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Re: QDX Heat Sink idea? Thermal foam?
ajparent1/kb1gmx
Also to bridge 3-5mm you want aluminum or copper to do that
as most of the heat transfer materials are thing as in under a fraction of a mm. They exist to take care of flat to slightly rough as filler. Radios like Btech use very different devices that have the ability to transfer heat far more efficiently. Allison ------------------------------- Please reply on list so we can share. No private email, it goes to a bit bucket due to address harvesting |
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Re: QDX Heat Sink idea? Thermal foam?
If you took the time to exactly measure the distance from the inside of the case bottom and the PC board, you could cut a copper or aluminum slug to that distance and drill a hole in the center. Then using a longer M3 screw put it in from the top of the board and washer through thu the slug, then carefully slide the board into the bottom track and push the screw through the bottom of the case and secure it with a nut. The height of the slug will need to be fairly precise or you will not get good contact with the board and case or of too small damage the board when tightening. It probably would be a good idea to remove the finish on that small portion of the case bottom for good contact.
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Re: QDX No transmit output power
#qdx
Roger N5RWK
Evan,
I ran the terminal utility again just to make sure I wasn't reading the frequency wrong. Looks to me like it is set correctly: QDX v1_01c
QRP Labs, 2021
+---Configuration------------------------+
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Configuration | TCXO frequency 25000000 |
Audio filter sweep | Sideband USB |
RF filter sweep | Default frequency 7074000 |
Input analysis | Audio gain 5000 |
CAT command test | VOX DISABLE |
Log file | Rise threshold 80 |
Factory reset | Fall threshold 60 |
Update firmware | Minimum cycles 1 |
Exit terminal | Minimum samples 480 |
| Discard cycles 1 |
| IQ mode DISABLE |
| Japanese band limits DISABLE |
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+------------------------Ctrl-Q = Quit---+
So I conclude from this that the QDX is not reading this data properly when it initializes on power up. In other words, I always have to reset to a proper band upon power up. Interesting that it's off by a factor of 1,000 73, Roger N5RWK |
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Re: QDX Heat Sink idea? Thermal foam?
ajparent1/kb1gmx
Those blue silicone thermal tads or the material in sheet form are available.
However the thermal resistance of the plastic case is rather high so the advantage is small. Note the case thermal resistance is 150C/W, translated that means if the die is dissipating 1W of power the die temperature will be 150C hotter than ambient! power devices mount the die to metal tab or flange to get that down to a number like 2.4C/W (IRF510). Solutions, keep the power down and insure the temps never reach that. Allison ------------------------------- Please reply on list so we can share. No private email, it goes to a bit bucket due to address harvesting |
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Re: Si5351A output buffer
ajparent1/kb1gmx
If you use a MMIC (monolithic microwave integrated circuit)...
you do not need a lot of gain as the signal out of the 5351 is nearly 10mW! Thats about 3.3V P-P. So to use a MMIC you need some attenuation to avoid over drive and also select a MMIC that can produce at least 10dBm output (or higher). Most MMICS are not high power out that being greater than 10dBM so select for something much stronger say 23dbm. Class E at 200mhz requires some fancy sillicon good to far higher frequencies. Also maintaining a 200mhz signal as square wave will require more than just COAX as impedance matching at both ends will be critical or you will loose signal and end up with something looking very much sine wave. WHY? Also since most MMICs are good to 1ghz or more a board with a suitable one already designed is advised. Allison ------------------------------- Please reply on list so we can share. No private email, it goes to a bit bucket due to address harvesting |
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QDX Heat Sink idea? Thermal foam?
