Author Topic: new 40 mile transceiver for $185  (Read 1286 times)

0 Members and 1 Guest are viewing this topic.

Offline AdminTopic starter

  • Administrator
  • Supreme Robot
  • *****
  • Posts: 11,659
  • Helpful? 169
    • Society of Robots
new 40 mile transceiver for $185
« on: October 01, 2009, 09:49:54 AM »
People keep asking how to transmit data for insane long distances. So here you go, enough radiative power to probably make popcorn.

http://www.sparkfun.com/commerce/product_info.php?products_id=9411


Offline 4by4

  • Full Member
  • ***
  • Posts: 61
  • Helpful? 1
Re: new 40 mile transceiver for $185
« Reply #1 on: October 02, 2009, 11:02:02 AM »
It has 1 watt output, which is the FCC and ITU limit for the 900 MHz ISM band, but the ISM band also has an EIRP limit of 4 watts. For mobile apps, 4 watts is the strict limit. In the 2.4 GHz band there are exceptions for fixed links, not sure about 900 MHz. Of course there is no limit on the receive side antenna gain. You can get very high gain and 40-mile type ranges with a big parabolic and a fixed LOS link. For mobile links, an entirely different story, since high-gain horizontal-plane omni antennas have a lower practical limit to the gain you can achieve compared to the parabolics.

Offline 4by4

  • Full Member
  • ***
  • Posts: 61
  • Helpful? 1
Re: new 40 mile transceiver for $185
« Reply #2 on: October 02, 2009, 11:15:10 AM »
I should add, before some asshole starts quibbling with my statement, I am aware of exceptions. You can do high gain directional with mobile using tracking antennas, and you can do over the horizon using diffraction, ducting, meteor burst, etc. I worked for the US government, which routinely makes use of these.

Offline Spoil9

  • Robot Overlord
  • ****
  • Posts: 155
  • Helpful? 1
Re: new 40 mile transceiver for $185
« Reply #3 on: October 02, 2009, 05:11:46 PM »
I'm not going to argue with you, rather I'm going to say "wow"
Knowledge is Power. Power Corrupts. Study Hard. Be Evil.

 


Get Your Ad Here

data_list