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Re: QMX+ failed with power issues on first power up
So if the decision on when to jump from linear to switching is made based on the 5 volt output, and if the 5 volt output is actually 5 volts, but if the 3.3 volt output is actually 3 volts (10% low), then the ADC in the microprocessor is probably using the 3.3v as a reference and saying the 5volt output is 5% high (the screen shows 5.54) and therefore not going over to switching mode.
That also explains the 8.1 volts on the screen when I put 7.5 volts in. That makes me a lot happier that the microprocessor is still OK. |
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Re: QMX+ - Another One Comes To Life!
This one is resolved - mostly. It turns out that when the CR2032 battery is inserted into its holder, the connectors on the right side (the minus side) short out against the positive part of the battery. I've looked at this rather closely under my magnifiers and for the life of me I cannot see how this holder ever can work as designed. So, either I've got a defective battery holder or there is a design flaw in this thing. I was able to circumvent the problem by placing a small (very small) piece of tape on the edge of the battery. Thus, when it is inserted into the holder, the two little prongs still contact the minus side of the battery, but the base of those pins no longer come in contact with the slightly larger positive part of the battery.
Has anyone else come across this situation? Wondering if Hans has followed this thread...? -- Jim / K7TXA Eagle, ID SKCC 10447T BUG 301 |
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Re: QMX+ failed with power issues on first power up
The system does come up in linear mode initially.? LIN_REG_EN is an output of the MCU. It disconnects the linear regulator when the MCU decides the SMPS supply voltages are ready. IIRC the MCU monitors ADC_5V to make that decision. The ADC_3V3 signal is what is displayed as the 3.3V SMPS output. JZ On Sat, Jun 22, 2024 at 1:27?PM w8gu via <w8gu=[email protected]> wrote: I do not really understand the enabling of the linear versus switching 3.3. |
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Re: QMX+ failed with power issues on first power up
I do not really understand the enabling of the linear versus switching 3.3.
Does the system come up in linear initially and get moved to switching by the microprocessor? Is LIN_REG_EN an output of the microprocessor? If so, what does the microprocessor use to determine that it is time to go to switching mode? Is the 3.3 voltage on the hardware diagnostics the voltage of the output of the switching mode 3.3 (i.e., ADC_5V)? ================= still on my to-do list is - checking the resistance/voltage on L201 - Looking at the outputs CLK0/1/2 on a scope. Not likely to get to these until tomorrow.? Planning on visiting our club's field day operations. |
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Re: QMX+ failed with power issues on first power up
OK. A failure of Q113 would have a similar set of consequences. The current to heat D105 has to be coming from somewhere...JZ On Sat, Jun 22, 2024 at 1:17?PM w8gu via <w8gu=[email protected]> wrote: No gate-to-source short on Q109 |
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Re: QMX+ failed with power issues on first power up
Mark, Check Q109 for a gate-to-source short. If such should exist, Q109 will never turn on. D105 will overheat, and the SMPS module may stay in linear mode, causing the linear regulator to overheat. JZ On Sat, Jun 22, 2024 at 12:42?PM John Z via <jdzbrozek=[email protected]> wrote:
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Re: QMX+ failed with power issues on first power up
CLK0 and CLK1 will both be at approximately the receive frequency...
Except that I don't know what my receive frequency is.?? The only screen that I have seen is the "hardware diagnostics".? It came up when I opened the interface in putty and hit enter. I just get [black on line 1/blank on line 2] on the screen, so I don't have a frequency. I have assumed that it shows me hardware diagnostics -only- because things are not right yet. |
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Re: QMX+ failed with power issues on first power up
Yes, some fine wires will be needed to probe L201. The CLK signals should be 3.3V square waves with 50% duty cycle. In receive, CLK0 and CLK1 will both be at approximately the receive frequency but phase separated by 90 degrees. As something is loading the 3.3V supply, you will probably see a lower voltage.? 3.3V In transmit, CLK2 will be at the transmit frequency, also a square wave with a 50% duty cycle. Same comment. Use a dummy load,? don't blow up the TX. I'm still thinking about what the hot components on the SMPS might be telling us. JZ On Sat, Jun 22, 2024 at 12:32?PM w8gu via <w8gu=[email protected]> wrote: On the measurement of L201, it appears to be under the 3.3 volt power supply.?? |
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Re: QMX+ failed with power issues on first power up
On the measurement of L201, it appears to be under the 3.3 volt power supply.??
