Re: is there anyone who would be willing to replace the si5153a synthesizer chip on my qcx?
Hi Ted. I am not nearby, but will replace it for you if you can send it to me. I have build many many radios, even the QMX that is complete and working. I love smd and associated things like this and have built many for others. I will do it for free with the exception of postage. Do you have the 5351a? replacement?
Give me a text or look up N1GMM on QRZ and email me.
Best! 73
Guy
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Re: QMX ---PCB Rev 2 --
#qmx
P.S. Chris
I got that the wrong way around I think:
WTST is for 9V QDX
RWTST is for 12V QDX
73 Hans G0UPL
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Re: QMX - smoke - another C107/Q108 failure
I would still like to see what the power sequencing with a scope of VDD and VCC looks like during power ON and Power OFF whether using the pushbutton or pulling the V_IN power lead. Just the details of the 1st second after switching, once and with a sequence of ON/OFF several times. Both Plug-In PCBs installed in a working QMC.?
73 Kees K5BCQ
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Re: QMX ---PCB Rev 2 --
#qmx
Hello Willie
> I am a retired physicist on the north side of my eightyth decade.
I am also a physicist (graduated 1993, Imperial College Physics BSc, London university); but have never officially been a practicing physicist (debatable)! Please do also refer to my 52-tips video? which gives construction advice.?
> In doing due diligence, one has to ask the tough questions.? > Does management see a Revision 2 PCB board on the? > way with all the known fixes on it??
I always do new PCB revisions, particularly in the early days of a product (say, the first year). There will always be a little tweak that I can make that will make construction marginally easier. Such as a slightly moved pad, or a slightly larger hole someplace.?
There are very very few issues with QMX (surprisingly few).?
1) A manufacturing defect: the SMPS has a potential short between Q103 and Q104 drains which appears to affect around 10-30% of boards. However we are now testing all SMPS boards before shipment and fixing any that have the short. Therefore this problem is ALREADY solved... nobody ordering now needs to worry about it. For the next batch I'll move Q104 a little further away just to remove the need for any corrective work pre-shipment.?
2) Missing 5.1K pulldown resistors on the USB CC pins, which are needed if you are using a device with a real USB-C port, and a direct USB-C-to-USB-C cable (not an adapter).?
3) 20m Low power was an assembly instruction error; 20m low receive sensitivity was also resolved and is just an amendment to the manual.?
So really, yes there will be a Rev 2 PCB, but it is minor stuff, and there will nothing wrong with having a Rev 1 PCB.?
> Would new firmware depend on having the new Revision? > 2 PCB board leaving the Revision 1 QMX units behind??
NO! Like all the QRP Labs kits, all firmware revisions in general work with all PCB?revisions. Even the latest QCX firmware can run on the oldest Rev 1 QCX-classic PCB from 2017. If there is some new hardware feature such as the on/off controllable backlight on QCX-mini, or the CAT control port in QCX, then yes that requires some specific hardware modification etc. or PCB revision.?
Hi Chris
> Also, I am looking forward to building a second unit for? > high bands but I expect this will be delayed until the? > problem with some QDX having low power on 10M? > (Possibly QDX T1 identical to QMX T501) is resolved.?? > Hans does the QDX low power also happen with the? > 9V T1 winding.
That was already resolved, Chris. The 12V QDX is less likely to suffer low power output, the 9V QDX is more likely to suffer low power output. The solution in both cases is a new output transformer design by Ross EX0AA. If you search this forum for "WTST" (Weird Twisted Sisters Transformer) then this is the solution for a high-band 12V QDX. If you search the forum for "RWTST" (Really Weird Twisted Sisters Transformer) then this is the solution for the high-band 9V QDX. The twisted output transformers completely solve the problem of sometimes getting low power output on 10m.?
FYI we are also using the same twisted transformers on all QMX we assemble here in QRP Labs HQ for people (12V WTST and 9V RWTST).?
I do need to urgently update the QDX documentation, and the QMX documentation (ahead of the high-band QMX where the twisted transformers shine).?
