Am 13.02.2018 07:53, schrieb Rick W via Groups.Io: Hello Rick, I don't think this requires a new controller chip! - All you need to do is setting the fuses correctly for the controller to work. I

I use an LM2577 boost circuit to get 13,8V from a LiPo pack. Just to be sure I put a ferrite ring on both the input and the output leads (as a common mode filter). I also decoupled the power to the

I have a QCX 20m running off a buck DC to DC converter , to reduce battery pack from 14 to 10v, with no issues in both CW and WSPR modes 73 Dave mmohvw

Hi, Not QCX But in my U3s I have two DC-DC boards inside the official case alongside my U3s and relay board. One runs at 5.5v and feeds the main board, which in turn feeds the gps, the other runs at

Thanks to all who have responded. I have found that I do indeed have a 20 MHz signal on pin 9/10 of the controller (apologies to all I must have miscounted). However, the symptoms have not

I tried using the Buck variable voltage device this morning with the view of stepping down my 13.8V bench supply to 9V to run the QCX-40mt on WSPR. The manual suggests that the 2 minute key-down in

A new chat has been created: Relocated L5 and LCD displays frequency 14,020,00 upon power on immediately. The bottom displays random letters. When I turn on the unit the calibration sound is

Howie, Quite a few have used them over on the BiTX forum to boost the PA RF out. (It has two power feeds, 12v to a majority of the electronics & a separate power feed to solely to the

Glad you are making progress. Alan

Progress! I had the volume pot wired backwards (remember I am using a QRP Labs enclosure and using a different smaller 5K pot not on the board.) When I turned the volume down the squeal went away.

Hi Howie, Someone has done that and mentioned in on the forum. I'm going to do the same with an adjustable DC to DC converter rated at 3 amps bought it from a local electronics shop. 73 Ray VE7AVG

QCX’ers, Are there any documented issues with the QCX Xcvr while utilizing a buck/boost circuit inline with your battery supply? Tnx de Howie WA3MCK

Hi Yanick, Glad it was just that, sometimes it takes a fresh suggestion to find the issue. Alan

Hi Rick, As the build was working OK before, Double check you still have 5v actually on Pin 7 and Pin 20 of IC3 the MCU, to perhaps discount one of the inductors having gone O/C in

nz0tham, What checks have you made to conclude R27 is faulty? Does it measure 'OK' end to end. Does the value change smoothly when you measure the wiper pin to one of the

Even a micro wire, too much current will snap it before the diode.

Well, I did the Schottky diode (however you pronounce it?) modification and my 20 meter CQX now starts mitout a second bump. Happy am I!

I have visually confirmed that all the components associated with IC8 and IC9 are correctly installed: R28-R35, R59 and R27 is 500 ohm. C13-C21, C39 and C53. All soldering looks good and there are no

Hi Alan, you’re right. That is my issue! I feel terrible, i should read the entire manual before asking questions. Thank you very much. Yanick 73, de VE2YCF

Bill, It might not come to that, the first section is about very carefully checking everything. Then checking again. It might be something around the R35 area (do IC voltages change?) but as Hans