Yes i supplying 12vdc to the radio. I'll try to check the solder again. will watch the video and try to follow the troubleshoot it. De 9M2KLH

#qcx20mini #qcxmini #alignment

Voltages for IC10 (both A & B) should be about 1/2 the voltage you are supplying to the radio. Since you are seeing 6vdc on pins 1-2-3 & 5-6-7 I'm presuming you are supplying 12vdc to the radio? As Da

#qcx20mini #qcxmini #alignment

I was going to respond to this post but decided otherwise, perhaps someone else with less self control will decide to respond.

#qcx20mini #qcxmini #alignment

I am trying to follow this thread but it seems some wires are crossed somewhere 73s Ted

#qcx20mini #qcxmini #alignment

Greg, With respect, that's not the case. I'm a very experienced builder and my QCX-mini was built to a very high standard, IC9 on my board was faulty from the start. It's clear from the sheer number o

#qcx20mini #qcxmini #alignment

Since this is a new build and has never worked properly, by far the most likely cause of trouble is a construction fault of some kind. Although it is possible, it is not likely that a new component is

#qcx20mini #qcxmini #alignment

Those voltages are normal when using an external DVM. The voltages on the chart use the internal DVM. It has a lower input impedance and loads down some of the voltages to the indicated lower levels.

#qcx20mini #qcxmini #alignment

i manage to change C11&C12 but no luck. May i know is the IC with high voltage like what i highlight in below sheet normal? De 9M2KLH

#qcx20mini #qcxmini #alignment

That’s correct Ian. 73....Ron

#qcxmini

I noticed on the QCXmini PCB there are resistors labelled R244, R245, R246 and R247... but they are not shown on the circuit diagram nor in the parts list. Are these just 0 ohm resistors, i.e. a wire

#qcxmini

Hi Hans, No smoke (!), all calibration adjustments behaved exactly as documented, 4W out at 12V. It was a pleasure to build, and I can see some fun ahead! I cannot tell you how impressed I am. Thank y

#c38 #qcxmini #manual #mods #pcbversion

Is there a photo of your test jig in action on the QRPLabs website?

#c38 #qcxmini #manual #mods #pcbversion

You forgot to mention, also a different, more reliable, PCB Fab House. :) :) :) Great Service Hans !!! Thanks !!! Mont - km6wt

#c38 #qcxmini #manual #mods #pcbversion

Hi All :), WOW! I am impressed.

#c38 #qcxmini #manual #mods #pcbversion

Hi John Whatever smokes, it won't be that regulator :-D And remember, all Rev 2 boards have been through my super-duper test jig and passed its 21 tests. All 1,000 boards. Yes the test jig really did

#c38 #qcxmini #manual #mods #pcbversion

Hi Hans, that was quick! Thanks for getting back, saves me a fiddly job. Others reaching the same point may see this thread and know they can skip the mod. I've enjoyed the build, now girding my loins

#c38 #qcxmini #manual #mods #pcbversion

Hi John There is no need for the capacitor in Rev 2. No additional 10uF capacitor in Rev 2 (with the 78M05 regulator). I have not yet been able to update the manual. The only changes to the Rev 2 PCB

#c38 #qcxmini #manual #mods #pcbversion

Hello all, I've almost completed the build of a latest batch QCX-mini. I've followed the assembly instructions v1.05 (latest rev?) to the point where I should add the additional capacitor C38, but rea

#c38 #qcxmini #manual #mods #pcbversion

Hi A little more info from me that I'm cautiously optimistic will help diagnose and in due course cure this minor but niggling issue: After futile efforts on my part to detect the source of the "next

#qcxmini

Hi Jelle IC9 was also defective in my 20m qcx-mini kit. Very low audio in RX but otherwise ok. After replacement of IC9 the alignment could be finished and I have now very loud audio and about 5W outp

#help #opamp #qcxmini