Re: AA Batteries and QMX+: is it safe to use?
On Wed, Jul 10, 2024 at 03:34 PM, Andrew wrote:
However, the output voltage is 12.9 volts.
Check the voltage actually getting to the PC board (not at the battery) when the radio is receiving and when transmitting into a dummy load. I suspect you will find that it drops to a safe level when transmitting, which is when it most important for the finals' safety. This is due to wire and contact resistance and internal resistance of alkaline batteries.? Rechargeables tend to not drop their voltage as much so check before transmitting into an imperfect load. Too high for comfort?? Put in a dummy cell or a couple of diodes (maybe switchable) and lower the voltage that way. A little higher than 12?? Probably OK but the risk rises with VSWR and voltage, so you are in test pilot territory. Don't say Hans didn't tell you so! 73, Don N2VGU
|
Re: AA Batteries and QMX+: is it safe to use?
Using NiMH cells will reduce the output voltage.? Tho fully charged NiMH cells do have a higher than1.2VDC / cell.
Replace one (or two) of the AA cells with a 'dummy' cell - both will offer a lower voltage.?
I happen to use a 10xAA cell battery pack for my portable rigs.? Use a voltmeter to determine what is the actual battery voltage before use.
Good luck.
|
Hi All,
I have just finished the build on the QMX+ Very pleased with it and have made several contacts on FT8. However the O/P power is low on higher bands:
160m 5.0W
80m? 4.1W
40m? 3.2W
30m? 3.4W
20m? 3.2W
17m? 3.6W
15m? 3.4W
12m? 2.5W
10m? 1.8W
6m??? 0.9W
I would be happy with 3-5W but 0.9W on 6m is a bit low as my main interest is the higher bands which was the main reason for buying the QMX+. I already have a QDX which performs nicely..
Does anybody have any suggestions why the output may be so low on 10m & 6m?
BTW the power output was measured with a Marconi Power meter and correlates well with the QMX+ figures...
Thanks in advance for any sugestions
73 de Dave G4FAW
|
I should experiment rather than ask, but can the QCX be adjusted for a narrower passband?
--
Brent DeWitt, AB1LF
Milford, MA
|
AA Batteries and QMX+: is it safe to use?
Based on some of the threads I ordered a 8 AA battery case as a backup power source and for RFI reference against other rechargeable battery solutions.? However, the output voltage is 12.9 volts.? These at Alkaline 1.5 volt AA Amazon brand batteries.? So the question is: how safe is using AA batteries on a QMX+??
I am currently using a voltage reducer (buck convertor) to keep the voltage on my Bioenna battery around 11.5v.??? Not sure where I should be measuring voltage to determine a safe maximum output from any battery.
|
Re: A question for builders
Wow, I am 82 and have been soldering since 1955. I have been building kits all those years. Just finished QMX+. I will keep smelling that solder smoke.
Mike WA8UOC
Gary,
I am 79 1/2 and have found over the years that a deep breath over a smoking soldering tool energizes me and clarifies my thought processes.? I agree with your thoughts.? Be the REASON someone smiles today.
Dave K8WPE On Jul 9, 2024, at 12:11?PM, Gary O'Neil <n3go@...> wrote:
?I think I have to take issue with your comment about the creator Wayne!
I believe the creator fully intended solder fumes to motivate and inspire… hams in particular… in any environment. I have many years of practice, experience, and exposure to support this assertion. I find that the smell of solder always seems to “resin”ate with me. :-)
I have soldered indoors and out, in hot weather and cold, in rain, sleet, and hail… err perhaps that one’s a stretch. :-) In any case however; no matter what I try… whether standing to the left, to the right, keeping the work at arm’s length at any angle (in azimuth or elevation) at, above, or below eye level, opening a window, holding my breath, even exhaling over it as I’m soldering. Like a vortex from a cannon, the fumes rise, take form, and make a beeline to my nostrils the moment the solder meets the iron.?
Since this absolutely “NEVER” fails to behave any other way, I can only conclude that it has to be divine intervention. What else could be guiding it so accurately and precisely? :-)
Solder smoke is perhaps the one olfactory stimulus that can divert a hungry being from the odiferous sensations emanating from country kitchens on Thanksgiving Day.** ?It remains the one familiar carry over that lingers from our humble glass blown beginnings.
