Thanks to Ali-Reza for reposting Dr. Dey's reply. If you are looking for lowest-cost short to medium range communications using ham radio, Android phones are not the answer. You still need VHF or UHF radio hardware. There are at least 20 radio manufacturers in China that make small variations on a common design of VHF transceiver, that can be bought for less than USD 50 each (often much less). Radio repeaters can be built using these same transceivers. There is also a huge surplus of transceivers in the US that have been made obsolete by the FCC's narrow band mandate, that you can buy for a few dollars, particularly interesting for higher power mobile radios. Shipping will be your major expense there unless you are able to do a freight container full at once. The biggest problem in most countries is almost always getting legal permission to use amateur radio for other public purposes. Solve that problem for your group, and find out what frequencies and power levels are permissible, and the technical issues are much easier. -- Too many emails? Unsubscribe, change to digest, or change password by emailing moderator at companys@stanford.edu or changing your settings at https://mailman.stanford.edu/mailman/listinfo/liberationtech ----- End forwarded message ----- -- Eugen* Leitl <a href="http://leitl.org">leitl</a> http://leitl.org ______________________________________________________________ ICBM: 48.07100, 11.36820 http://www.ativel.com http://postbiota.org 8B29F6BE: 099D 78BA 2FD3 B014 B08A 7779 75B0 2443 8B29 F6BE