[help] Only noise being seen while IQ balance / phase lo / phase hi.

Jose Tent

Hi. I'm pretty new to electronics.  I bought QCX not only to get on 40m CW, but to learn how this thing is working. I'd appreciate anyones' help as I'm at wit ends to get my QCX working.  

I was able to align the BPF at 8.xxx , but I'm not getting any thing but noise trying to align IQ balance / phase lo / phase hi.  My measurement for those are just bars jumping around randomly with "0" on the top right of the LCD.  I suspect I'm not getting any input from I nor the Q channels to adjust. 

So far, I tested with my mutimeter: 
-Proper soldering/connection of 4 windings for T1. 
-Proper soldering/connection of 4 other toroids. 
-Checked voltage 
    junction of R1 and R2. 2.5V 
   test pins 7 and 9 of IC4, 2.5V
   Pins 2,3,5,6 IC5 around 2.5
-Volume pots are soldered well and have good connections.
-Checked my soldering and for any shorts.   Can't find any problems.

Couple of symptoms observations: 
-LCD screens, center knob, and buttons seem to work fine. 
-I was able to aligning the BPF at 8.xxxx.  But, I noted that volume know doesn't work in a linear fashion.  The tone volume increases exponentially.  That is, the volume goes from zero to 100 some where in the middle really fast.   (normal ?? not sure) 
-Going in to  IQ balance / phase lo / phase hi menu item, I do not hear any tone.  Even with the volume turned all the way up. 

As a next steps, I'm going to check my voltage at various places indicated in the manual to trouble shoot further.   That's quite a list show in the manual, so that should take me most of the time I have tomorrow. I'm not past getting a cheap oscilloscope to troubleshoot this thing.  I think that might be kind of fun, if I wasn't so frustrated.  

Having said all of the above, If you have any guidance or advise on any direction I should look at, I surely would appreciate it. 

P.S. This is a QCX 1.05 purchased  May 22nd.  (Probably one of the last batch before it went to QCX+)

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