Updated Wiki Page: QMX External Microphone Options
#wiki-notice
|
Re: shorted PA on TX, dead SMPSU?
Dan, a high probability for a broken controller. Do you have a sharp tip for your DMM to probe voltage at a pin of the controller?
Driving 300 mA you may check voltage drop from Vdd connection to the mainbord to each of the five Vdd pins of the STM32. If high current is flowing into the STM32 you should see a drop of much more than 10 mV. Last proof would be to remove the STM32 and check resistance Vdd - GND.
?
73 Ludwig
?
|
Re: SWR and PWR does not show lcd
On Fri, Apr 4, 2025 at 05:05 PM, Stan Dye wrote:
If your power and SWR indicators are not working, please check that they are enabled in the menu.? If they are enabled, you may have a bad connection at T507 such that the processor can't read the power and swr.
The terminal Hardware Tests- Diagnostics can test transmit and show the Power and SWR.? If these read values for Power and SWR then T507 is fine.
|
Re: shorted PA on TX, dead SMPSU?
thanks again, Ludwig
?
CPU barely warmed at 200mA, and at 300mA I got a voltage drop to 2.5v and the CPU did warm slightly. I couldn't detect any other components warming.?
?
Is it game over?
Dan
?
?
|
Re: QMX and power bank PD
I received the cable and voltage monitor yesterday. Both appear to be good quality for the price paid. I should have the power bank by the end of next week.
?
Noticed though that the 25k one doesn't have PD. I mistakenly thought it did. It does output 12v 3a though so should be OK with the PD USB cable?
?
In half a mind to return it and get the 27.5k one with confirmed PD 3.1, though its �142 vs �99.
|
de minimis treatment "shall not be available" for China, quote from a Feb 25th US article from npr.?
It would not be a surprise if that were to be extended to other countries.?
Andy
--
The universe is made up of Protons, Neutrons, Electrons but contains only one M0RON.
|
Is this what you are looking for?
?
?
Hopefully this is the correct one as I ordered one a couple of days ago, after the earlier post ....
|
Re: ProgRock2 programming??
On 04/04/2025 22:07, Tom Smith via groups.io wrote: I measured the voltage on the HC6 socket and found negative .1 volts on one side and zero on the other. Tom, Hopefully that has not damaged the Progrock. But I'm fairly sure the output of the Progrock has a positive voltage on it. I suggest you try with a series capacitor, maybe 10n. Then no damage is likely. Of the two connections on the crystal socket one is used to inject the Progrock's output, maybe to the grid of a valve (tube). The series capacitor will be inserted here. The other one must be disconnected and supplied with your 5 volts for powering the Progrock. Did you do this? 73 Alan G4ZFQ
|
Moin Raijko,
?
Did you also experiment with a headset ? I would rather like to use a headset and As I understand the ones for Computers are too weak. By the way the Radtel one is not available actually and the alternative is more than 9 "Bucks".
--
Martin
DK3UW
|
Hello all
?
DX Commander stated in the last video that tarrifs will not apply to his antennas as it is below certain price limit. We will see if it is true and if it will also apply to Turkey.?
73
Pawe? SO8FM
?
P. S. I hope I can hear several SSB QMX stations during todays SP DX Contest.?
|
Re: QMX output is always 2W on all bands
On Fri, Apr 4, 2025 at 06:16 PM, Jeffrey W Moore wrote:
some of your screens show input voltage of 12.8v. ?Others show 11.8. ?Is that what you see there? ?Is the supply voltage being reported inconsistently or are you varying it?
Hi Jeff,
First of all, thank you for your reply — I really appreciate you taking the time to help!
In my previous post, I was experimenting with different input voltages using a bench power supply to see if the transmitter’s voltage and power would change accordingly. My theory was that the output power should increase at least somewhat linearly with the input voltage. However, regardless of the input voltage (ranging from 10.8V up to 12.8V), the output power changed only 0.4W.
|
Re: QMX+ SWR sweeps with SSB firmware?
Stan --
And it shows up when I am making my first attempts to transmit.
-- rec --
On Fri, Apr 4, 2025 at 07:31 AM, Roger E Critchlow Jr wrote:
I'm sure there's a reasonable explanation for all this
Roger,
This behavior could result from a cold solder joint in T507 or its associated circuitry.? Temperature can change its connectivity.
