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Sunday, 27 May 2018

uBITX revised.

When HF Signals marketed the uBITX early December 2017, customers leapt in and ripped them off the shelf. Who could imagine the small Test facility in India that VU2ESE had setup trying to cope with the unexpected demand, or the women having to wind and test the toroids, churning them out at speed without breaking a finger nail. Even one type of toroid used had to be substituted, for another, as the world ran out and they couldn't be sourced easily, but still the uBITX production somehow was kept on track. A total to date of over 6000 uBITX PCBs sold, with very few bugs reported, apart from one batch with the faulty WX branded TDA2822 audio amp that hit the fan and must of caused an awful headache at the time.

Now that manufacturing has now caught up with demand, and there is no time lag on ordering, the uBITX becomes ex stock along with some new modifications and a new revised r4 PCB.

Could the uBITX get any better well certainly it looks like it does!


Here are the changes from Ashhar Farhan reported today on Groups.io:


1. A new, low distortion audio amplifier made from discrete transistors. This is one is optimized for head-phones and connecting to PCs for digital modes. It does work with the small speakers as well. Builders with the earlier versions can try this audio amplifier as an outboard amplifier.
2. The audio thump issue during T/R switching has been fixed.
3. At 28 Mhz, the output is about 4 watts. (this involves a single capacitor change from the earlier PCB).
4. I have included some 'jump' points to add interesting stuff like CW filters to the board. There are a large number of test points to help you debug and understand the board. 


All in all, the changes are 'backward compatible' . That is, you can hack these changes to the previous boards to get in the new functionality. I have updated the circuit diargrams on www.hfsignals.com
The earlier board's circuit diagram has moved to http://www.hfsignals.com/index.php/ubitx-r3-archived/

The bad news is that we had to bump up the price of the board by 20 dollars. We fought long and hard to keep the price down. My personal ambition was to keep the price inside (or at) $100. This is price rise has to do with three things : The recent changes in the Indian import duty and sales tax; Our own increasing costs to preorder the parts. Lastly, we also increased our payout to those who wind the coils, assemble and test the boards. They were working at the same rate for the last two years. It was about time. 

The new boards cost $129 USD with shipping. $139 USB with DHL option. 

The good news is that from now on, these boards will be available on order. The waiting queue is gone.

On a personal note, I am happy with the new audio. It is so much sweeter and cleaner on the headphones.  Far less fatigue after hours of CW work. I am also using the FT8 extensively, I have bagged almost twenty countries, testing the new firmware.