Topics

QCX 20 off frequency

George Korper
 

Hi All,
I just assembled a second QCX 20. The first unit is working well and made contacts,etc.
The second unit transmits 2 KHZ up the band  and likewise receives 2 KHZ
down the band. I have checked for solder joints, etc. and the receiver works but
the second stage of alignment is not working well. This unit has the 1.01 firmware.
Need help before I troubleshoot without narrowing this down.
Thanks,
George

N3MNT
 

Check out the freq adjustment section of the manual on page 100.  That is where you would adjust it.

George Korper
 

I have reset to defaults. Is this an alignment issue? The problem is on transmit. 


On Fri, Nov 29, 2019, 3:00 PM Chopper <bob@...> wrote:
Check out the freq adjustment section of the manual on page 100.  That is where you would adjust it.

ajparent1/KB1GMX
 

Apparent problem is TX...

My first bet is RIT is enabled and so big value dialed in.


--
Please reply on list so we can share.
Off list email goes to trash, I had to due to scrapers.

James Daldry W4JED
 

Hi, George

Manual page 100, item 8.5. You have to adjust the 27 Mhz oscillator frequency. Change it a khz and see where you're at. A little math, and you can set it to 0 hz offset.

73

Jim W4JED


On 11/29/19 3:46 PM, George Korper wrote:
Hi All,
I just assembled a second QCX 20. The first unit is working well and made contacts,etc.
The second unit transmits 2 KHZ up the band  and likewise receives 2 KHZ
down the band. I have checked for solder joints, etc. and the receiver works but
the second stage of alignment is not working well. This unit has the 1.01 firmware.
Need help before I troubleshoot without narrowing this down.
Thanks,
George

George Korper
 

Thank you Jim and Allison, I have checked the RIT and it was O.00, and swapped out the firmware.
It was not the firmware. I did re-calibrate and set the crystal to 26,998. That worked.I have built three
kits and this one has been a little cranky. I switched solder and went up a little higher in wattage.
Big mistake, my old Weller was doing just fine.So I wonder have either of you seen crystals this low in freq. , because my two
previous kits were dead nuts at 27,004. Could the heat on my iron be too high and affected  the crystal?
I went from 25 to 45 watts.

SkipF, NT1G <skip.flem@...>
 

Soldering iron temp is only 'loosely' related to the power.
Just as replacing a 50 hp engine with a 100hp doesn't
mean your car will 'overspeed'. It 'could' but it shouldn't.
And I've never seen 'quartz' as sensitive to soldering as some
earlier solid state bonding/interconnect technology.

N3MNT
 

The alignment section on page 100 says the 27MHz crystals can vary slightly and the menu item is provided to correct for the variances.

Priyasloka Arya
 

N


On Sat, 30 Nov 2019, 02:16 George Korper, <georgekorper@...> wrote:
Hi All,
I just assembled a second QCX 20. The first unit is working well and made contacts,etc.
The second unit transmits 2 KHZ up the band  and likewise receives 2 KHZ
down the band. I have checked for solder joints, etc. and the receiver works but
the second stage of alignment is not working well. This unit has the 1.01 firmware.
Need help before I troubleshoot without narrowing this down.
Thanks,
George