Stan
|
Re: #qmx #SSB Firmware beta 1_01_003 release
#qmx
#ssb
Hans,
?
I set the QMX to "practice" mode whenever I want to disable the transmitter and use the QMX as a receiver only in CW, DIGI or SSB mode.
This makes sense when I listen with a random non-resonant antenna and want to avoid transmitting in any mode, even the beacon.
Please maintain a simple way to disable the transmitter
?
73, Carol KP4MD
?
On Sat, Mar 22, 2025 at 04:35 AM, Hans Summers wrote:
1. Practice mode does not make sense in SSB I guess. When enabled in CW Keyer menu and SSB mode is selected it could be temporarily disabled and then when CW is selected again it could be automatically re-enabled.
?
I agree but I think this his already the case isn't it? Doesn't SSB ignore practice mode?
|
Thank you Paul and thank you George.
73! de Bekir TA2RX
5 Nis 2025 Cmt 05:12 tarihinde George Korper via <georgekorper= [email protected]> ?unu yazd?:
Hi Bekir,
?
With the supplied parts, and the circuits as designed,
as the frequency increases the output will diminish.?
So far I haven't seen a post that shows otherwise.?
?
73,
George
|
Hi Bekir,
?
With the supplied parts, and the circuits as designed,
as the frequency increases the output will diminish.?
So far I haven't seen a post that shows otherwise.?
?
73,
George
|
The setup I used is in the image below:
?
Power supply is from 3, 3400mAh 18650 Rechargeable Batteries in the
?
Microphone was made from a old earphone/mic PTT - seen in the front with silver button and hot glued foam windshield.? This tiny mic. works very well for what it is.
?
Also shown (on the right) is my Iambic key that I made and encased in figured wood :)? I prefer this to a duel paddle key, though it takes two hands to use.? I have a bulk supply of the components, including PCB, for the small VK3IL Pressure Paddle key if anyone is interested in it as a kit or complete.
?
This was connected up to my 160m EFHW!
?
Huge thank you to Hans for making the QMX even better!!!? As an old programmer I am in awe how Hans can make such a simple LCD interface and a few buttons work so well together.
?
?
Such great performance from such a small 'package'.
?
Myles ZL4MDX
|
I rather doubt that's true... If I understand, the differences in output between every unit have more to do with variations in the parts (the output transformer, toroids and associated caps of the filters, and possibly the BS170's).?
?
Paul -- AI7JR
On Apr 4, 2025, 18:17 -0700, ta2rx bekir via groups.io <ta2rx.bekir@...>, wrote:
I seem to remember reading a post that when powered with 9V, QMX+ will give a steady 5W output on all bands, but I cannot find that message now.
Is this true or is it my memory playing a game on me?
73!
de Bekir TA2RX
|
Re: QMX(+) Build experience, Poor Audio Filter Sweep/RF Filter Sweep/Image Sweep/ADC IQ test and resolution with new PCM1804
Karl, previously you wrote that "The signal is also present on pins 1&2 IC408 but not on pins 3,4, 12 thru 15"
Has this changed?? This is proper switching - the signal being seen on both parts of one coil,? but not the others.
?
?
?
|
I seem to remember reading a post that when powered with 9V, QMX+ will give a steady 5W output on all bands, but I cannot find that message now.
Is this true or is it my memory playing a game on me?
73! de Bekir TA2RX
|
Re: QMX output is always 2W on all bands
Hello Igor,
?
some of your screens show input voltage of 12.8v. ?Others show 11.8. ?Is that what you see there? ?Is the supply voltage being reported inconsistently or are you varying it?
?
also the bias should always be steady at 30ma. ?The QMX is actually reading a voltage which (if everything else is right) should correspond to bias current. ?So this is an indication that something downstream of the bias circuit is not right.
?
whenever I have a repair where the output is consistently too low, I get suspicious of T501 - the output transformer. ?
I think I would track down each of these anomalies thoroughly and separately.
?
let us know
--
73
Jeff Moore
W1NC
|
M0RON
Igor
Carol KP4MD
Paul - AI7JR