[mythtv-users] Best place to insert a CATV amp

[Brian Wood]

On Jan 26, 2007, at 3:17 PM, Rudy Zijlstra wrote:

> Bill wrote:
>
>> Hello all,
>>
>> I cannot seem to find a good answer anywhere on this, so maybe  
>> someone here can help.
>>
>> Q:  In a line with several splits, where is the best place to add  
>> an amplifier?
>>
>> I just hooked up my newly recreated mythtv backend.  It has a  
>> PVR350 and a PVR500 in it.  At first I was getting pretty icky  
>> picture, so I hooked up a powered amp and it got better.  But not  
>> as good as it should.
>>
>> Pretty much my arangement is like so:  Sorry for it being  
>> confusing, but I am unsure how to portay it.  I've noted where I  
>> have considered putting it by inserting (option #).  I can also  
>> get an amp with multiple outputs which may be the way to go.
>>
>> I *believe* I have near perfect cable signal coming in (not too  
>> strong / not too weak) - but then again they did not seem to be  
>> the sharpest of people...
>>
>> -> STREET
>> -> RUNS TO HOUSE
>> -> 2 WAY SPLITTER -> TV | CABLE MODEM
>>
>> Cable Modem:
>> (ends here)
>>
>> TV: (Option 1)
>> -> 4 WAY SPLITTER
>>
>> 4 WAY SPLITTER:
>> -> TV
>> -> TV
>> -> TV
>> -> TV -> (Option 2) -> 3 WAY SPLITTER
>>
>> 3 WAY SPLITTER:
>> -> TV
>> -> PVR350
>> -> (Option 3) -> PVR500 (Which has a 2 WAY built in I believe)
>>
>> Basically the question comes down to is it better to boost the  
>> signal higher and let it drop down as it goes through, or let it  
>> drop down, then boost it.
>>
>> As I understand it, you get poor quality when it is too high or  
>> too low... so should I work out the drops so it always stays as  
>> close to the starting point?
>>
>>
>>
> If you put an 8dB amp before the 4-way it should work. If signal is  
> low
> at PVR at that point, you can still increase that 8dB to 16dB without
> problems.

Be careful about talking about signal level as if it were a single  
channel. When you state a level is that the highest or the lowest of  
the 50+ channels?, or an average? Is this the highest the cable  
company ever sends you or the lowest? The levels vary all over the  
place both in frequency and with time.

That's why I wanted to try and give at least a brief explanation,to  
show that talking about levels with a single number is meaningless.