On 7 feb, 16:35, "EpsilonRho" wrote:
My mother lives in a area where the cell-phone signal is very weak.
Typically I can get only one mark on the phone field strength meter. That
forces me to go outside the house in order to have a reasonable chance of
completing a call (of course only if the weather permits). I have only basic
understanding of antennas, so I am asking this forum if the following idea
is feasible.

I am planning to build (or buy) a 850 MHz Yagi antenna (14 dB gain) to be
installed on the outside and pointing towards the signal strongest
direction. The boosted signal would be transmitted through a balun and a low
loss 75 ohm coax cable to the inside of the house terminating to a 1/4
wavelength 75 ohm antenna stub. Is this feasible? Could I get perhaps a 10bB
signal boost inside the house by means of this arrangement?

TIA
Gene

Regarding passive repeater,

Only when you have a very strong signal outside (that means your house
must be a very good shield), your suggested arrangement will work. The
problem is in the path between your handheld and the quarter wave
antenna inside your house.

Just 3 ft away from your quarter wave antenna the propagation loss is
about 30 dB (at 850 MHz). Assuming about 3 dB cable loss, the overall
loss (with respect to the handheld outside) will be about 20 dB. So
this arrangement may give improvement only, within one meter of the
quarter wave antanna in case of a building loss of more then 26 dB.

Probably you need a repeater system or connect your handset to the
cable directly (via RF coupling or other means).

Best Regards,

Wim
PA3DJS

What I did was to buy a collinear antenna made for cell phones from Radio
Shack. On my cell phone there is a jack for an external antenna. My dad
has the same problem. What we do is plug in the new antenna which has a mag
mount base and set it on top of the refrigerator to produce an infinite
ground plane. Works like a charm.

You might think about this solution.

Dana - K6DLE
"Wimpie" wrote in message
ups.com...
On 7 feb, 16:35, "EpsilonRho" wrote:
My mother lives in a area where the cell-phone signal is very weak.
Typically I can get only one mark on the phone field strength meter. That
forces me to go outside the house in order to have a reasonable chance of
completing a call (of course only if the weather permits). I have only
basic
understanding of antennas, so I am asking this forum if the following
idea
is feasible.

I am planning to build (or buy) a 850 MHz Yagi antenna (14 dB gain) to be
installed on the outside and pointing towards the signal strongest
direction. The boosted signal would be transmitted through a balun and a
low
loss 75 ohm coax cable to the inside of the house terminating to a 1/4
wavelength 75 ohm antenna stub. Is this feasible? Could I get perhaps a
10bB
signal boost inside the house by means of this arrangement?

TIA
Gene

Regarding passive repeater,

Only when you have a very strong signal outside (that means your house
must be a very good shield), your suggested arrangement will work. The
problem is in the path between your handheld and the quarter wave
antenna inside your house.

Just 3 ft away from your quarter wave antenna the propagation loss is
about 30 dB (at 850 MHz). Assuming about 3 dB cable loss, the overall
loss (with respect to the handheld outside) will be about 20 dB. So
this arrangement may give improvement only, within one meter of the
quarter wave antanna in case of a building loss of more then 26 dB.

Probably you need a repeater system or connect your handset to the
cable directly (via RF coupling or other means).

Best Regards,

Wim
PA3DJS

On Wed, 7 Feb 2007 12:28:16 -0700, "K6DLE/7" wrote:

Yeppers! That's the ticket! There's No Need to re-invent the
wheel, besides, it'd take you longer, cost more, and more than likely
NOT get any better gain. Besides, it'd probably look like some sort
of an experimental home-brew nightmare, huh?

You can buy one of these nice, compact yagi's on eBay, or just do a
simple Google `Net scan to find all the different companies who offer
such monsters. I've even seen some neat little jobs all made on a
tight little printed circuit board! But be aware the price variation
is WIDE when it comes to things like this, and so are the assorys.
Don't get any more than what you really need, and keep in mind that
once it's in place, the phone, well it's rather a "Stationary" set-up
if you want to use it from then on. In short, you have to keep it
attached to that darn antenna for it to do you any good, right? In
light of that, maybe a standard cordless phone may be the better way
to do things instead. . . ?

Well, there's my two-bits on this subject. It all depends on how
much mobility you need, and how many loose $$ you have to spend on it.

73's
Fat Fred Ferrely
AKA, "FFF"

=)



What I did was to buy a collinear antenna made for cell phones from Radio
Shack. On my cell phone there is a jack for an external antenna. My dad
has the same problem. What we do is plug in the new antenna which has a mag
mount base and set it on top of the refrigerator to produce an infinite
ground plane. Works like a charm.

You might think about this solution.

Dana - K6DLE
"Wimpie" wrote in message
oups.com...
On 7 feb, 16:35, "EpsilonRho" wrote:
My mother lives in a area where the cell-phone signal is very weak.
Typically I can get only one mark on the phone field strength meter. That
forces me to go outside the house in order to have a reasonable chance of
completing a call (of course only if the weather permits). I have only
basic
understanding of antennas, so I am asking this forum if the following
idea
is feasible.

I am planning to build (or buy) a 850 MHz Yagi antenna (14 dB gain) to be
installed on the outside and pointing towards the signal strongest
direction. The boosted signal would be transmitted through a balun and a
low
loss 75 ohm coax cable to the inside of the house terminating to a 1/4
wavelength 75 ohm antenna stub. Is this feasible? Could I get perhaps a
10bB
signal boost inside the house by means of this arrangement?

TIA
Gene

Regarding passive repeater,

Only when you have a very strong signal outside (that means your house
must be a very good shield), your suggested arrangement will work. The
problem is in the path between your handheld and the quarter wave
antenna inside your house.

Just 3 ft away from your quarter wave antenna the propagation loss is
about 30 dB (at 850 MHz). Assuming about 3 dB cable loss, the overall
loss (with respect to the handheld outside) will be about 20 dB. So
this arrangement may give improvement only, within one meter of the
quarter wave antanna in case of a building loss of more then 26 dB.

Probably you need a repeater system or connect your handset to the
cable directly (via RF coupling or other means).

Best Regards,

Wim
PA3DJS