QCX-40 Working...Sort of...

Chuck Carpenter <w5usj@...>

Finished the assembly and started the tuning and adjustments.

Connect power -- No Smoke!
Adjusted contrast -- OK
Started at step 3.71
Did the "Select Band" step, OK
Pressed "Left Button", OK
Pressed "Long Press" and NADA...

Tried a few things like touching up solder joints and checking parts, no change.

I'd plugged in a straight key with mono plug. Was trying some things and noticed the DL was getting warm. (Output BS170s barely warm)
Pulled the key plug and keyed with the switch -- OK. Plugged in Paddle; both levers straight key. Checked the manual -- Straight is default mode!
Plugged in a straight key with a stereo plug; OK.

Not being able to adjust or change anything except frequency, here's the condition of the functions.

o Power off then on, comes up 7020. Easily adjusted/tuned to other frequencies
o Measured the output power - 3.5 W, looks "clean" with the small Hantek 2C42 O'scope.
o Rx sounds good: To my ear, noise level and sensitivity sound about the same as my FT-847
o Side tone is pleasant, a clean sine wave.
o Right button seems to do what its supposed to, a/b menus etc.
o Morse is decoded accurately both TX and RX, didn't like it when tuned to a pile-up though... ;-)

At this point, I could use the rig quite nicely to make QS. But missing the benefit of all the other features and functions, of course. Some serious trouble shooting in order to see what I did wrong with the left button circuits. If that's where the problem is anyway.

Here's some results from the RBN at 3.5 W output.

K2DB W5USJ 7055.1 CW CQ 10dB 14wpm 0939z 31 Oct
KM3T W5USJ 7055.0 CW CQ 4dB 14wpm 0938z 31 Oct
KM3T-2 W5USJ 7055.0 CW CQ 4dB 13wpm 0938z 31 Oct
K1TTT W5USJ 7055.0 CW CQ 2dB 14wpm 0938z 31 Oct
KO7SS W5USJ 7055.0 CW CQ 14dB 14wpm 0938z 31 Oct
VE6WZ W5USJ 7055.2 CW CQ 17dB 14wpm 0938z 31 Oct
W8WWV W5USJ 7057.0 CW CQ 20dB 13wpm 0937z 31 Oct
KO7SS W5USJ 7057.0 CW CQ 18dB 13wpm 0937z 31 Oct
VE6WZ W5USJ 7057.2 CW CQ 18dB 13wpm 0937z 31 Oct

Fun Stuff...

Chuck, W5USJ (ex K2OFN)
ARCI 5422, SKCC 19956
EM22cv, Rains Co., Texas

ajparent1/kb1gmx <kb1gmx@...>

Left button issues suggest R44 or the button as right button and rotary encoder
are on the same path (to MPU pin 26. Each button encodes as a different
voltage into an analog pin to reduce the number of pins needed.

So likely wrong part in R44 or button rotated 90 degrees or soldering issues.

If left works and long press is not working then it likely user error. Long press
is long and no bounces. The difference in how the button works is firmware
in the MPU and unlikely that tiny bit of could would fail and everything else

Please reply on the group, no private emails we as a group get to share info that way.

William Martin <cwfingertalker@...>


When I built mine one of the buttons was faulty. I replaced them both. As I recall it would not make contact.

Bill N7EU

Chuck Carpenter <w5usj@...>

That message was mis-sent to the wrong group.

Should have been to QCXlabs.io

The problem was found via a reply with links to previous messages.

Cleaned up some soldering and all is well, really nice Tcvr, having fun...

Chuck, W5USJ (ex K2OFN)
ARCI 5422, SKCC 19956
EM22cv, Rains Co., Texas