433 Mhz... with more power..

[henrik2000]

Thank you to all people who gave very interesting links.
Now any one wants to go over 100 metres ?

I am looking for 100 mW.. 1 Watt 433 MHz..

Any help in the right direction will be very appreciated.

Thank you in advance.

Regards

 

[ted]

Well, the first thought I had in my mind is that my old DEFA car alarm control worked several ten meters, with lousy antennas in both ends.

With a proper antenna you might get longer range even with small transmit effect. On 433 MHz the antenna dimensions are not any more huge, and getting a little extra gain should be relatively easy. There have been some antenna books in e-book collections recently.

Another thing is the sensitivity and, not least, the selectivity of your receiver. I noticed that the same car alarm controller did not perform well at all in some places with strong disturbing signals. (One horrible place was Toulon in France, where I had hard times to inactivate the alam even when pushing the remote on my windscreen. I wonder what kind of transmissions they have there - had no scanner with me on that trip.)

So, see both of these aspects and you might manage >100m with smaller power than 100mW. It saves batteries, too.

Ted

 

[henrik2000]

433 MHz with more power

Thank you Ted for your very valid comments.
I am trying to use "off the sleve" FSK transceiver, but they lack seriously of output power.
BTW I do not intend to open (or close) a garage door but to establish a short distance network..

Thank's again.

Regards

 

[koky]

You can use LPD rtx device, usually you can cover 500 mt (10mW), but with simply modify you can obtain 500 mW and cover 2 km.
The LPD rtx have a low cost, more of 30 channel.
The best way is an fsk modem for make a secure 1200 bps network

 

[VSWR]

Don't even think about raising the output RF power level above 10 mW!

We hams already have *BIG* problems of all these wireless stuff operating in the 70 cm amateur radio band.

Thank you to all people who gave very interesting links.
Now any one wants to go over 100 metres ?

I am looking for 100 mW.. 1 Watt 433 MHz..

Any help in the right direction will be very appreciated.

Thank you in advance.

Regards

 

[henrik2000]

thank you koky.. 400.. 440 MHz amplifier

Could you please comment the intended use of a MRF1517T1 giving about 7.. 8 Watts ? (See intended enclosed schematic)

(Or if you know better amp please let me know)

Thank you in advance

Best regards

 

[Trishool]

why this much power

henrik2000

By using 1 W power you will disobey government rule ??
anyway search atmel and you can find an amplifier to do that after the RF stage .


Ts

 

[henrik2000]

Re: why this much power

henrik2000

By using 1 W power you will disobey government rule ??
anyway search atmel and you can find an amplifier to do that after the RF stage .


Ts

Thank you for the info. governement rule.. ? Depends of the country or are the USA the ONLY one ?
:lol:

 

[FFFFFF]

6 * F

 

[Trishool]

Re: why this much power

henrik2000

Thank you for the info. governement rule.. ? Depends of the country or are the USA the ONLY one ?
:lol:

henrik2000:
:lol:

Not USA but in most of the areas where civilization is there ? I feel it wont
matter if you plan to come along with me to Himalayas ,Mount K2 8) .

Ts