William Smith
My BTech UV-5R radio has a thick piece of blue foam between the final PA and a nearby heatsink, is there a similar product we could put between the bottom of the case and the final transistors in the QDX? It looks like it should be somewhere between 3.5 and 5.0 mm high, but all I can find at Mouser is:
And the lowest cost piece is an 8"x16" piece 0.160" (4mm) thick for $65, which is at least 128 times the size I need, and it's electrically conductive, etc. Anyone else know what might work to thermally connect the transistors to the case? 73, Willie N1JBJ |
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Ron Starr K0OXB
I mistakenly posted this to K0OXR , It should have been sent to K0OXB. Therefore I am re-posting and hopefully the right person (K0OXB) will do the right thing. Jack, NI8N informed me that you were ignoring his emails also. Too bad, so sad 🙏🙏ing for you ! I’m pretty sure that one of the 10 Commandments is: Thou shall not steal. Please remember that if you are one of the individuals that is religious, and attends religious services. Paul K2DB Ron, I looked you up on QRZ and you do not have an email address. I wanted to take care of this off-line, but you leave me no choice right now. Back on October 10 I purchased a 80 meter QCX + and the 50 W amplifier to go with it. From Jack Hubbard NI8N. On November 11, I received a package from Jack that contained the other 80 meter original QCX that you had ordered. I informed Jack of this mistake, and he apparently mixed up the packages and sent them to the wrong people. Jack informed me that it was you that got the other package. I would appreciate it if you would get a hold of Jack or me and make arrangements for me to get what I originally paid for and you to get what you originally paid for and not stick Jack with the shipping costs and having to refund me money for something that I didn’t get that you did please respond thank you. I certainly hope this is just a mistake and not trying to stick Jack and I and keep something you didn’t buy. Please respond off-line to keep this private seeing that you did not have an email listed. Paul K2DB |
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Re: QDX just stopped receiving
Evan Hand
On Tue, Nov 23, 2021 at 11:23 AM, Andrew Lenton wrote:
do you know how to get a screen shot from terminal?Hi Andrew, I just do a screen print then paste the screenshot in the online message editor that has cropping tools to crop it. Example follows. Just do it with the terminal window open. 73 Evan AC9TU |
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Re: What is the actual "success rate" for home built QCX+ radios?
ajparent1/kb1gmx
As a old school engineer and very active designer...
I have long subscribed to the I build what I want from things I can get (or afford) school of thought. Kits save me hunting for parts, less than half of them get built to plans, most get modded to suit me. Or they get modified to make them work to what I'd call a decent level. They satisfy the something I want but not a commercial built gear often on a tight budget. I also scratch build from my extensive junk box and massive parts stock. I've been doing that for over 50 years. I build everything that includes scopes, test gear, signal sources, radios transceivers, and even antennas from wires to yagis from VLF to upper UHF. Some on stated building as a ladder. I would say appliances are bottom rung the the ladder is tall and kits from simple though very complex fill most of it and scratch build and design are the very upper reaches of the ladder. That same ladder also cover skills needed to accomplish the level of work done. With increasing skills and understanding there is a transition from assembling to building and onto experimenting where understanding is applied. We all climb the ladder to our comfort levels and often expand those. Allison ------------------------------- Please reply on list so we can share. No private email, it goes to a bit bucket due to address harvesting |
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Re: What is the actual "success rate" for home built QCX+ radios?
jjpurdum
Maybe we need another rung on the ladder, above kits: those who do order their own parts, fabricate a PCB or use perf board, and build something from someone else's design. Jack, W8TEE
On Tuesday, November 23, 2021, 12:55:57 PM EST, Bill Cromwell <wrcromwell@...> wrote:
Hello Jack, I have to disagree with those fellows. If I make a "bill of materials" and order them, receive them all in the same box from the post office (or UPS) I don't see how that is different from buying a "kit of parts" and then building the radio (or other device). A "kit" like the uBitX V6..not so much. That is like claiming to have built your own computer after plugging in some boards and turning it on. QRP Labs kits (and others) do require us to build them. If I wanted to be like those two quoted I could say you didn't build anything unless you salvaged all the individual parts from an old TV (even a later flat screen model) or better yet fabricate all of the transistors and ICs (or vacuum tubes) in your garage :) I have done all of the earlier stuff but not fabricated a transistor - not even a large one (nor a tube). I feel that anybody who had to pick and solder parts to build radio gear is on the same playing field as the scratch builder from salvaged and home fabricated parts. YMMV :) 73, Bill KU8H bark less - wag more On 11/23/21 12:01 PM, jjpurdum via groups.io wrote: > Just yesterday I was asked: "Do kits qualify as 'homebrew' equipment?" > Bill Meara (of Solder and Smoke fame) says "No". As many of you know, > Pete Juliano is a regular on Bill's podcasts and is an amazing > homebrewer. Pete's one of those guys you could send into a forest with > a stick and a rock and he'd emerge a few days later with a complete > 5-band transceiver capable of 20W on all modes. Look at Dave Richards > site for homebrewing elevated to an art form: > Inline image > Alas, I don't have the skill set to do something like that and I truly > envy those who do. > > My answer was that homebrewing is not a discrete point in space. > Rather, it's a ladder with commercial rigs at the base (after all, you > still have to connect things!), kit building is one rung up, with Pete > and Dave's homebrewing skills are at the top. Still, I agree with > James that anything from "kit building" on up simply gives one a > measure of enjoyment that you just can't experience/appreciate with > commercial gear. > > Jack, W8TEE > > On Tuesday, November 23, 2021, 11:34:25 AM EST, KB9NBL > <mtminstr@...> wrote: > > > Keith, > Thanks for the question. > I believe there is no way to know how many just sit or are squirreled > away in a backpack waiting for the next camping trip. > > I have built a 40 meter QCX Mini and 80 meter QCX Plus > Except for me shorting the mini screen and replacing it without > issues, they worked perfectly on first power up. > > I use them everyday. I was off the air for over 20 years and the > QRP-LABS radios and other kits from them are the first I built after > my hiatus. > There is just something in "Roll'in your own" that a ready made boxed > radio can't give. > Yes, I do have other radios, but building, learning and contacting > others with low power has a satisfaction that nothing else could give. > > IMHO I believe the vast majority, 87%, are used regularly. > It really is a good question. > > Regards > 73 > James > > |
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U3S Frame parameter 120?