On Mon, Aug 28, 2023 at 4:35?PM Chris KB1NLW via <chrisrey1= [email protected]> wrote: Hans incorporated two major hardware features that require future firmware.? These are SWR measurement and the ability to modulate RF amplitude.? I believe that the first firmware that combines the features of QCX and QDX has required more debugging than expected.? There have also been a couple of significant hardware issues that were resolved.?
Thus, I am sure that Hans will include the expanded features, but (as with all software) it will take longer than he expected.
Also, I am looking forward to building a second unit for high bands but I expect this will be delayed until the problem with some QDX having low power on 10M (Possibly QDX T1 identical to QMX T501) is resolved.? Hans does the QDX low power also happen with the 9V T1 winding.
Finally Hans is very creative in his designs and I believe all in this group admire him.
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Re: QMX ---PCB Rev 2 --
#qmx
KB1NLW
Thanks for your input. You have stepped forward to provide powerful support for QRP-Labs. I might point out why I am being so forward with due diligence. I am a retired physicist on the north side of my eightyth decade. I was first licensed in 1957. My mind
is clear as ever, but the body is shot. This, if bought, will probably be my last rig, so I want it to be right from the first. In reality, I would prefer the high bands to start with, but that is not there. Also, I have had problems with the early SDR units
and a little skittish there. And lastly, I am somewhat worried about being able to build the monster even though that is a large part of my enjoyment. Not mentally but physically. All of the teething problems have helped spark that concern.
Part of the due diligence is to figure how far down the road some the upgrades are. From what you say, the high band version is the only one requiring new hardware.
Your personal support of Hans and QRP-Labs is more that welcome and means a lot to me. I will hang around a while longer hoping Hans himself will chip in.
toggle quoted message
Show quoted text
Hans incorporated two major hardware features that require future firmware.? These are SWR measurement and the ability to modulate RF amplitude.? I believe that the first firmware that combines the features of QCX and QDX has required more debugging than
expected.? There have also been a couple of significant hardware issues that were resolved.?
Thus, I am sure that Hans will include the expanded features, but (as with all software) it will take longer than he expected.
Also, I am looking forward to building a second unit for high bands but I expect this will be delayed until the problem with some QDX having low power on 10M (Possibly QDX T1 identical to QMX T501) is resolved.? Hans does the QDX low power also happen with
the 9V T1 winding.
Finally Hans is very creative in his designs and I believe all in this group admire him.
-- N5SE
Billy Wayne Moore
7066 Shady Knoll Ln
Willis, TX 77318-6324
Phone: 936-537-2975???
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Re: QDX V1: RF-sensing switch for the 50W Class C amplifier
The problem with any RF-sensing TX switching scheme is that the RF needs to be present before switching is initiated, which ensures that you are hot-switching the driver and amplifier.?
In CW this would result in a truncated first character and possibly key clicks from the abrupt rise time.
73, Don N2VGU
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Re: What is BitBanger (and SCAMP)?
I just got a notification of being ’sold’(?) as a Not-The-KickStarter at for $150 that sounds remarkably similar to the QMX plus JS8Call.
I'm not seeing much similarity to QMX ;-)? ??
SCAMP could easily be implemented on QMX but there is quite a long?list of much more?urgent things which have to be done first.?
It will, as Andrew KI7FXL said, be interesting to see what the adoption of this is. There are quite a lot of new modes? which come and go.?
To add to John F5VLF's list of computer implementations - more recently there's another SCAMP, which is a homebrew 16-bit discrete logic CPU (such CPU's are another interest of mine) see?
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Re: What is BitBanger (and SCAMP)?
Looks interesting to me. I think that having a built-in keyboard mode is really great. That is certainly a feature that I think should make it into the much-more-powerful (cpu-wise) QDX/QMX. Will be interesting to see what this SCAMP mode is and how/if it's embraced by the community.
--
73
Andrew KI7FXL
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Re: What is BitBanger (and SCAMP)?
