is a device manufactured by  to provide a compact low-cost configurable clock generator with GPS sync option. It is was specifically designed to be used with the USRP, but nothing prevents you from using it with other device of your choice given it has external clock input.
ClockTamer is not only an open source aoftware project, but is also an open source hardware (OSHW) project. All schematics, the bill of materials and components placement are provided.
This project holds all source code you may need to work with ClockTamer and various instructions how to use and hack it.
ClockTamer may be used as a reference clock, e.g. for:
Questions and discussion should be directed to the ClockTamer mailing list.
2 Obtaining hardware
ClockTamer can be purchased from the Fairwaves web shop.
12 Dec 2012 Added instruction how to run GUI on Windows.
24 January 2011 Alpha version of ClockTamer control GUI is available. Check it out from our source repository. At this moment documentation is almost non-existent and we invite everyone to improve it!
09 January 2011 ClockTamer is now available for European buyers from []! US distribution is still in the works. If you need ClockTamer and you're not from Europe, you could get one from Olifantasia (they ship internationally) or contact contact us privately.
Other news is that we now have a [list] for the project.
04 October 2010 We very much appreciate all your interest in ClockTamer and it's not very easy to say this, but start of the sales is delayed again. A fab assembling ClockTamers failed to deliver our order on time again. We're working hard to sort this out and hope to get our ClockTamers next week, to make them available for sale in the next two-three weeks. I can't express how much frustrated we are with all these delays and how much we do want to get ClockTamers ready for sale as soon as possible. We appreciate your patience, please stay with us just a little bit longer
28 September 2010 Update about ClockTamer production. PCB fab succeed in manufacturing our PCBs only from 3rd attempt, and so we have 3 weeks of delay. Tentative estimate is that we'll have ClockTamers available for sale at the end of Oct. Stay tunned!
5 August 2010
ClockTamer becomes a great helper for security research! Chris Paget used ClockTamer during his BlackHat and Defcon talks about cellphone spying and extreme-range RFID reading (this fact is mentioned in the slides).
Answering a popular question: we don't have any ClockTamers in stock right now. We estimate to finish production run at the end of September and stock them soon after that. Look for the news for more information. You could also drop us an e-mail and we'll notify you when ClockTamers become available.
11 July 2010 Technical parameters of ClockTamer-1.1 and ClockTamer-1.2 including schematics, PCB layout and bill of materials are available.
20 June 2010 Here is a picture of ClockTamer-1.1beta. A small hardware patch you may see on the picture near the USB connector is what makes it "beta" (patch doesn't affect performance, though).
It's smaller then !ClockTamer-1.0, because we removed useless COM-port connector and few other unused elements. Now it's 35x86mm.
17 June 2010 We've measured the phase noise figure of ClockTamer-1.2 (the final version).
3 May 2010 We've created a small Dev-kit to simplify re-flashing and debugging of ClockTamer firmware. With this you don't need to solder anything and you can easily connect your programmer to ClockTamer. We're about to start selling this kits for $35 - write us if you want one. Schematics of the Dev-kit will be published as usual.
1 May 2010 Production of ClockTamer-1.1 is approaching. We've received beta-samples of ClockTamer-1.1 PCBs from the fab and tests show they're functional. Mass-production of ClockTamer-1.1 is about to start soon!
25 February 2010 We finally managed to publish schematics and component placement for ClockTamer-1.0. Right now it contains component placement only for the top side and miss bill of materials. We're working on fixing this.
- Features and specifications.
- Connecting ClockTamer to USRP.
- Calibration HOWTO.
- GUI manual.
- Control protocol.
- Using ClockTamer with GPS.
- How to build and flash ClockTamer under Linux.
- Description of ClockTamer SPI protocol and USRP connector pinout.
- Implementation of the GPS lock.
All project source code is licensed under LGPL license.
Schematics and their derivatives are licensed under Creative Commons Attribution-Share Alike 3.0 license (CC-BY-SA).
Host part of the project is licensed under New BSD license.
We apologise for mixing all these licenses in a single project, but we see this way as being the most appropriate.