Good news - we're open for limited services in Wembley. Ujima House is now actively under refurbishment and we'd love your help in making the space the best it can be.
During this interim period donations and continued membership are greatly appreciated while we transition to our new space.
| Alpha transceivers
Now also in stock at RS (RS Stock No. 666-6757) for £4.50 each if you buy 2 Clicky!.
Or £3 each if you buy 10 of the 868mhz (shorter aerial needed) version Clicky!.
If you get one of these, read the latest TRX documentation, as the TX and RX are slightly rearranged equivalents, but the TRX documentation is fuller.
This device appears to be the same or very similar: RFM12B, the links on that page includes a programming guide and a code library.
- Yup, the one on that page has a smaller oscillator, but the picture in the datasheet shows an identical device. We should test this library or this library. --Ms7821 09:04, 16 June 2010 (UTC)
These are the same devices as used in the CurrentCost range of energy monitors. The original manufacturer is Hope RF , but they have been rebranded by Maplin and RF Solutions. It would be easy to drive one using an Arduino or similar, and make it look like a CurrentCost sensor, or use it as a packet sniffer for CC devices.
They are single chips with an external crystal that communicate up to 300m using FSK at 433, 868 or 915MHz. Each device has a nominal frequency, but can be tuned to the other bands.
They have auto tuning, RSSI, and programmable gain, channel and sensitivity.
They are controllable through SPI, and provide a clock, interrupt pins and low battery indicator for use without an Arduino.
Getting the status register back (including RSSI) is easy. Getting the FIFO to work has not been achieved yet by us (but Das Labor have managed with little effort).
An Arduino comptiable library exists here, the author has developed a variety of accessories using these little radios. The library is very easy to use and has a built in packet structure and ACK ability. -- Confirmed as working Solexious 07:07, 7 March 2011 (UTC)
The Alpha modules (I assume all but know the 433mhz ones) from RS are the RFM12B modules which DO support different groups using the JeeLabs library. The RFM12 modules do not support this feature. --Islou 12:05, 24 April 2011 (UTC)