--
72
Gary, N3GO
** ?Hams are not Turkeys!
dit dit
|
Re: Issues with summer travel and hot cars?
Nolan -
This was something I'd been curious about. The specs for the components in the QCX mini seemed to be phone specs, which are pretty rugged. To test this I've done an ad hoc test - I've left a 40 meter QCX mini sit in the trunk of our car (a dark blue sedan) since mid February. We're located in Philadelphia PA so the weather isn't totally extreme but air temperature has ranged from about 20F to 95F during that period (and it will get hotter in the sun). So far the unit still works (just pulled it out and tested it).
John KI3J
|
Re: QLG2 GPS Interface With QCX, QMX
Hi Bill.
Hope this helps........
If your GPS kit is the one that was ordered with the QMX then the full installation instructions are in the 'firmware' manual on the QRP-LABS website in the GL2 section. It's full name is: Manual_1_00a.pdf.?
That one comes with a standard USB connector you can solder on in two different places. That's where I get the +5v power. You also would need to install the jumper associated with doing that. Also detailed in the instructions.
I chose to mount it on the lower end of the board location to leave the side signal output pins fully accessible.? That info is in the 3rd paragraph of Section 3.2 of the assembly instructions.
If it's an older GL kit, there was no USB connector. You would have to purchase one if you want to go that way for power.
Otherwise you have to provide the +5v through one of the other pins available.
DO NOTE THE CAUTION about NOT providing +5v from TWO different sources at the same time, ever. And ... That the +5v needs to be just that, and 'clean'.?
Also, you can't leave the GPS plugged in all the time. Just long enough right after startup for the QMX to pick up the GPS data and set the internal time for routine operation.? I think you might be able to leave it in if using Beacon Mode, but I haven't read fully that or tried it since I don't 'Beacon' as such.
I've attached a picture of mine here.
73 GREG KI4NVX
Show trimmed content
On Wed, Jul 10, 2024 at 12:54 PM, Bill Jobes via groups.io <jobes@...> wrote: Is there a single source with either a video or text on precisely how to connect and use the GPS Receiver Kit ?? I'm new to WSPR and am having trouble cobbling together info on connections, cables and operations.
Thanks !
- Bill? W3WJ
|
Re: QLG2 GPS Interface With QCX, QMX
On 10/07/2024 16:54, Bill Jobes via groups.io wrote: Is there a single source with either a video or text on precisely how to connect and use the GPS Receiver Kit ? The GPS interface (1pps and 9600 baud serial data) shares the same pins as the paddle dit and dah signals (necessary due to limited processor I/O). The style of this interface is the same as the earlier QCX-series CW transceiver kits.
|
Re: Reduce RF power on QMX
Hi Rick,
to get the QMX RF output power from 5W to about 2W for now it is the only option to lower the power supply voltage from 12V to 8V to. If this is a 12V QMX.
For 200mW you will need a 10dB power attenuator.
--
73 Bojan S53DZ
|
Re: Reduce RF power on QMX
There are settings in setup for each band. Use putty to telnet to it, obviously not when using any other app for digital modes.?
I also have a voltage control on my power supply and I use that in emergency?
Paul Wamble 214-405-5876, iPhone?
toggle quoted message
Show quoted text
On Jul 10, 2024, at 1:33?PM, Rick Trommer via groups.io <rhtrommer@...> wrote:
?What is the best way to reduce the RF from 5 watts to around 2 watts on the QMX transceiver? I see nothing listed using the Cat Command... I would like to be able to run about 200Mw on WSPR and around 2 watts on CW....
Thanks in advance..
--
Rick
W5NR
|
What is the best way to reduce the RF from 5 watts to around 2 watts on the QMX transceiver? I see nothing listed using the Cat Command... I would like to be able to run about 200Mw on WSPR and around 2 watts on CW....
Thanks in advance..
--
Rick
W5NR
|
Re: My QMX+ has a .3 ohm short on VDD
Dear David,
I am glad you are seeing some progress. As best the reports say, shorting the VDD to ground will not necessarily kill the 3.3v switching supply. So hopefully, you don't need a new PCB #2.
