Posted by John in Detroit on 01/01/06 18:59

Roy L. Fuchs wrote:
> On 31 Dec 2005 21:18:41 -0800, "G-squared" <stratus46@yahoo.com> Gave
> us:
>
>
>>To make silly statements about the digital realm assumes you can
>>recover the analog to GET to the digital realm.
>
>
> Ever heard of "bit error rate"? Ever heard of "FEC"?

Yes, I have, and I'm sure he has, And have you ever gotten a digital
error message from your communications equipment which basically
translated to "Forget it, it won't work" Again, I have, MANY times.

Just off hand I'd be willing to say I have many more hours, Way many
more hours, of use of digital communications than you have.

This includes being online way before the 414's made the news, back so
far that I've actually got a 45.45 Baud Baudot teletype here in the
house (had two, scrapped one last year) I've been using digital computer
communications since the days of 300 baud Modems, back when 1200 was
considered "Fast". I've used digital voice communications, spent 10
years working with a digital communications system,,, Some rather
interesting error modes where the system was totaly unable to recover

NOT one bit of this, however, has to do with the need of a pre-amp on an
antenna... NOTE ONE BIT. Fact is that the rules for preamplification on
an antenna with a digital system are identical to the rules for analog.
Everythign that can be said about preamps on one applies to the other.

The only difference is the signal levels and noise levels which are
acceptable. to the system, note, the system includes the person
listening/watching. The major difference between digital and analog is this

Digital, either works or not, it is entierly up to the hardware and
air-path. Analog, what works for one person may well not for another,
since your mind's ability to filter "Signal" out of the "nosie" is part
of the equasion.

But if a pre-amp either A: Causes the downstream receiver to overload or
B:Is itself, subject to strong signal overload IT WILL MAKE IT WORSE.

If the noise figure for the pre-amp is worse than the noise figure for
the downstream receiver it may, or may not make things worse, depending
on the signal strength,

And finally, if the nosie figure for the pre-amp is better than the
noise figure for the downstream receiver (Which in the television world
is darn near always a given, in the world I live in it's not so certain)
and the signal is too weak for the downstream receiver to pick it up w/o
help... Then, and only then, will the pre-amp help, and that is also
when it's needed.

You speak of adjustable gain, or attenuators. Which can cure the
overload of the DOWNSTREAM receiver, however this does nothing to help
if the pre-amp itself is overloaded or has a bad noise figure

So the long and short of it is this.

Sometimes A preamp helps, Sometimes it hurts, and sometimes it makes no
difference. So, why pay for one if you don't need it?

If you dont' understand my e-dress. It says I've been working with
radio for nearly 40 years,

This thread is far too cross posted to continue, if you won't learn,
then it's your money that's going to be wasted. I'm done with you

Good by

--
John in Detroit E-Dress is smoked, try: w a 8 y x m at a r r l dot n e t

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