The term SCAMP has already been used in small computer systems. If my researches are correct, one was a FORTH-based micro from the early 1970s. Another was a little later. It was APL-based and supposedly was an ancestor of the 5100.
John F5VLF
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On 28 Aug 2023, at 15:38, William Smith <w_smith@...> wrote:
I just got a notification of being ’sold’(?) as a Not-The-KickStarter at for $150 that sounds remarkably similar to the QMX plus JS8Call.
Anyone know any more about this? Not really interested myself, have plenty of QDXen at a much lower price point and _way_ better support, (They have a dedicated Slack channel?) and:
/*
Delivery is no earlier than late August 2023. Will be posted here and on the ORI website at
*/
SCAMP will be described on Sept 9, so it’s too early to ask if it’ll run on the QDX/QMX, but there’s:
<blob:> which I skimmed over, didn’t really (bother to try to) understand.
Anyway, please note the ‘mute this topic’ button below if you have no interest.
73, Willie N1JBJ
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What is BitBanger (and SCAMP)?
I just got a notification of being ’sold’(?) as a Not-The-KickStarter at for $150 that sounds remarkably similar to the QMX plus JS8Call.
Anyone know any more about this? Not really interested myself, have plenty of QDXen at a much lower price point and _way_ better support, (They have a dedicated Slack channel?) and:
/*
Delivery is no earlier than late August 2023. Will be posted here and on the ORI website at
*/
SCAMP will be described on Sept 9, so it’s too early to ask if it’ll run on the QDX/QMX, but there’s:
<blob:> which I skimmed over, didn’t really (bother to try to) understand.
Anyway, please note the ‘mute this topic’ button below if you have no interest.
73, Willie N1JBJ
|
Re: QMX ---PCB Rev 2 --
#qmx
Hans incorporated two major hardware features that require future firmware.? These are SWR measurement and the ability to modulate RF amplitude.? I believe that the first firmware that combines the features of QCX and QDX has required more debugging than expected.? There have also been a couple of significant hardware issues that were resolved.?
Thus, I am sure that Hans will include the expanded features, but (as with all software) it will take longer than he expected.
Also, I am looking forward to building a second unit for high bands but I expect this will be delayed until the problem with some QDX having low power on 10M (Possibly QDX T1 identical to QMX T501) is resolved.? Hans does the QDX low power also happen with the 9V T1 winding.
Finally Hans is very creative in his designs and I believe all in this group admire him.
|
Re: QDX dead on receive but Ok on transmit diag led 2 on.
On 28/08/2023 10:56, Dave ZL1TIU wrote: Tried a factory reset, Dave, Yes, this has been reported on various QRP Labs rigs. Not a common thing but sometimes cures strange problems. The diagnostic LED is now off and the QDX is receiving. Note that light has no meaning for the user and has been removed on later versions. Also note the audio input analysis is for looking at the transmit input. Read the manual, not a simple setup and for interest rather than diagnostics. 73 Alan G4ZFQ
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This is the stand I 3D printed from Thingiverse, there are several options available.?
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QDX V1: RF-sensing switch for the 50W Class C amplifier
I have an original version QDX, which puts ~3 W into my 20 M dipole about 25 feet above ground. ?It works well and has produced many FT8 contacts, though many of my calls go unanswered on the crowded band. ?I figured another 10 dB of power would be a big help. ?I have a 50W class C amplifier, which I use with my QCX+, but the original QDX does not provide a 5 VDC output to activate the amplifier. ?So I built a switch that taps a bit of power from the QDX to the amp and provides the 5 VDC to place the amplifier in transmit mode. ?The switch is inserted in the coaxial cable between the QDX and the amplifier via a BNC tee, as shown in the photo. ?I used a 9V alkaline battery for the DC power source, for convenience (beneath the circuit board in the photo). ?No current is drawn from the battery during receive, and only ~7 mA during transmit (mostly to power the red LED in the amplifier. ? But this is not a good long-term solution. ?The turn-on time for the transmit signal is of the order of a mSec or so, but the “hang time” or turn-off time is about 250 mSec. ?This is acceptable for FT8, but would need to be shorter for cw operation. ?Reducing the values of C1 and C2 to say 10 nF should reduce the turn-off time, but I didn't experiment with component values in the circuit. ?With the amplifier the rf output power is now 35 W, the 10 dB improvement I sought. ?This has improved the overall contact success rate, as anticipated. 73, ?Ben ?K0IKR
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Re: QMX ---PCB Rev 2 --
#qmx
Thanks a lot William, you have given a powerful lucid informative answer for QRP-labs support of their products. I will take these under consideration as I make my decision. You have been most helpful.
