It's been interesting this evening to look back through old photos. Here's a few photos of us
etching our first emonTx PCB ourselves using a laser printed transfer and horrible acid, not recommended!
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| Etching the first emonTx V0.1 in Jan 2011 |
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| First emonTx V0.1 prototype in Jan 2011 |
Needless to say they results were not great. Still, a fun experience.
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| emonTx V1 - May 2011 |
In 2011 we got our first emonTx V1 PCB manufactured, see introduction blog post. Only a few (about 10 in fact) of V1's were made, we sent most of them out for free to friends and developers. If you have one, it's a rare piece of hardware! We quickly moved to V2, tweaking a few things. The design did not really change huge amount to the V2.2 design which we're still selling in the shop.
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| emonTx V2 - March 2012 |
The emonTx V2.2 design which has been the backbone of the project for the last year and a half, in that time we've sold almost 5000 of these! They have been shipped all over the word from Hawaii to Korea and most places in between!
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| emonTx SMT prototype V? - Aug 2012 |
In the summer of 2012 we worked on an
emonTx SMT prototype, we threw all bells and whistles into this basing the design on an Atmel energy monitoring app note. This design was based on the ATmega32U4 and would be very accurate with adjustable gain pre-amps on the CT channels. However after building a first prototype (which worked!) we realised that the price of this unit would probably be more than most would be willing to part with for an energy monitor. Keeping in mind that a web-connected base station and LCD display would probably also be desired for a full monitoring system. We also realised that for our first intro into SMT manufacture this design with it's very extensive BOM was perhaps a little ambitious.
The first emonTx SMT design was shelved (at least for the time being) and we put our efforts into designing a simpler more streamline
unit with
performance on par with the emonTx V2 which is good enough for most energy monitoring applications. Here was born the emonTx V3:
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| emonTx V3 - Dec 2013 |
The emonTx V3 was designed to be easily SMT manufactured, fit nicely into a tidy wall mountable enclosure, be flexible in terms of RF and MCU and have some useful additional features such as the ability to power the unit from a single AC power adapter which also provides an AC signal for Real Power and Irms calculations.
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| emonTx V3 SMT pre-assembled |
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| The finished emonTx V3 unit |
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| Feeling like a proud parent as the first emonTx V3 is shipped...while also rocking a Movember! |
We're proud of where we have got to, however (as always!) there is still much work to do. Hardware wise we plan to make the emonGLCD pre-assembled SMT and (hopefully) reduce its cost in 2014 and also dip our toes into control of appliances as well as making system setup as easy as possible.
Thanks for your continued support along this journey. We would not have achieved half as has much if we were not standing on the shoulders of many other open-source projects and community contributions.
