300 ohn to 75 ohm connection.
 

I had a new antenna installed on my roof by an electrician. The
antenna had a connection for ribbon cable (300 ohm). When I went to
throw the antenna box away, I noticed the 300-ohm to 75-ohm connection
was still in the box. So I took out a pair of binoculars and looked at
the antenna. The electricians had stripped back the last 4 inches of
the 75-ohm cable and simply screwed the two wires to the antenna
connection.

I am not too happy with my reception so I'm wondering if this could be
the problem.

300 ohn to 75 ohm connection.
 

Big time wrong, you will get much inferior reception without the balun
installed!!!
(balun - balenced/unbalenced adapter 75ohm unbalenced 300ohm balenced)

--
Michael Walraven
If it looks like a duck,walks like a duck, and quacks
like a duck it probably tastes like chicken.


"NadCixelsyd" wrote in message
ps.com...
I had a new antenna installed on my roof by an electrician. The
antenna had a connection for ribbon cable (300 ohm). When I went to
throw the antenna box away, I noticed the 300-ohm to 75-ohm connection
was still in the box. So I took out a pair of binoculars and looked at
the antenna. The electricians had stripped back the last 4 inches of
the 75-ohm cable and simply screwed the two wires to the antenna
connection.

I am not too happy with my reception so I'm wondering if this could be
the problem.

300 ohn to 75 ohm connection.
 

NadCixelsyd wrote:
I had a new antenna installed on my roof by an electrician. The
antenna had a connection for ribbon cable (300 ohm). When I went to
throw the antenna box away, I noticed the 300-ohm to 75-ohm connection
was still in the box. So I took out a pair of binoculars and looked at
the antenna. The electricians had stripped back the last 4 inches of
the 75-ohm cable and simply screwed the two wires to the antenna
connection.

I am not too happy with my reception so I'm wondering if this could be
the problem.


Definitely could be a problem. Definitely the wrong way to connect an
antenna. Definitely needs to be done properly.

But, may not be the only problem with your reception.

300 ohn to 75 ohm connection.
 

you must have the 300ohm to 75 ohm balum at the antenna

Lew
N4HRA
"wbertram" wrote in message
...

NadCixelsyd wrote:
I had a new antenna installed on my roof by an electrician. The
antenna had a connection for ribbon cable (300 ohm). When I went to
throw the antenna box away, I noticed the 300-ohm to 75-ohm connection
was still in the box. So I took out a pair of binoculars and looked at
the antenna. The electricians had stripped back the last 4 inches of
the 75-ohm cable and simply screwed the two wires to the antenna
connection.

I am not too happy with my reception so I'm wondering if this could be
the problem.


Definitely could be a problem. Definitely the wrong way to connect an
antenna. Definitely needs to be done properly.

But, may not be the only problem with your reception.

300 ohn to 75 ohm connection.
 

NadCixelsyd wrote:
I had a new antenna installed on my roof by an electrician. The
antenna had a connection for ribbon cable (300 ohm). When I went to
throw the antenna box away, I noticed the 300-ohm to 75-ohm connection
was still in the box. So I took out a pair of binoculars and looked at
the antenna. The electricians had stripped back the last 4 inches of
the 75-ohm cable and simply screwed the two wires to the antenna
connection.

I am not too happy with my reception so I'm wondering if this could be
the problem.

For no reason I know, most TV antennas are still manufactured for 300
ohm feedline. Without the 300 - 75 ohm balun in place, there will be
some loss due to the impedance mismatch, which is probably higher than
the loss you'd get through the balun itself. There is also a chance of
rainwater contaminating your cable. Your installers should not be doing
what they are doing for a living, and should consider something less
technical.

300 ohn to 75 ohm connection.
 

On 27 Dec 2006 12:13:37 -0800, "NadCixelsyd"
wrote:

I had a new antenna installed on my roof by an electrician. The
antenna had a connection for ribbon cable (300 ohm). When I went to
throw the antenna box away, I noticed the 300-ohm to 75-ohm connection
was still in the box. So I took out a pair of binoculars and looked at
the antenna. The electricians had stripped back the last 4 inches of
the 75-ohm cable and simply screwed the two wires to the antenna
connection.

I am not too happy with my reception so I'm wondering if this could be
the problem.

It certainly is contributing to it.
First is the unbalanced coax connected to a balanced antenna. That
effectively grounds the one element which should not be grounded. This
distorts the antenna pattern. So grounding the one element, connecting
a balanced antenna to an unbalanced feed line, and the impedance
mismatch could result in considerable loss in signal with the
resulting degradation in quality.

Second, without the 300:75 ohm balun you have a standing wave on the
feed line. This not only produces additional loss, but can produce
ghosts as well.

Third, the method of connecting can allow water into the feed line
which can cause rapid deterioration of the feed line resulting in an
ever increasing loss of signal.

Additionally if you are in a strong signal area, be it AM or FM
broadcast or TV this type of connection might actually generate
signals that would interfere with near by receivers. Poor connections
and frayed wires/shield can rectify signals and appear like a
detector, or mixer generating all kinds of *stuff*

With the quality of workmanship on top I'd also be concerned as to
what they used for connectors at the receiver. Also of import is
whether you have any splitters or amplifiers in the line. These
connections need to be properly made. This also raises the question
as to what they used for coax and connectors. Did they even use good
quality 75 Ohm coax?

Bluntly put, the guys you hired had no idea as to what they were
doing. Typically if you are going to hire some one to install an
antenna it would be an antenna installer, although they may be
difficult to find now days.
Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

300 ohn to 75 ohm connection.
 

Roger wrote:
Typically if you are going to hire some one to install an
antenna it would be an antenna installer, although they may be
difficult to find now days.

Thou hitteth thy naileth directly on the head.

These guys install cable systems all the time. They buy coax by the
mile. They remove antennas all the time. They couldn't remember the
last time they installed an antenna.

It's a pity more people are not OTA. When I saw that OTA was noticably
better quality, I dumped cable. $70 per month is precious for the 10
or so extra stations that I ever watched.