Hi and thank you ... The radio was just finshed I powered up and tested buttons ect. Then I bumped the cw key to check rf power I whent back to recieve for 3 or 4 min. the screen brighted up then shutdown. Thats why I was thinking it was the power regulation. I been tracing the radio and if I got it right, I have the 3.3 volts that I think power up the cpu I have a voltage regulator and thinking of running the 3.3 volt to see if it power up however I not sure location of vdd I think the 3 volts power the cpu up and the cpu powers up the rest of the radio.?
I hope this helps? Joe?
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Re: 50 Watt Power Amplifier - Low Power, High Harmonics
#50w
#50wpa
Poor vision on my part, and san-serif fonts, make for poor legibility for me. .? The gentleman who reported 42 MHZ coming out of his test on a 20 metre amp was Kilo Zero India Kilo Romeo, Ben.? His post with photos was 51637 from August 2020. He finally decided that he had a bad component in his low-pass filter section.
?
Bill
?
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Nicely built.
It looks so spacious compared to the QMX+!
You might consider adding the AGC board.
?
73, Mike KK7ER
?
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From all of my readings of blown BS170;s I have to say that Hans was brilliant to have a built-in set of fuses by using the BS170. When your little rig stops working because of too much voltage or poor antennas you have a great chance of finding the destroyed part quickly.? Using a stronger more resilient component may very well exceed the capability of other components downstream that causes you more frustration?
Now buying bad, mislabeled or misrepresented replacement components makes the BS170 look even more like the real culprit for sure.? Leaving the search for alternative components for when the original component is no longer manufactured OR it is a KNOWN design fault for an overwhelming number of units seems the prudent thing to do.
Amazon, eBay and Floor Sweepers, Inc. are probably NOT your best source of quality components, exceptions noted.
Of course, just my opinion.
John KK4ITX
for Zephyrhills Area Amateur Radio Club Many of life's failures are people who did not realize how close they were to success when they gave up. ? ? ? ?Thomas A. Edison? ? ?
On Thursday, May 22, 2025 at 07:38:47 PM EDT, Eugene Pressley via groups.io <me.e2p2@...> wrote:
Are their any drawbacks to using the alternate mosfets? Anything that needs to be altered to use them??
?
Eugene,
?
You might want to also consider ordering some TN0110 FETs, a BS170 alternative, to have on hand if you decide you'd like to experiment with a hardier device.
I'd also suggest order a few 5ft. rolls of Solder Wick and a ChipQuik SMD removal kit.
?
73 de WD4AH
|
I'm with Evan here.?
I'd never drill out a through-hole so I could insert a new diode.?
Nor would I use a push pin to try to (partially) clean out the hole.
Just clip the old diode or BS170 or whatever out and solder the new one to the stubs.
There is no need for the leads of the new part to go through the board.
?
Heating the board again and again to clean it with a solder sucker or solder wick is a fools errand.
The heat will compromise how well the pads adhere to the board.
If the pads get lifted off you then have?to figure out how to re-attach the broken traces.
Been there done that many times over a 45 yr career designing circuit boards.
?
The above is especially true for a multilayer board with internal traces and planes like the QMX.
A drill could easily cause shorts between internal layers near the hole.
Some parts such as BGA's (not found on the QMX) have pins (or balls) underneath the part,
and a single broken traces means throwing away a high value board since it can't be repaired
with a wire across the surface.? When dealing with RF or high speed clocks,? a patch wire
across the surface can behave much differently than the engineered trace through the board.
?
ChipQuik would work well enough when removing connectors and switches that must be
replaced with correct physical alignment,? or a heavy part that might break free due to vibration
unless it is properly mounted.? For a diode it's a waste of perfectly good ChipQuick.
?
Jerry, KE7ER
?
?
?
On Thu, May 22, 2025 at 06:59 PM, Evan Hand wrote:
The QMX series of radios uses a 6-layer PCB. Making the drilling hole larger could cause gaps in the internal layers. It would be better to use a thin lead and solder the fat lead above the board. Look at the board trace pictures and the schematics to verify that the connections are still there.
|
Re: Why no AGC for digital modes, as other modes?
? Re: Why no AGC for digital modes, as other modes?
From: ajparent1/kb1gmx
Date: Thu, 22 May 2025 21:27:50 EDT
My entire post that follows is from a self described obstinate and
ancient analog rf weenie:
It was said: "So a digi band has a couple of very strong signals it
tends
too make the weak ones impossible to detect."
..."It was a big problem with early receivers with a strong agc
system rather than large dynamic range." (that caused AGC pumping).
My immediate response is what is the minimum discernible signal
difference between single tone cw with selectable AGC and
sequential single tone FT8 without? What is to be gained, without
selectable AGC, by increased IMD and gain compression
with digital modes vs the use of AGC when operating cw?
