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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

 

On Tue, Apr 8, 2025 at 04:09 PM, Rey Machado wrote:
@ZL1REY Count me in for the ZL group buy


Re: #qmx #Firmware release 1_02_000 #qmx #firmware

 

I have started using fw 1.02.000 to do some FT8 via WSJTx. Works but:? 1) sound card out to WSJTx input is a bit low, reads in the 20 to 30 range (on WSJTx) when normal range is about 40 to 60 and there is no sound card rx out level adjustment that I could find in the radio.? 2) The WSJTx Mode settings need to be worked over some. Data/Pkt puts radio in Digi, but does not allow tx. USB puts radio in USB, but does not output rx. None works, but you have to set the radio for Digi and Digi never shows any rx level on the radio LCD. Don't know whether this (item 2) needs Hamlib driver, or radio fw, work to fix. I am using latest Hamlib 4.7 (64 bit).


Re: 3 cell lipo battery, how to use it anyway

 

Realistically, I'm hoping they could do a couple hundred Watts out at up to 14 mhz.
It's a very small package.
Hard to dissipate switching losses.
?
Jerry, KE7ER
?
On Sun, May 25, 2025 at 03:51 PM, Jerry Gaffke wrote:

Anyways, I was hoping you might ask some questions about that $0.04 GanFET
in the other thread.? Near as I can tell, two of those should make?
a dandy legal limit amp.? Probably? fine at 4mhz, but cooling
those suckers at 30mhz might be an issue.


Re: New QMX - observations and best QSO

 

Many if not all cell phones have an ESD shunting inductor right across their antenna input, either a choke or incorporated as a tuning element.
All of the properly-designed tube amps I've run across have a choke across the output to ground to avoid a DC blocking capacitor failure putting anode voltage on the antenna.? Ouch.
?
73, Don N2VGU


Re: QDX Low Receive but Xmit fine

 

In the Terminal program.... Audio gain for each band configuration.?
"Audio gain (dB): 54 is the default. Valid values for the parameter are 0 to 99. This makes it easy
to choose a gain by band - which is often useful to get WSJT-X and JS8Call perfectly happy on
each band without needing to manually fiddle with gain adjustments when changing bands. WSJTQMX operating manual; firmware 1_00_009 57
X and JS8Call documentation recommends when the band is empty, the signal strength meter on
the bottom left should be at about +30dB."


Re: 3 cell lipo battery, how to use it anyway

 

Allison,
?
This business of giving the charge rate in Amps as a fraction of C
which is a measure of battery Amp-Hours is just wrong.
The units don't agree!
I assume the convention was introduced by somebody that flunked physics.
?
Anyways, I was hoping you might ask some questions about that $0.04 GanFET
in the other thread.? Near as I can tell, two of those should make?
a dandy legal limit amp.? Probably? fine at 4mhz, but cooling
those suckers at 30mhz might be an issue.
?
Jerry, KE7ER
?
?
On Sun, May 25, 2025 at 03:21 PM, ajparent1/kb1gmx wrote:

We need the people that don't know to ask questions as then they read it.
?
>>Some may not know what you mean by "I charge them at .4C".
This tells us the rate you charge your battery in Amps, where 1C theoretically is the rate
at which a discharged battery will fully charge in one hour.??
?
C is the battery capacity.? Rare is it to charge at 1C for my LG cells that?
would make them very hot!? Often I charge at 8 or 10hour rate as it generally safer.


Re: QDX Low Receive but Xmit fine

 

In receive that is.


Re: QDX Low Receive but Xmit fine

 

Try going into Band Configuration and raise up the default gain (per chan settings) from 54.? I use 70 on some bands. That also increases the audio output.


Re: 3 cell lipo battery, how to use it anyway

 

Jerry,
?
We need the people that don't know to ask questions as then they read it.
?
>>Some may not know what you mean by "I charge them at .4C".
This tells us the rate you charge your battery in Amps, where 1C theoretically is the rate
at which a discharged battery will fully charge in one hour.??
?
C is the battery capacity.? Rare is it to charge at 1C for my LG cells that?
would make them very hot!? Often I charge at 8 or 10hour rate as it generally safer.
?
>>You said:? "Li tech can generally dump very large currents into a short?or worse overheat
and go into runaway ( creates a conflagration) resulting in fire."
LiPo chemistry can run away on you, LiFePO4 pretty much never does and is much safer.
Both can dump out some incredibly large currents when shorted, but then so can lead acid.
Have never had an accident with Lithium and have used a lot of it.
?
Neither have I.? But I worked with an engineer that tested that on a 5Ah pouch cell and
it was spectacular.? I found a shovel and tossed it out a window and watched burn
for 5 minutes.
?
>>>Experience:? Lithium from thumbnail sized pouch cells up to the DIY 48v 58kwh off grid bank
of?sixty-four 280 AH prisimatic LiFePO4 cells that's running the house as I type.
?
Then again I have 150AH flooded NiCd and with 7/8th inch terminal a short is amazing
I used that set of 10 (13.5v) to do some DC welding on 1/4" steel plate . That was
somewhere north of 125A.? ? High power does get respect.? ?Those cells have run
the station off grid for the last 14 years and still going strong.
?
I'm adding off grid? house lighting off 4x LFE for 5100 watthours.? They will be solar
charged.? Next iteration will bump that to 10KWH,? ?Those are 100ah 12V LFE so
care and lots of fuses are a good thing.? ? I cant divorce the power company as
all electric kitchen.? But I can seriously cut the bill.
?
--
Allison
------------------
Post online only,?
direct email will go to the bit bucket.


