New kit: QCX+ replacing the QCX

Hans Summers
 


Hi all,

9,937 QCX kits have been sold since the launch in August 2017. The current batch of kits are almost at an end. Despite the huge number of kits sold to date, the ongoing demand is still very strong. It became apparent to me that regardless of what other new kits come later, there will always be a place in many radio ham's hearts for a high performance, mono-band QRP CW transceiver kit. With its high performance, easy to build and use, CW decoder (including practice mode) and keyer, etc etc., the kit has also proven attractive to newcomers to amateur radio and/or CW. 

But I wanted to fix some of the things that have always nagged me at the back of my mind since the start. For the YOTA 2017 summercamp hosted by RSGB in UK, I was under such tight budgetary and time constraints that I had to compromise on certain things. Particularly the inconvenience of fitting the QCX into an enclosure due to the connectors on the two sides, with controls and LCD all at different heights. This has been a distinct disadvantage in many people's mind (though also unleashing much creativity among mechanically inclined constructors). 

QCX+ is the replacement for the QCX. No more QCX kits will be made. You can read about the QCX+ here http://qrp-labs.com/qcxp

The QCX+ development is complete, it is currently in production and will be shipping in mid-June. I am making this announcement now, to allow pre-orders, since the current batch of QCX kits is now practically finished. 

But:

QCX+ is the same circuit as QCX.
QCX+ runs the same firmware as QCX. 
QCX+ operates just like a QCX. 

The changes in QCX+ are as follows (summary, see http://qrp-labs.com/qcxp for full details):
  • Optional beautiful extruded aluminium enclosure
  • Much larger PCB. The PCB area is more than doubled. This permits a less dense component installation, following feedback from some constructors who found the QCX PCB rather densely populated. The main PCB is 13 x 10cm (compared to 8 x 10cm in QCX). 
  • Thicker PCB traces (at least 16mil, rather than 12mil in QCX)
  • Traditional front-panel arrangement: vertical front panel PCB holds LCD and controls, rear horizontal PCB has the main circuits. Pin-headers connect the two. 
  • Power on/off button on front panel
  • All connectors are on the rear PCB edge
  • Two additional 3.5mm stereo jack connectors for PTT (50W PA) and CAT control. 
  • 2.1mm barrel connector for power
  • 7805 bolts to rear panel for heatsinking
  • Three BS170 PA transistors and the MPS751 keying envelope transistor are now bolted flat on the PCB for heatsinking purposes - reducing probability of overheating
  • Lots of pin headers and test pads for debugging, extending, experimenting, modifying etc., including modifying the purpose of the rear panel 3.5mm jack connectors
  • Plenty of space for modifications and experiments
  • C24 increased to 470uF (quieter Tx/Rx transitions in full-QSK mode)
  • Incorporates IC3 pin 13-14 10K resistor mod http://www.qrp-labs.com/qcx/qcxmods/ptt.html
Due to the 2.2x increase in PCB area, additional inter-board connectors, switches, hardware etc., there is a modest increase in price from $49 to $55. 
The price of the optional enclosure kit is $25. The combination of QCX+ and QCX+ Enclosure is still cheaper than the combination of QCX and the most popular enclosure (BaMaTech aluminium enclosure). 

Manufacturing is already underway and PRE-ORDERING is now open, for shipment in mid-June 2020. See http://shop.qrp-labs.com/qcxp

Comments welcome

73 Hans G0UPL

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