On Mon, 15 Nov 2010 12:30:29 -0800, (Dave Platt)
wrote:

In article ,
mm wrote:

Not a repair question, so maybe this is OT, but...

Why do you suppose at solidstate.com, the Winegard MS 1000 antenna,
which doesn't include an amplifier, costs the same as the Winegard MS
2000 which does have a built-in amplifier 60 dollars. This is a
round omnidirectional antenna that looks like a flying saucer.

Thanks Bill and Jeff. I'll reply just here if it's okay.

The MSRP of the MS-2000 is $110, while the MSRP of the MS-1000 is $70.
SolidSignal is offering a much greater discount on the MS-2000 at the
moment.

I don't know why the MS-2000 is so heavily discounted... the commonest
reason for this is probably "We bought too many, we need to reduce our
stock, so let's blow them out at just barely above our cost."

Maybe. That would answer the question, which intrigued me
intellectually.

FWIW, the 2000 even includes 50 feet of cable that the one without the
amp doesn't include.

Does that mean the amp in the one with an amp is really cheap?

Does that in turn mean that one of the amps they sell for 50 or 60
dollars without an antenna is many times better?

Not necessarily. The antenna units themselves are the same diameter,
same height, and probably have very similar gain and directivity
patterns (i.e. not much and not much). They may even be identical
except for the labels printed on the outside.

Does that mean one should buy the one without the amp and then get a
separate amp if necessary?

Could be. However, you'd probably need to pay substantially more in
order to get a really high-quality amplifier.

Okay, that's still a possibility for later.

Actually, I just installed a RAdio Shack signal amp, that I found on
their discount table marked down from 55 to 8 dollars I thought it
might overload the signal, so I put a small tv in the attic just to
check this on at least one local network station that it was tuned to.
AFAICT it had no difference on that station, or when I got back to my
bedroom, any of the others.

It also has a pot that is supposed to lessen the amplification, but
that had no effect either. I told myself that my DVDR tuner overcomes
overloaded signals, but the marginal stations are probably no stronger
either, so I guess the thing is broken. Even though the green LED goes
on. It didn't look like a return, but maybe it was. (Because there
other sale stuff was more like 50% off.)

I suppose you guys would check this by connecting an oscilloscope to a
tv co-ax, and compare that with the output after the same co-ax input
goes through the amp. Should I do that? I have an old Heathkit or
was there EicoKit oscilloscope that I bought usedn and have never
managed to use much.

TV amplifiers are very much a mixed blessing. A mast-mounted amp can
help overcome the signal loss in the cable going down to the house,
and may enable you to use a passive splitter to divide the signal
among multiple TVs or DVRs or VCRs.

I was planning to do that as a next step, at least to tvs in two
upstairs rooms.

However, such amplifiers have
serious limitations:

- They don't do anything to help overcome the effects of multipath
reflections (i.e. the signal from the transmitter reaching your
antenna via several different paths, due to reflections off of
buildings and trees and planes and etc.). Multipath causes
ghosting on analog TV channels, and can cause abrupt signal
dropouts and "macroblocking" on digital TV channels. Since an amp
can't distinguish between the different signal echoes on a given
channel, it doesn't help matters.

- Amplifiers can be subject to strong-signal overload, which generates
internal distortion and can make the signal quality at the TV worse
than it would be without an amp. This can be an issue if you have
any sort of strong VHF or UHF transmitter in your area... a nearby
TV station tower, a ham radio operator, a police or fire station,
etc.

Somewhere I got an adjustable signal attenuator that I could put in
the antenna circuit.

- Amplifiers add their own noise to the signal.

Ugh.

A really high-quality TV amp will have bandpass and band-reject
filters tuned to allow only TV-band signals into the amplifying
electronics (filtering out unwanted signals before they saturate the
amp), will have a good low-noise, high-dynamic-range amplifying
transistor or chip, and will have only as much gain as you really need
to pull in the stations you're trying to boost.

There is a whole set of 5 stations in DC that have foreign country
broadcasts, that I can get late at night but not at all or just for a
second or two during the day. Plus another set of 4 stations I can
get sometimes. I was hoping to get these all the time. Plus the NBC
station in DC when Baltimore has some local sporting event on. Except
for NBC, I didn't even know about them before I got the antenna for
the attic (I can't more it to a pole or tower.)

Most cheap amps have little or no filtering, and a single MMIC
amplifier chip which may have too much noise, too little dynamic
range, or too much gain for your signal environment.

In general, I think you'd get the best results if you were to buy a
*directional* antenna, put it up high on a mast, and use a
remote-controlled rotator to aim it at the station you want to receive
at any given point in time.

I bought a fairly big directional antenna, put it as high as my
situation allows, and when I had a smaller rotating antenna, I soon
got tired of rotating it. In addtion to the current antenna, I was
considering the 2000 that started this thread, which is
omnidirectional and should improve reception for the local stations
that the big antenna doesn't point to.


If aiming isn't possible, and you have to use an omnidirectional
antenna such as these "flying saucer" types, I'd suggest mounting it
up in the clear (well away from trees), as high as you can manage
given your situation, *without* using an amplifier... and then see if
you get acceptable signal quality at your TV. If not, lower it and
add the amplifer (right below the antenna, not down at the TV!) and
see if this helps matters. If even this doesn't help, you'll need a
better antenna (one with directional gain) and a rotator.

I think you might as well buy the MS-2000... it's probably basically
the same antenna internally as the MS-1000, and you'll get the cable
and amplifier "for free" due to the current heavy discount on the
price.

Sounds good to me. If worst comes to worst, I can put an attenuator
in the co-ax to the tuner, or I can bypass the amp electrically.

FTR, I later noticed another flying saucer antenna that is directional
and rotates and has a memory of which direction it should point for
which station. Wow!!! But it's about 150 dollars. My browser is
jambed up right now or I'd tell you the name and model.