Re: QDX Low Receive but Xmit fine

 

I have looked at both the Terminal and Radio settings menus for Audio>Digi and Audio>SSB and can find no rx (sound card) out level adjustment. This is running fw 1.02.000. And, nothing is discussed about such an adjustment in the three versions of QMX operation manuals I have checked. If you can find such an adjustment, please post what and where it is in either settings screens.


Re: QMX I/Q question #qmx

 

On Sun, May 25, 2025 at 01:45 PM, <randal007@...> wrote:
Would I be able to use IQ for a panadapter and still be able to use my mic for SSB?
?
?
Yes, you can do this for SSB just like for CW.
?
You cannot do it for digital modes, because the single USB audio device is used for demodulated audio to/from the computer.? You can't send both IQ and demodulated audio.


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

 

I'm not sure if I've already stated this, but please count me in for the group buy for V2.0 of the QMX+ ABS mod.

Tks es 73,
Larry K3PEG


On Sun, May 25, 2025 at 2:16?PM Mitch NK3H via <mitch=[email protected]> wrote:
Likewise for a US group buy. Thanks. Mitch NK3H


Re: SSB Calibration question

 

Thanks, that makes sense.


Re: SSB Calibration question

 

It is fine the way it is.
Hans recently explained that during calibration the QMX operates as a transmitter and receiver.? The calibration problem is that the receiver sensitivity is too high.? Hans's software works to reduce the receiver gain as best it can.? For example it selects a band pass filter from another band to reduce gain.? If these tricks are not sufficient then the calibration will stop for that band.? Fortunately the transmitter is still very good with a partial calibration or uncalibrated.
Be happy!


Re: QMX I/Q question #qmx

 

I thought that I/Q was done over the virtual audio device, not the COM ports. (It's sent like stereo audio, with I on one channel and Q on the other.) To do both decoded audio and I/Q at the same time you'd need a second virtual audio device.

If you want to do digital modes alongside a panadapter, it should be possible to use a virtual tee audio device on the computer and do both the panadapter and the digital processing there. Send the virtual I/Q "audio" to the tee, and from there to both an SDR program (for the panadapter) and a digital program (Fldigi, WSJT-X, etc). You'll want at least a mid-range laptop to run both?programs well at the same time.

On Sun, May 25, 2025 at 4:45?PM randal007 via <randal007=[email protected]> wrote:
With the official SSB firmware now supporting 3 virtual com ports, are we able to use the soundcard and I/Q at the same time? So can I do digital modes and have a panadapter?
?
Would I be able to use IQ for a panadapter and still be able to use my mic for SSB?
?
Thanks
?
Randal
VE7NHW


QMX I/Q question #qmx

 

With the official SSB firmware now supporting 3 virtual com ports, are we able to use the soundcard and I/Q at the same time? So can I do digital modes and have a panadapter?
?
Would I be able to use IQ for a panadapter and still be able to use my mic for SSB?
?
Thanks
?
Randal
VE7NHW


Re: At Dayton Hamvention we are seeing a revolution in amateur radio before our eyes

 

I'm imagining a next product for QRP Labs, even though it wouldn't be a QRP radio. Maximum power output somewhere between 50W and 100W (with the ability to dial it down to 5W for QRP), a few more front panel controls, a larger display with a real waterfall, and perhaps a built-in antenna tuner. Otherwise it would have similar capabilities to the QMX: full band coverage from 160-6, all modes, EER/polar modulation for efficiency. Call it QBX, with the B standing for Base station; it wouldn't be primarily targeted at field operation,?though many operators might find?it suitable for POTA and Field Day.?


On Sun, May 25, 2025 at 12:50?PM Donald S Brant Jr via <dsbrantjr=[email protected]> wrote:
Hans:? Between your 5-watt class radios and the Aurora 500-watter, it would seem an obvious step for QRP Labs to make a 50-100-watt class radio with a good internal tuner in a KX3(ish) form factor, ideally with fine-grained?low-power settability down to, say, 1-5 watts for the QRP crowd.?
?
I know you like building extra functionality in your products, bonus style points for <<1 watt (<0dBm, even?) power operation would make it into a nice piece of lab gear.? The RF power stage hardware is so simple that implementing a second, low-power-range output might be practical, all of the filtering, etc. is common, just add switches.? One could also use an independent, lower power output as a tracking generator or at a different frequency for receiver testing, to drive a mixer LO, etc.? One could even switch in a noise source, for external use or (attenuated) for built-in test purposes.?
Once you are at low power a built-in step attenuator would be practical.? The microwave power sensor guys do this, I think they are using up to 3 separate switched detectors/attenuators to get the best dynamic range.?
A lower-power capability would also be safer, as a wrong button push could not cause a 100-watt OOPS, like turning down a big transmitter could.? Been there.
Add a gating input and/or an internal pulse generator/arbitrary waveform generator and it would make a nice pulsed RF source/beacon transmitter with good linear power control for propagation estimation; maybe the key input is/could be made fast enough.??
The possibilities for feature creep are endless.
?
Please keep these great products coming.? I hope you had an enjoyable visit to the States.
73, Don N2VGU
?
?


