[AReU] Digital TV and Modern Man

[Ron Youvan]

Bob Haynes wrote:

> The coax built into my motor home combines the cable TV and antenna 
> signals, and I have access to only one piece of 75 ohm TV coax which 
> used to run directly into the rear of the motor home's built-in analog TV

   You should be able to separate them if for no other reason but to NOT
broadcast the cable signal throughout the park.

> My television digital converter has no bypass.

> _Please let me know_ if it is OK to run signals from cable TV through a 
> digital converter.

   It won't hurt, but you should not get anything out of it unless the
cable company  (or are these "community antenna" systems?) sends out 8VSB
which I understand they don't.

> If it is OK to run cable TV through the digital converter, 
> please disregard the rest of this message.

   ?

> At the present time I have a barrel connector which I can put in between 
> the converter input and converter output coax cables. 
> This allows my TV to receive digital, analog, and cable signals.   

> I would like something nicer - it's a wife thing.

   We all fully understand this.

> _If I could find a coax switch to toggle between two inputs with one 
> output, that would be all I need._

> If there is no such coax switch:
> I may have to bypass my digital converter by throwing a coax "A-B" 
> switch which has one input and two outputs.

   Excuse me, a A-B switch IS a coax switch to toggle between two inputs.
Switches work either way, one signal feeding either of two loads and
One of two sources feeding one load.

> I could put the coax switch in the cable run ahead of the digital 
> converter, so the switch would send the incoming signal either to the 
> converter input or to the TV

   We discussed this, two switches or a splitter and one switch.

> Then I could use a coaxial combiner after the digital converter so that 
> the TV will either see a signal from cable TV or a signal from the 
> digital converter. 
> I can turn off the digital converter if it is not to be in service. 

> The combiners I have on hand are made with only one input and several 
> outputs. 
> What I need is two inputs and one output

   Excuse me, a coaxial combiner IS a coaxial splitter, they are the same thing.
Splitters work either way, one signal feeding two loads or two signals feeding
one load.  They are normally sold as "splitters."

> (1)        Is it a good idea to reverse the combiner I have and use two 
> outputs for the incoming signals with the combiner input going to my 
> analog TV?

   Yep.

> (2)        If the answer to Question 1 is YES, does it matter if my 
> combiner has a bunch of unused outputs?

   If it is a true hybrid splitter/combiner it matters little.

> (3)        - Or should I buy a combiner with one input and two outputs 
> and try to run it backwards? 

   A coaxial combiner IS a coaxial splitter.

> (4)        Or is the only good way to wire in my bypass to use a 
> combiner with two inputs and one output?

   Every way that works for you.

> (5)        If I need to buy a combiner or double coax switch, does 
> anybody want to tell me where to go?

   I am getting some ideas, but we are friends.

> Thanks in advance for your advice.
> If you know of a used combiner I can buy, please let me know.

   Try Goodwill, visit as often as you can, or go next door to Wally World,
for a new one.
   (don't blame me if they are out, I don't control their inventory)
-- 
    Ron  KA4INM - For perfect happiness, remember two things:
                  (1) Be content with what you've got. (2) Be sure you've got plenty.