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Better signals for handy GSM 1800, please comment.
2

Better signals for handy GSM 1800, please comment.

Better signals for handy GSM 1800, please comment.

(OP)
Dear Friends,
First, sorry for my English, this is my first post and I have only a little knowhow/experience abt RF transmission.
Second, I have problem with handy signal inside my house is very weak sometimes no  signal at all, while outside I've got better (2-3 points of 5 full bar).
I have plan to try an Outdoor antenna unit using own made Dish reflector (D=800 mm, d=100 mm,f=400 mm) feed with 1850 MHz Helix, with coax cable 75 ohm transmitted to  Indoor simple Helix antenna .
My objective is to improve better receiving signals inside my house with this idea , but I'm not so sure

Friends, please comment WILL IT WORK ??

Thank You,
Regards

young dad

RE: Better signals for handy GSM 1800, please comment.

(OP)
Thanks to all,
Actually I have just finished the trial and it works great !
Dish dimension : D = 870 mm, d =130 mm, f = 363.9 mm so f/D = 0.42
Feed : Helix w/ d = 2", 4 turns 1.2 mm copper wire with copper foil imp matching.
Coax cable : RG58 Belden 9907 12 meters length, with BNC connector
Indoor aerial : copper wire 1.2 mm 1/2 wl + 3 turns d 13 mm + 1/4 wl, placed as close as possible to handset.

The result : I've got 4 bars GSM1800 signals with good stability inside my house.

The weakness : the indoor aerial should really close to the handset otherwise the signal will dropped dramatically.

Please inform : any links that I can learn how to make a simple and easy to build a 1850 MHz preamplifier + 1 or 2 W amplifiers ? so I can phone freely without bringing cables everywhere inside the house ?

Best regards,

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