I have read many a post, in other group postings, regarding what is,
to me, apparent fantasy regarding FT8.
I? await my comeuppance, as a relative digital ignoramus.
?
Though I differ, I thank you for your well stated and relevant
reason regarding your apparent choice of no AGC for single tone
modes.
Regarding my inquiry, it is far more relevant than "turn down the
volume".
Given the relatively large dynamic range of my ancient FT-990 and
TS-790A (and today's receivers? my QMX+?), and the?selectable
characteristics of AGC implementation, I have noticed no
undesirable effects regarding the use of AGC that effected the
receiver
?rf gain, whether I use cw or ft8/FT4 on hf, vhf, or uhf.
For my needs and desires, all I request is the ability to use AGC
as I choose, complete with a more pleasant listening environment
and an
AGC and S "meter" that works.
As far as I am concerned, the topic is closed.
Da Ol' Curmudgeon,
?????????????????????? ? ? ? ?? ??? wa4hei
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QMX+ firmware feature request
I'll start by saying I think if this as a "nice to have" change:
?
I use a manual antenna tuner and the built in SWR bridge is great for checking the state-of-tune. In a (my) "perfect world", the "Tune SWR" would present a full width, bottom line, bar graph of the VSWR, rather than a single number. It's hard (for me) to spin the tuning knobs looking a flickering numbers.
?
Just a thought.
?
Thank you Hans for producing such a great radio!
--
73,
Brent DeWitt, AB1LF
Milford, MA
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Re: Release of version 2.0 of ABS solution for QMX+ (Automatic internal antenna tuner, internal battery and internal speaker with audio amp)
#PSU
#QMXplus
#audio
#ABS
#ATU
Interested for a Europe group buy
Great work this addition to the QMX+, perhaps something to add to the shop.
--
73 de PE5ED / JO22
817 and QMX+
|
Thanks Greg. I will try that next time. I have tried to use low temp solder to help clear the ground connections but it did not work. I managed to use a push-pin and a very hot iron to open those up.
Tony
AD0VC
toggle quoted message
Show quoted text
I've successfully cleared holes with a hand pin vise and an assortment of really teeny drill bits. Start with an obviously too small bit and work up in size until the component just fits. Go slow, clear the swarf often.?
Successfully opened up many in QDXs, QMXs and 50Watt amps.?
Lately though, I bought some Chip Quick brand desolder braid. Just needed some more and decided to try theirs. Fabulous stuff! No extra flux needed and it really pulls solder away. I flow extra fresh solder on the hole in question and then apply the braid
and iron quickly. Tug the long end up a bit and hold while it flows up the braid. Works a treat as the Brits say.?
Greg KI4NVX?
On Fri, May 23, 2025 at 8:33 AM, mux_folder2001 via groups.io
<canthony15@...> wrote:
Thanks Hans. The hole diameter is good to know. I used my old dial micrometer, which is calibrated in inches, to measure a diode from the kit and then did a bad mental conversion to metric. Still, much smaller than a regular 1N400x. When you clear the holes
with a solder sucker, it leaves some solder still in the hole which has to be cleared out to get the fat diode leads in there.
73,
Tony
AD0VC
Hi Tony
I just measured one of the 1N4007 diodes from the kits, the wire diameter is 0.4mm. According to the PCB CAD program (I just checked) the footprint for these diodes specifies a 0.8mm drill size. So the holes ought to fit 0.7mm wire too.?
On Fri, May 23, 2025 at 5:07?AM mux_folder2001 via
<canthony15= [email protected]> wrote:
Nothing fancy on these connections. Top layer and bottom layer traces only. I just checked with the meter and all is well. My question really was about the diodes. Where do you get 1n4007 diodes with .3mm leads?
Tony
AD0VC
Tony,
?
The QMX series of radios uses a 6-layer PCB. Making the drilling hole larger could cause gaps in the internal layers. It would be better to use a thin lead and solder the fat lead above the board. Look at the board trace pictures and the schematics to
verify that the connections are still there.
?
73
Evan
AC9TU
|
I've successfully cleared holes with a hand pin vise and an assortment of really teeny drill bits. Start with an obviously too small bit and work up in size until the component just fits. Go slow, clear the swarf often.?
Successfully opened up many in QDXs, QMXs and 50Watt amps.?
Lately though, I bought some Chip Quick brand desolder braid. Just needed some more and decided to try theirs. Fabulous stuff! No extra flux needed and it really pulls solder away. I flow extra fresh solder on the hole in question and then apply the braid and iron quickly. Tug the long end up a bit and hold while it flows up the braid. Works a treat as the Brits say.?
On Fri, May 23, 2025 at 8:33 AM, mux_folder2001 via groups.io <canthony15@...> wrote:
Thanks Hans. The hole diameter is good to know. I used my old dial micrometer, which is calibrated in inches, to measure a diode from the kit and then did a bad mental conversion to metric. Still, much smaller than a regular 1N400x. When you clear the holes
with a solder sucker, it leaves some solder still in the hole which has to be cleared out to get the fat diode leads in there.