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Show quoted text
If history (and following along in this group) is any guide, of course there will be PCB revisions as required and as Hans has to order new batches.? Sounds like he already has minor tweaks to the SMPS boards in the queue.
Also, if history is any guide, all firmware will run on all revisions.? Rev 1 QDX and Rev 5 QDX can all run the latest QDX formware, for instance:
/*
Assembly manual for PCB Rev 5 (document version 1.18f published 04-Apr-2023)
Operating manual for firmware 1_10 (document version 1_10 published 19-Jul-2023)
*/
73, Willie N1JBJ
> On Aug 28, 2023, at 7:56 AM, N5SE <bwmoore@...> wrote:
>
> In doing due diligence, one has to ask the tough questions. Does management see a Revision 2 PCB board on the way with all the known fixes on it? Would new firmware depend on having the new Revision 2 PCB board leaving the Revision 1 QMX units behind? Yes,
this is a tough question, but a valid concern in making a decision. Thanks in advance, Billy
> --
> N5SE
> Billy Wayne Moore
> 7066 Shady Knoll Ln
> Willis, TX 77318-6324
> Phone: 936-537-2975
-- N5SE
Billy Wayne Moore
7066 Shady Knoll Ln
Willis, TX 77318-6324
Phone: 936-537-2975???
|
Re: QMX ---PCB Rev 2 --
#qmx
If history (and following along in this group) is any guide, of course there will be PCB revisions as required and as Hans has to order new batches. Sounds like he already has minor tweaks to the SMPS boards in the queue.
Also, if history is any guide, all firmware will run on all revisions. Rev 1 QDX and Rev 5 QDX can all run the latest QDX formware, for instance:
/*
Assembly manual for PCB Rev 5 (document version 1.18f published 04-Apr-2023)
Operating manual for firmware 1_10 (document version 1_10 published 19-Jul-2023)
*/
73, Willie N1JBJ
toggle quoted message
Show quoted text
On Aug 28, 2023, at 7:56 AM, N5SE <bwmoore@...> wrote:
In doing due diligence, one has to ask the tough questions. Does management see a Revision 2 PCB board on the way with all the known fixes on it? Would new firmware depend on having the new Revision 2 PCB board leaving the Revision 1 QMX units behind? Yes, this is a tough question, but a valid concern in making a decision. Thanks in advance, Billy
--
N5SE
Billy Wayne Moore
7066 Shady Knoll Ln
Willis, TX 77318-6324
Phone: 936-537-2975
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Re: QMX ---PCB Rev 2 --
#qmx
Thanks for the response. However, I have no idea of the meaning. Please elaborate so we can have an erudite discussion.
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Show quoted text
I'll make the popcorn...?
-- N5SE
Billy Wayne Moore
7066 Shady Knoll Ln
Willis, TX 77318-6324
Phone: 936-537-2975???
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Re: QMX ---PCB Rev 2 --
#qmx
I'll make the popcorn...?
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I have a weird problem. No waterfall. The rig goes through normal fire up. Don't know if there is output or not. I use my tablet, ft8cn and an end fed log wire and am on 7.074 mHz.
HIF
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Hi Group,
I don't know if this has come up here before (a search turned nothing up) but thought I would share the stands I originally used on my (tr)uSDX radio's.? They work equally well for the QMX and QCX Mini's.?
73,
Robert, WA2T
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Guy Mengel N1GMM
N5SE
Donald S Brant Jr
Andrew KI7FXL
Leland Lannoye, W9HIF