sontag@control.rutgers.edu (Eduardo Sontag) (05/26/88)
Sorry for the elementary level of this question, especially if it had been asked before in this newsgroup...: I get at home a standard cable TV signal, which I'd like to split among various TV receivers. (Actually, the signal may also originate at my VCR, and goes through a switch box, but that's not relevant.) If I just use a splitter, the signal seems to be too weak. I bought an amplifier (10db, if I recall right) from Radio Shack some time ago, but that didn't seem to help much. Any suggestions? (The setup is such that the signal that comes into my house eventually gets split into about 6-8 coaxial cables, some going into TV's, other to the VCR, and some to outlets that I installed for future use.) (By the way, by "suggestions" I mean relative inexpensive off-the-shelf gadgets, or at least something that I could put together with little effort.) Thanks in advance, -eduardo d. sontag (sontag@fermat.rutgers.edu or sontag@pisces.bitnet) -- Eduardo D. Sontag, Professor Department of Mathematics Rutgers University New Brunswick, NJ 08903, USA (Phone: (201)932-3072; dept.: (201)932-2390) sontag@fermat.rutgers.edu ...!rutgers!fermat.rutgers.edu!sontag sontag@pisces.bitnet
wtm@neoucom.UUCP (Bill Mayhew) (05/27/88)
When connecting a bunch of TV sets to a cable system drop into your
house, first make sure that it is "legal" in your community. The
cable industry is changing billing standards, and not all
communities seem to have common regulations. In many areas, one
now pays a flat rate no matter how many TVs are attached. Where I
live, one is still expected to pay on a per set basis (yuck!).
We wouldn't want you to do anything illegal :-).
Anyway, now that that formality is dispensed with, to attach
multiple sets to the drop into your house, you can use an item
called a 17 dB tap. The taps are installed thus:
(tap) (tap) (tap) (tap)
cable drop----------+---------+----------+------ ... --+--terminator
| | | |
tv tv tv tv
The 17 dB tap is a 3 port device that splits the input in either
the right or left port to ~90% energy exiting the left or right
port and ~10% exiting the bottom port. The terminator on the right
side above can either be a 75 ohm resistor or a real load like a tv
set.
The system above works well because the signal level on the
distribution trunk stays relatively large, being reduced by only
about 10% for each tap it passes, thus all the tvs get about the
same signal level. The system can also be easily extended by
removing the termination and adding on more taps. Of course, if
the run is long enough, a line amplifier might be necessary.
There is an added advantage that the above system is relatively
insensitive to the vaggaries of disconnecting one of the sets at
the tap, as there is reletively little effect on impedance level
reflected at the input by the disconnection. Such systems are used
in hotels and appartments where joe random user might connect just
about anything to the antenna terminal in his/her appartment.
17 dB taps are available at most DECENT tv supply shops (not Radio
Shark, as far as I know). You might try mail order:
Edlie Electronics
2700 Hempstead Pike
Levittown, NY 11758
(516) 735-3330
There are, of course, lots of other places to buy such goodies.
--Bill
wtm@neoucom.UUCP