73,
Tony
AD0VC
Hi Tony
I just measured one of the 1N4007 diodes from the kits, the wire diameter is 0.4mm. According to the PCB CAD program (I just checked) the footprint for these diodes specifies a 0.8mm drill size. So the holes ought to fit 0.7mm wire too.?
On Fri, May 23, 2025 at 5:07?AM mux_folder2001 via
<canthony15= [email protected]> wrote:
Nothing fancy on these connections. Top layer and bottom layer traces only. I just checked with the meter and all is well. My question really was about the diodes. Where do you get 1n4007 diodes with .3mm leads?
Tony
AD0VC
Tony,
?
The QMX series of radios uses a 6-layer PCB. Making the drilling hole larger could cause gaps in the internal layers. It would be better to use a thin lead and solder the fat lead above the board. Look at the board trace pictures and the schematics to
verify that the connections are still there.
?
73
Evan
AC9TU
|
Re: OoT-RADIO HIFI TAMAGUCHI
You need to be careful, it's probably not legal to train an LLM on copyrighted books.
?
|
Thanks Hans. The hole diameter is good to know. I used my old dial micrometer, which is calibrated in inches, to measure a diode from the kit and then did a bad mental conversion to metric. Still, much smaller than a regular 1N400x. When you clear the holes
with a solder sucker, it leaves some solder still in the hole which has to be cleared out to get the fat diode leads in there.
73,
Tony
AD0VC
toggle quoted message
Show quoted text
Hi Tony
I just measured one of the 1N4007 diodes from the kits, the wire diameter is 0.4mm. According to the PCB CAD program (I just checked) the footprint for these diodes specifies a 0.8mm drill size. So the holes ought to fit 0.7mm wire too.?
On Fri, May 23, 2025 at 5:07?AM mux_folder2001 via
<canthony15= [email protected]> wrote:
Nothing fancy on these connections. Top layer and bottom layer traces only. I just checked with the meter and all is well. My question really was about the diodes. Where do you get 1n4007 diodes with .3mm leads?
Tony
AD0VC
Tony,
?
The QMX series of radios uses a 6-layer PCB. Making the drilling hole larger could cause gaps in the internal layers. It would be better to use a thin lead and solder the fat lead above the board. Look at the board trace pictures and the schematics to
verify that the connections are still there.
?
73
Evan
AC9TU
|
After a few days of work I completed my new QRP-Labs Xcvr after having built several years ago a Hi Band QDX.
It was a real pleasure, no surprise due to an excellent manual and the adjustement and alignment were done today without dificulty.
Next step will be to connect it to my Alexloop antenna.
To be sure the 6 aft connectors whould slide nicely into the holes of the back plate I had screwed this plate to the lower enclosure and slid the main PCB each time I added a connector to check its position before finishing to solder it.
The first difficulties I faced were to  fit the LCD module and the front panel PCB to the Front panel of the enclosure : I had to cut slightly the nylon nut close to the potentiometer and I could not put in place the other nylon nut close to the encoder, I just left it near the hole in order to keep the good distance between the LCD board and the front PCB.
The Last difficulties happened when I wanted to slid the main PCB inside the enclosure after having put in place the four 12MM spacers which hold the dev kit, the nylon screws below did not slide easily and I had to push quite strongly the PCB inside the enclosure.
WELL I'M HAPPY WITH THIS WONDERFUL KIT AND I'M GRATEFUL TO HANS FOR THIS NICE DESIGN.
|
Re: New QMX+ Calibration victim
Hi Stan,
Thanks, You were right. Lifting input legs of IC503 cleaned up the output from IC501/502. So new order to Mouser... :-)
Jonas,
It is very uncommon for IC501/IC502 to fail, but quite common for IC503 to fail with blown finals.
So I would first lift a leg of IC503 that connects to the output of IC501 or IC502, and make sure it is not some failure in IC503 that causes the IC501/IC502 outputs to look bad.? Failures in ICs can affect their inputs as well as their outputs.
Stan KC7XE_
|
Hi Tony
I just measured one of the 1N4007 diodes from the kits, the wire diameter is 0.4mm. According to the PCB CAD program (I just checked) the footprint for these diodes specifies a 0.8mm drill size. So the holes ought to fit 0.7mm wire too.?
On Fri, May 23, 2025 at 5:07?AM mux_folder2001 via <canthony15= [email protected]> wrote:
Nothing fancy on these connections. Top layer and bottom layer traces only. I just checked with the meter and all is well. My question really was about the diodes. Where do you get 1n4007 diodes with .3mm leads?
Tony
AD0VC
Tony,
?
