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Hello QMX users,
this is not new to version 17, but was not of high importance (to me), so I did not mention earlier...
When recalling preset frequencies (e.g. you are on 20m and recall a frequency in the 80m band),
something goes wrong: No change in background noise, no reception on the intended frequency.
If you transmit, either the LPF filters seem to be set wrongly, or the frequency is far-off.
High current drain and no output power on 80m (and no SWR protection kicking in).?
When the QMX returns to RX, a persistent strange sound is heard.

In this state a regular band change (double-press on the volume knob) brings the QMX again to normal working order.

As I said, not that important (the QMX has great value as it is now), but did anyone else notice?

73 de oe1wyc+oe3wyc, Willy

?

Alan,

I would have expected an impact on all bands if there was an external short.? Since only 15 meters has the issue, it points me to the mux IC3.? The QDX has over a year of operation without issue, which is another pointer to an internal failure of IC3.? Still, it does not hurt to do a close inspection for a short on C28.

73
Evan
AC9TU

bearhawkpatrol,

Note that this is a QDX, not a QMX.? There is no display.

73
Evan
AC9TU

QMX?
Using 17 version (and others) of software, my 15 meter rf sweep produces strange results.

If I had to guess turning on the backlight for display is the problem,? I was thinking that maybe the higher current draw changes the freq of the power supply and creates resonance.

I have correct results leaving backlight off with RF sweeps? (15 meter band)

The RF sweeps for 20 10 11 12 meter never seem to have problem backlight on or off

The RF sweep with the? bands associated with 15 meter filters (17?)also mess up when backlight on but are ok with backlight off.


I would tune up coils with top boards off and be happy, and then assemble and RF sweep for 15 meter would be very bad.

Leaving backlight off is not a problem, it is just figuring out why it happens.

Has pin 11 been checked for a path to ground like a leaky C28?

before replacing anything try turning off display background.

I have found 15 meter lpf display to give good result when display off and screwed up when display on.

If i had to guess 15 meter is subject to the frequency of the power boards depending on load?

Timo,

I assume that you meant IC3 and not IC5.? I believe that IC3 has a problem.? The input for 15 meters is shorted, which is why you do not have a signal on 15 meters.? I suggest you replace IC3.? If there were a short on L12 then the other bands should be affected as well as 15 meters.

Note, IC5 is the driver for the transmitter.

73
Evan
AC9TU

Help! Qmx 2.0,12v,high band, vy low power on 17m/15mt 0.5watt,2 watts on 20 mtr, 1,5 w on 12/10mt,i rewind L512:10 turns and L508:9 turns, little better but low power, i put 2x 1n4007 (13.8 volts in power supply), measured with qrp dummy load, thank for next answer, Giovanni IT9XJJ.
P. S. controlled final mosfet..... are ok, no continuity between A, B, C and 7 pin of ic402.?

Evan, I check pin 11 on IC5 and it only outputs 0.852v on 15 meters.? So, that is the problem.? Rest of the pins per band outputs 2.450v as expected.? So does this tell you that the bandpass filter for 15 meters has a problem, or IC5 has a problem.
I checked C29 to C31 and they seem to be ok.? L12 also seem to be ok if I do the continuity tests to IC 3 pin 3-6. What is your view.
73 de ZR6TM
Timo

Hi Simon. Jusr FYI, there are no "default" settings for AGC yet. Meaning that if you only turn AGC on (in firmware 017) the settings are pretty much nil and won't do much if anything. For AGC to work at this time, you'll need to adjust the settings as well as enable it.?

I'm sure this will change over time, but this is how it is for AGC capability's first releaae.?

73?

Roy - KI0ER?

Sorry, gang!? I tried to find my posts and failed. So now this one.

May of you posted of bad connections on T507 and I finally checked mine out: the one that is directly hooked to the BNC antenna connector was good! There is a bad connection elsewhere on T507. This from simple ohm meter continuity checks. Today will devise a way to make those beautiful solder joints actually connect!

I will report here the results if I can find it!
--
73
Karl
KI4ZUQ

Hi

AGC is for CW and SSB

you'll need all the dynamic range to hear weak signals

In digi nodes it is better be off like NR (Hans NR? :) )

73 de muhsin TA1MHS

I did a quick test with a signal generator the other day (before the AGC was released) and I could hear a -120dBm (on some a -130dBm) signal on all bands.

73!
Simon

Thank you for all suggestions. 1st, I have firmware 014. 2nd, the dummy load is ruled out because the same thing happens through a wire dipole. Nano VNA used to check SWR which is well below 2 across 20m. I have now observed 2 different issues - sometimes the lock up happens as previously described, sometimes I still hear sidetone but the s-meter and DWR meter will stop showing any output. In reply as to why I wasn't using practice mode - I wanted to see if the s meter was working. And yes, the letter 'S' appears when lock up happens.

Sorry, I'm realizing those images might need more content to decipher. Sent left to right, the red (dit) and blue (dah) lines indicate when each paddle is being held down.

Here's a clearer example of the "R":


And how long I expect you should be able to hold the dah without a second appearing:

I have just ordered a audio mV meter and a few days later I think I can do a measurment.

Hello !

There has been some discussion here about ultimatic keying not working correctly on the QCX but I don't think it lead anywhere.? I'm noticing the same problem with my recently built QMX Rev2 running 1_00_017 so I did a bit of digging..

The issue seems to occur when squeezing both paddles. If the second paddle is not released before ~50% of the element is sent, you'll get a duplicate element.

Using "R" as an example: if the dah paddle is not released before the dah is about halfway through, you will end up with a bonus dah.? This is particularly obvious when you set the keyer speed down to 5wpm.? After your finger has left the dah paddle, you can hear the ending of your first dah and then the unintended second dah will play after.

The same thing happens the other way. You'll end up with an extra dit when trying to make a Y (-..--) or Q (--..-) by squeezing the?dah then tapping dit.

My expected behaviour (continuing with the "R" example) is that you should be able to hold the dah paddle until just before the final dit starts.


Are there any other users familiar with ultimatic who could chime in with their experience?

73 Shane

I get very strong clicks too. I enabled the agc and dont recall having changed any default settings. Happens in practice mode too, regardless of input voltage.

Another issue I found is band switching. I sometimes (often) end up changing mode to digi. This dramatically increases volume and hurts the ears.? I don't use digi modes, perhaps it could be optionally disabled altogether?

Thanks Hans for the great work!?
--
Simon VA2NM