I assume that you mean for me to solder some tiny wires to L201 and replace the power supply, then make the voltage measurement.? Is that correct? Also, where would I find a reference for what CLK0, CLK1, and CLK2 should be? |
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Re: QMX+ and 50W QCX Amp
? Same amp basic design? as the cheaper kit in the fully built up version.? Be a hero;? ?solder your own up. THere's a lot of meat in his video - basic schematic included and so on.? He's done a few more on this amp and issues with the PTT which he fixed by adding one more PNP to make it more sensitive.? Ie some? SS? rigs did not pull hard enough to GND to trigger the amp.? You can? find those? videos yourself. |
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Re: QMX+ failed with power issues on first power up
Hey Mark, Yesterday Infaced the Same issue with my new build QMX+. IC101 was getting hot and the Output voltage die Not reach the 3,3V even with a high dury cycle. In my Case a SMD Diode D105 has fallen of the PCB, seems IT was not soldered correctly. Luckily o found it on the Workbench and after solderimg it in again, everythimg was fine. Check for D105... 73 de John Z via <jdzbrozek=[email protected]> schrieb am Sa., 22. Juni 2024, 18:01:
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Re: QLG3
There¡¯s no doubt GPS receivers are sensitive to switching power supply noise. If my nearby PC is on, QLG2 will never lock but QLG1 will. I don¡¯t know if this is due to a difference in the receiver implementations or if the QLG1¡¯s patch antenna is that much better. With the PC turned off, the QLG1 still locks slightly faster than QLG2. The reason I use QLG1 more is that I raised its data rate to 115,200 baud to allow for faster parsing of the time string. I can¡¯t get the QLG2 to go faster than the default 9600 baud. Tony On Sat, Jun 22, 2024 at 10:09?AM Hans Summers via <hans.summers=[email protected]> wrote:
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Re: QMX+ failed with power issues on first power up
One more thing: Can you tell specifically which components on the 3.3V SMPS are getting hot? It is not clear from your photo. There may be an issue on that module as well. JZ On Sat, Jun 22, 2024, 11:43?AM John Z via <jdzbrozek=[email protected]> wrote:
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Re: QMX+ and 50W QCX Amp
60dbm.com sell the guts of an HR 50 amp all built up on a heat sink for? $120 with? $USD 27 shipping costs.? it needs? 10mW to drive because the put in an extra? RD16HH as an amplifier for the main Quad. It's well worth looking at.? THey also sell the thing fully built up with their? LPF system . you can buy LPF? kits or built up LPFs suitable for? 50 W rf? on Ebay or Ali for? order? 50 USD.? What you don't get is the nice digital interface and tuner hat the HR50 might give you.? 60dBm sells only built up assemblies , no kits.? They have a range from? 10 W out to? 100 W out. I'm not a user of this amp but I know of someone who is and he is very happy with it.? ? TEF? |
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Re: QMX+ dev board question
Hi Mark > Hans...how about MicroPython or Ruby instead of "basic" ?...;-) Yes, various people could make good arguments for all sorts of programming languages.? In my former software development career?I never really minded what language the company required. Maybe I was unusual in this. I always thought once you have a programming mentality, it's more important the logical construction of the application, than particularly what programming language it's in.? Remember?too that we are operating here on relatively small microcontrollers, in terms of the Flash memory available and RAM. It isn't trivial, neither in relation to developing it, nor the resource requirements on the hardware, to write a Virtual Machine and a Programming language and interface it to all the functions of the radio. It so happens that I had already done all that for U4B and I chose BASIC for several reasons; one of which was that I could relatively?simply write a compact and performant implementation?of it and a VM for it to run on. Another key reason was that it's called BASIC for a reason, it's a lot easier to learn, for non software people, than many more advanced languages. Yet you can still accomplish everything you need to do, particularly on a relatively small system like this.? One of my favourite stories in this regard: in 2007-2011 I headed a "Rapid Application Development" team at a large investment bank in London, pricing exotic commodity derivatives. We had a large server estate with 1,000 parallel computer nodes, to which the high intensity simulations got distributed. It was a very complex system. But as we were "Rapid Application Development" we were doing everything with Excel and VBA.? Speed was critical, by which I mean delivery of new deal pricing types etc. Famously the mainstream Commodities IT department had taken 13 months to implement pricing of Asian Barriers but we were able to turn around such demands within 1-2 days. Which was critical because by the time 13 months had elapsed every other bank can also do it already and there is very little money in it. So we were cutting edge and we had to be fast fast fast even though sometimes that involved cutting some corners and taking some risks.? Yet as I said, it all ran on Excel/VBA calling some C++ libraries written