Re: New QMX - observations and best QSO

 

On the QMX, T507 in the tandem match SWR sensor has 10 turns between the antenna port and ground.
This calculator for the BN43-1502 shows 10 turns to have an inductance of 105uH,
which is in the same ballpark as Don's 22uH recommendation.
?
That's probably meant to be 10 turns through both holes.
My guess is that 10 turns through only one side will be about the same, but could be somewhat less.
?
A gas-tube arrestor is not a bad idea, add one if you wish.
Especially if using other rigs with the antenna.
But T507 should mostly solve antenna static discharge issues for the QMX/QMX+.
?
Jerry, KE7ER
?
On Sun, May 25, 2025 at 12:21 PM, Donald S Brant Jr wrote:

or a 22uH RF choke across the antenna will also drain any charge.


Re: New QMX - observations and best QSO

 

On Thu, May 22, 2025 at 11:29 AM, <jakob@...> wrote:
So be aware of this effect, especially on windy days with dry air.
The Allied militaries had to re-learn about this at he start of Desert Storm; receivers were having their front ends blown out by blowing sand-induced static charges on ungrounded long wire antennas.? My Korea/Vietnam era R-390A has a neon bulb directly across the input terminals, limiting the voltage to about 60V.??
I have a lot of gas tube arrestors in my station,? but a 1 to 5megOhm resistor, or a 22uH RF choke across the antenna will also drain any charge.? My terminated folded dipole antenna is DC continuous/grounded by design.
?
It is good practice to discharge any cable before attaching it to any piece of equipment by momentarily shorting the connector center pin and shield.??
Remember, Ground Is Good.


Re: 3 cell lipo battery, how to use it anyway

 

Allison,
?
You made a lot of good points.
Here's a few more.
?
Some may not know what you mean by "I charge them at .4C".
This tells us the rate you charge your battery in Amps, where 1C theoretically is the rate
at which a discharged battery will fully charge in one hour.
Theoretical in that charging efficiency is never quite 100%, and falls considerably at high charge rates.
So if you have a 2500 milliamp-hour 18650 cell, then a 1C charge rate is 2500 ma, and 0.4C is 2500*0.4=1000 ma.
An electric vehicle that claims to fully charge in 15 minutes has a battery system that can deal with a 4C charge rate.
?
Not sure about LiPo's but for LiFePO4 chemistry you should not float them at 3.65v forever.
In fact, leaving them floating at 3.5v will fully charge them and eventually damage them.
Something down around 3.4v should be safe.
?
Most lithium chemistries have a very low self discharge rate, I've got some in storage that don't discharge much in a year.
But a battery system usually includes a BMS (battery management system) that sucks at least some power,
this can discharge the battery in a matter of weeks.? Will Prowse has said that the most common failure
he sees of large LiFePO4 battery packs is that they get left in storage too long before getting used.?
And as you say, discharging too far will ruin them.??
?
Not a good idea to invest in lithium batteries and then procrastinate on using them.
It's been reported that for most electric vehicles, battery degradation is more due to calendar years of age
than the number of discharge cycles.? The exception would be extremely hard use, such as a taxi.
?
You say:? "Also Lithium tech DOES NOT have memory commonly associated with NiCd sealed batteries."
Opinions vary even on NiCd.? My impression is that the only well documented case of NiCd memory?
was with satellites in orbit, getting charged and discharged at constant rates on a very strict schedule
determined by when they were in the Earth's shadow.? Most earthly NiCd's fail simply because they
get left on the charger too long and dry out, it's difficult for a cheap charger to know when a NiCd
battery has been fully charged, some don't even try.? This and damage due to deep discharge
often gets blamed on "memory".? Which may be why you use the word "associated".
?
You said:? "Li tech can generally dump very large currents into a short or worse overheat
and go into runaway ( creates a conflagration) resulting in fire."
LiPo chemistry can run away on you, LiFePO4 pretty much never does and is much safer.
Both can dump out some incredibly large currents when shorted, but then so can lead acid.
Have never had an accident with Lithium and have used a lot of it.
Did have a lead acid battery blow up in my face once though, was just off the charger
and a spark made when connecting it up ignited the H+O boiling out the vent caps.
I consider lead acid considerably more dangerous than Lithium, though admittedly
a LiPo lithium fire would be awful hard to put out.
?
Experience:? Lithium from thumbnail sized pouch cells up to the DIY 48v 58kwh off grid bank
of sixty-four 280 AH prisimatic LiFePO4 cells that's running the house as I type.
?
Jerry, KE7ER