The QMX series of radios uses a 6-layer PCB. Making the drilling hole larger could cause gaps in the internal layers. It would be better to use a thin lead and solder the fat lead above the board. Look at the board trace pictures and the schematics to
verify that the connections are still there.
?
73
Evan
AC9TU
|
QRP Labs kit shipping status
Hi all
Well I got back to Dayton and after some work to release my suitcases full of electronics, which were impounded by customs at our local airport, all is well. I have a large backlog of sleep and emails to catch up on, as well as the jet lag...?
Since the SSB firmware beta release at the end of March, sales volume doubled compared to the normal monthly average. The waiting list for assembled radios also doubled (see attached?chart which includes Dayton booth orders for assembled transceivers). Unfortunately I am informed by my colleagues that some kits have run out before the new batches?arrived. It takes several months to arrange manufacturing of a batch of 1,000 QMX or QMX+ kits, including component procurement from various parts of the planet, PCB manufacture and SMD assembly, preparing the kits of through-hole parts etc. It's a little difficult to judge the timing exactly.
So: - QMX: no stock. All through hole parts are either on hand, or on the way. The PCB assembly is completed and just pending shipment. All QMX kit and assembled radios orders are waiting for this new batch of QMX boards to arrive.?
- QLG3 GPS: no stock. There was an unexpected lead time on the E108 module but they were delivered yesterday. Now pending the SMD factory to assemble the boards, they will be shipped (along with lots of other board batches I ordered). Any QMX+ orders that include the QLG3 option are pending the arrival of the new batch of QLG3 boards.?
I updated the shipping status page:?
We have several other kits that are low on stock (including QMX+) but the new boards and parts are expected to arrive before the stock reaches zero.?
Thank you for your continued support.
|
Re: 50 Watt Power Amplifier - Low Power, High Harmonics
#50w
#50wpa
Probably time to work progressively through the amplifier path starting at the input and a hopefully clean input signal?
|
Re: 50 Watt Power Amplifier - Low Power, High Harmonics
#50w
#50wpa
On Fri, May 23, 2025, at 12:09 AM, <wtshyman@...> wrote:
I also found the discussion with KO1KR in August of 2020, but unfortunately I can't see his scope photos so I don't know if he had the same problem
Hi Bill,
?
Groups.io deletes photos posted directly into the post after a given time, which I believe is 30 days.? I save all of the original posts in my email archive to get around the deletion.? I searched that archive for KO1KR and found no posts for that callsign.? I also looked in QRZ and did not find a callsign.? Is that a typo?
?
It has been a few years since I played with the 50w amp.? I believe that I had to reduce the voltage to my QDX so as not to overdrive it, which does not explain the low power output.
?
If you can give me the message number, I can look up the photos you want.
?
73
Evan
AC9TU
|
Re: QMX+: low RX sensitifity @ 6m / 22 dB noise floor / 1500 Hz wistle
Hello Ken,
?
I am also skeptical about my cure and therefore I made several measurements to find sources of noise and constant tones of my QMX+.
?
In post #144992 I show the Lo signal @6m with strong sidebands (lines) around strong LO signal.
?
The LO signal was detetected connecting the BNC of QMX+ to a spectrum analyser (LibreVNA operating in spectrum-analyser mode, QMX+ in RX, DIGI mode)
LO signal is 12 kHz below RX frequency.
?
Another OM with same QMX problems verfied my obseraton (sidebands around LO signal) using a SDR RX and waterfall diagram.
?
After resoldering trifilar and handling PCB strong sidebands are gone but 1500 Hz tone remains, and I am happy QMX is working, but I am unhappy that I find no cause (QMX is working at lower bands).
?
In meantime I tried o understand detection technique of QMX (Tayloe detector)and to find a method to quantify signal strength of tones and make it reproduceable using wsjtx.
?
Measurements are on-going and I will post my results in next time.
?
@all: Can anyone with RX problems (high noise and addtional tones at higher bands) verify my observations of sidebands around LO signal?
???????????????? - Switch QMX in RX only mode, connect BNC to another RIG and observe spectrum 50 kHz around
???????????????? RX frequency (e.g. SDR and waterfall diagram).
??????????????? - Signal strength is between -40dBm - -130 dBm.
??????????????? - Please report additional signal strength in wsjtx (dB indicator at main page of program)
?
Vy 73 Michael
?
?
?
?
?
|
Re: Tune SWR on QMX+ always shows SWR <1.05
The release software now has a CAT command to read the SWR value, and extra virtual serial ports, so everything is there that is needed on the QMX side to make this happen - good luck, and let us know how it goes.
?
Cool! I was hoping there was a cat command like that - I suppose the most difficult thing would be for the esp32 to "host"/manage the serial connection, but it should be possible :)
?
?
?
?
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KK4ITX John
Brent DeWitt
Pierre - FK8IH
Bruce Akhurst