by the rocket scientists department (mathematicians). In the end as we were so so so fast, we were doing the official pricing and risk management which used to run for 10 hours overnight on those 1,000 blade computers in the server room. The Excel processes were all kicked off by a scheduling system called "AutoSys" but basically Excel was under huge stress, expected to cope with all that; so it was always failing horribly. When that happened (nearly daily) me or my team had to wake up, log in, and restart it, and sometimes it didn't get finished in time for the market open the following morning, and then we were yelled at by trading who were then trading blind with no risk simulations to rely on. Sometimes we couldn't even get it finished until the SECOND day.? Chronically under budgeted, yet it came to the point where the thing got more and more unreliable, the more and more we got to be the victims of our own success, because more and more complex deals came onto the system. So at some point, tired of being yelled at and all the stress, it came time to urgently find a solution.? Excel/VBA is very close to Visual Basic (VB6 at that time, if I recall). What I did was rewrite the whole system in VB6 instead of Excel/VBA; I single handedly took on the task (as I said, we had no budget, no resources, nothing) so it was a matter of finding a solution, despite having nothing to work with; and in the end I just had to do it myself, alongside all my other responsibilities. So it was critical that VB6 and VBA are the same syntax and similar in many ways.? I completed the whole re-write?in 3 weeks.? Excel still kicked off the process but immediately handed over to the VB6 executable, which did everything. The results were written into a plain csv text file, appended to the file as they came in. Then at the end VB6 signaled to the Excel host that it was finished, and Excel VBA read the results file. So from the user perspective everything looked totally the same, but under the hood, instead of Excel/VBA doing the heavy work, it was handing off to a VB6 executable.? Our problems were completely solved and I didn't get woken up at night at all even ONCE in the following 6 months and neither did any of my team, it was 100% reliable. After that I left UK and went to Japan, so I don't know what happened after that. The .csv results file was super simple and as it was a matter of just appending results as they came in, if there ever was any failure, the VB6 program read all the results it saw in the previous .csv file and didn't need to repeat those calculations; basically it could resume where it had failed and not waste time repeating any calculations.? Success? I thought so. But you can't imagine the barrage of criticism I was in for. Mainly from the mainstream IT departments. Why had I used VB6, not some more advanced programming language? Well because it was similar to VBA, my back was against a wall in a corner, we had to have a solution super quickly, and nobody gave me any development resources or budget or anything, what was I supposed to do, except make the job as small as I could do and sit there all evening doing it myself? Next: why did I use a .csv file? I should be using a proper relational database. Or at least .xml files etc., not plain csv! How low tech was that! Well again - who gave me time or resources, what was I supposed to do, except do it the easiest quickest way I could think of? Not to mention that writing out a huge xml blob is also a non-trivial process and if it fails, things are not properly terminated so there isn't a "resume" option easily available.? Anyway I didn't care about the criticism. I thought it was a great example of KISS (Keep It Simple Stupid), not making anything more complex than it needs to be. As dear old George G3RJV (SK, RIP) was wont to quote from Occam, "it is vain to do with more, what can be done with less".? Sorry for the long waffle. KISS. And I always had a love of simple, BASIC - when I put it in QMX everyone will be able to learn it if they want and do what they want. Or ignore it completely if they wish. The simplicity, compact implementation, low resource demands, are pretty hard to beat!? 73 Hans G0UPL On Sat, Jun 22, 2024 at 6:10?PM Mark Ennamorato via <mark.ennamorato=[email protected]> wrote: Hans...how about MicroPython or Ruby instead of "basic" ?...;-) |
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Re: QMX+ failed with power issues on first power up
The 3.3V SMPS and the 5351 are definitely too hot! An output(s) of the 5351 might be shorted to ground, or the component may have failed. The inductor L201 gives you an opportunity to assess whether the 5351 is drawing too much current. With the power off,? measure the L201 resistance. With the power on, measure the voltage across it and calculate the current through it. That current is the sum of 5351 and TCXO current demand, so you don't have a pure isolated reading.? Still, knowing that the TCXO does not draw much, and checking the spec for 5351, you can get a sense as to whether the current draw is out of bounds or not. Another useful check is to look at clock signals CLK0, CLL1, and CLK2? with a scope and see if the signals are the expected frequency and level. JZ On Sat, Jun 22, 2024, 11:30?AM w8gu via <w8gu=[email protected]> wrote: 3.3v power supply around 50C |
Timothy Fidler
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