So... you were able to load the firmware which means the linear regulator of PCB #2 must be ok, which is connected also to VDD. Otherwise, the processor would not be able to boot. Now that you loaded the firmware, the processor is now trying turn on the switching part of VDD (or at least this is my understanding). But I wonder about your measurement check of VDD. You report 2.5v on VDD and a resistance (without power, of course) of 0.4 ohm. That would be I = V/R or 6.25 Amps. So I wonder about that resistance check and I'm not seeing on the schematic how that would make sense. You can unplug the switching board PCB #2 and measure the resistance again.
Are you possibly using a current limited supply which is not able to provide the current necessary for full boot up? Remember the linear regulator is also connected (but get's disabled at some point in the boot process) so the VDD onto the main board should definitely not measure so low as 0.4 ohm, Otherwise I don't think you would have been able to load the firmware.
73,
Gregg W7GRM
|
Re: Another QMX+ got onto the air + Low Tx Output
Yep, same here - drops off quite a bit as frequency goes up, unfortunately. I've been meaning to play around with toroid wire spacing to see if I can get an improvement but in the mean time I've gone back to my mid-band QMX where I've got nearly solid 4-5 watts on all six bands. :-)
--
Jim / K7TXA
Eagle, ID
SKCC 10447T
BUG 301
|
Re: Another QMX+ got onto the air + Low Tx Output
Just got My QMX+ finished, and I am seeing similar performance on Tx. Mine starts off at over 5W on Top Band but goes down to just over 1W on 6m. I was goung to ask the question on here but spotted your post. Has anybody else seen this, am I unique or is this common? What power do others? see in the various bands?
Have made several contacts already but am a bit dissappointed with Tx performance..
Thanks all
73 de G4FAW
|
QLG2 GPS Interface With QCX, QMX
Is there a single source with either a video or text on precisely how to connect and use the GPS Receiver Kit ?? I'm new to WSPR and am having trouble cobbling together info on connections, cables and operations.
Thanks !
- Bill? W3WJ
|
On Wed, Jul 10, 2024 at 05:47 PM, mux_folder2001 wrote:
I started by switching the QMX+ to IQ mode
Afaik no IQ mode. The real audio should be sent to the computer (see chapter 6 of operating manual). 73, Ludwig
|
Never mind ?. Had to be something stupid and it was. Putting the rig in IQ mode is not right. I look it out of IQ mode and all is well.
Tony
AD0VC
toggle quoted message
Show quoted text
From: QRPLabs@groups.io <QRPLabs@groups.io> on behalf of mux_folder2001 <canthony15@...>
Sent: Wednesday, July 10, 2024 10:02 AM
To: QRPLabs@groups.io <QRPLabs@groups.io>
Subject: Re: [QRPLabs] QMX+ FT8 problems
?
Forgot to mention that I also set up the audio to use the QMX audio device.
Tony
AD0VC
From: QRPLabs@groups.io <QRPLabs@groups.io> on behalf of mux_folder2001 <canthony15@...>
Sent: Wednesday, July 10, 2024 9:47 AM
To: QRPLabs@groups.io <QRPLabs@groups.io>
Subject: [QRPLabs] QMX+ FT8 problems
?
Since I got my QMX+ back from Jeff (W1NC), I have been using it on CW and it works? fine. Today I decided to try FT8. I have a QDX so I am familiar with QRPLabs FT8 setup and operation. I started by switching the QMX+ to IQ mode and setting the rig to
Digimode. I started JTDX and configured the com port and set it for CAT mode. I tested CAT and got the green response from JTDX.? JTDX is configured for FT8 (still set up from my QDX) but something is not right.
The waterfall shows no proper FT8 signals. I see occasional tracks that look like CW. It looked like it was mistuned but the QMX frequency display is correct. It is the same sort of behavior on all bands. I put it on 20 meters where I know there are lots of
FT8 signals (I can see them on my SDR). Then I set up my signal generator with a few feet of wire as an antenna and set it to 14072.5 (1.5Khz BELOW 14074) and sure enough, the carrier appeared in the waterfall at the 1500Hz point. It seems that the QMX+ is
on the wrong sideband. I tried increasing the generator frequency a little and the waterfall blip slid to the left, closer to 14074.
Then I tried transmit. I get no response from the QMX+. There are no dots indicating transmit mode. The power slider is all the way up and Windows (W11) is set with sliders at max.?
