at the low end and starvation at the high end.  
I have often run into people who see a big antenna, and proceed to get you
to fix their TV reception for them by complaining.  To be fair, they may be
desperate and have nowhere else to turn.  But know where to draw the line,
or you may find yourself inadvertently in a new hobby.

If that is now the case, I can sell you REAL distribution amplifiers,
splitters, tilt compensators, modulators etc.  

73, de Jim Bradshaw, ac6tk@cybertime.net

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