If these two symptoms are related, maybe it is CAT? I tried setting to TS480 with no change in the symptoms. I also tried a factory reset.
Any suggestions would be welcome.
Thanks,
Tony
AD0VC
|
QMX requires TS-440, I assume same for QMX+…? Paul Wamble 214-405-5876, iPhone?
toggle quoted message
Show quoted text
On Jul 10, 2024, at 11:03?AM, mux_folder2001 via groups.io <canthony15@...> wrote:
?
Forgot to mention that I also set up the audio to use the QMX audio device.
Tony
AD0VC
From: QRPLabs@groups.io <QRPLabs@groups.io> on behalf of mux_folder2001 <canthony15@...>
Sent: Wednesday, July 10, 2024 9:47 AM
To: QRPLabs@groups.io <QRPLabs@groups.io>
Subject: [QRPLabs] QMX+ FT8 problems
?
Since I got my QMX+ back from Jeff (W1NC), I have been using it on CW and it works? fine. Today I decided to try FT8. I have a QDX so I am familiar with QRPLabs FT8 setup and operation. I started by switching the QMX+ to IQ mode and setting the rig to
Digimode. I started JTDX and configured the com port and set it for CAT mode. I tested CAT and got the green response from JTDX.? JTDX is configured for FT8 (still set up from my QDX) but something is not right.
The waterfall shows no proper FT8 signals. I see occasional tracks that look like CW. It looked like it was mistuned but the QMX frequency display is correct. It is the same sort of behavior on all bands. I put it on 20 meters where I know there are lots of
FT8 signals (I can see them on my SDR). Then I set up my signal generator with a few feet of wire as an antenna and set it to 14072.5 (1.5Khz BELOW 14074) and sure enough, the carrier appeared in the waterfall at the 1500Hz point. It seems that the QMX+ is
on the wrong sideband. I tried increasing the generator frequency a little and the waterfall blip slid to the left, closer to 14074.
Then I tried transmit. I get no response from the QMX+. There are no dots indicating transmit mode. The power slider is all the way up and Windows (W11) is set with sliders at max.?
If these two symptoms are related, maybe it is CAT? I tried setting to TS480 with no change in the symptoms. I also tried a factory reset.
Any suggestions would be welcome.
Thanks,
Tony
AD0VC
|
Forgot to mention that I also set up the audio to use the QMX audio device.
Tony
AD0VC
toggle quoted message
Show quoted text
From: QRPLabs@groups.io <QRPLabs@groups.io> on behalf of mux_folder2001 <canthony15@...>
Sent: Wednesday, July 10, 2024 9:47 AM
To: QRPLabs@groups.io <QRPLabs@groups.io>
Subject: [QRPLabs] QMX+ FT8 problems
?
Since I got my QMX+ back from Jeff (W1NC), I have been using it on CW and it works? fine. Today I decided to try FT8. I have a QDX so I am familiar with QRPLabs FT8 setup and operation. I started by switching the QMX+ to IQ mode and setting the rig to
Digimode. I started JTDX and configured the com port and set it for CAT mode. I tested CAT and got the green response from JTDX.? JTDX is configured for FT8 (still set up from my QDX) but something is not right.
The waterfall shows no proper FT8 signals. I see occasional tracks that look like CW. It looked like it was mistuned but the QMX frequency display is correct. It is the same sort of behavior on all bands. I put it on 20 meters where I know there are lots of
FT8 signals (I can see them on my SDR). Then I set up my signal generator with a few feet of wire as an antenna and set it to 14072.5 (1.5Khz BELOW 14074) and sure enough, the carrier appeared in the waterfall at the 1500Hz point. It seems that the QMX+ is
on the wrong sideband. I tried increasing the generator frequency a little and the waterfall blip slid to the left, closer to 14074.
Then I tried transmit. I get no response from the QMX+. There are no dots indicating transmit mode. The power slider is all the way up and Windows (W11) is set with sliders at max.?
If these two symptoms are related, maybe it is CAT? I tried setting to TS480 with no change in the symptoms. I also tried a factory reset.
Any suggestions would be welcome.
Thanks,
Tony
AD0VC
|
Donald S Brant Jr
Brent DeWitt
Paul K5EBP
Rick Trommer