KI7MWA
I have my U3S, with relay switched LPF set with the Frame parameter set to 60, and the Start parameter set to 6. Thus, after the U3S has coordinated with the GPS, it starts transmitting at 6 minutes after the hour, every hour. With 6 bands, at 2 minutes each, plus the frequency calibration, it is done with its business at about 25 minutes after the hour. Just wondering if anyone has tried a frame of 120, which would (logically) result in transmitting every 2 hours. Don't want to fool around with it if someone else has tried (and failed) with this.
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Re: QCX Mini CW Filter
#qcxmini
Derek Eells
Reiner,
Thanks very much! Somewhat comforting to know yours is high also. I still need to check my component values but maybe I will redo it with 530hz resistors to get closer to the 550hz I want. Thanks, -Derek |
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Re: What is the actual "success rate" for home built QCX+ radios?
Bill Cromwell
Hello Jack,
toggle quoted message
Show quoted text
I have to disagree with those fellows. If I make a "bill of materials" and order them, receive them all in the same box from the post office (or UPS) I don't see how that is different from buying a "kit of parts" and then building the radio (or other device). A "kit" like the uBitX V6..not so much. That is like claiming to have built your own computer after plugging in some boards and turning it on. QRP Labs kits (and others) do require us to build them. If I wanted to be like those two quoted I could say you didn't build anything unless you salvaged all the individual parts from an old TV (even a later flat screen model) or better yet fabricate all of the transistors and ICs (or vacuum tubes) in your garage :) I have done all of the earlier stuff but not fabricated a transistor - not even a large one (nor a tube). I feel that anybody who had to pick and solder parts to build radio gear is on the same playing field as the scratch builder from salvaged and home fabricated parts. YMMV :) 73, Bill KU8H bark less - wag more On 11/23/21 12:01 PM, jjpurdum via groups.io wrote:
Just yesterday I was asked: "Do kits qualify as 'homebrew' equipment?" Bill Meara (of Solder and Smoke fame) says "No". As many of you know, Pete Juliano is a regular on Bill's podcasts and is an amazing homebrewer. Pete's one of those guys you could send into a forest with a stick and a rock and he'd emerge a few days later with a complete 5-band transceiver capable of 20W on all modes. Look at Dave Richards site for homebrewing elevated to an art form: |
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Re: Si5351A output buffer
HF
Hi Richard,
I use a 74ACT04 gate. It boosts the drive for the BS170s in my U3S. But i's only good up to around 60 MHz, and I'd like to go higher. I'll be curious to know which MMIC you end up using and how well it works if you go that route. Cheers Halden VE7UTS |
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Re: QCX Mini CW Filter
#qcxmini
I checked my maximum again, it is 575Hz, should be 530Hz. That is also about 10% difference. The values of the C's can also differ, as they often have a greater tolerance
73 Reiner |
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Re: QDX just stopped receiving
Hi Alan, 4 | **************************************************************. . . . . . . | * . *** * . ** | * . ** *. * * * . * |* . ** **** * . ** * **** . ** -20|*. . . . . . . . **. .*. .*. . . . * ... . **. . . .*. .*...** . . .*.** . . |* ** ** .* * * * . ** * *.* * ******* |* * * * * .* * * . * ** *** * * ** * |* ** *** * . * . ** * ** * * -40| .*. **. . . * . ... . . . . . . . . ... . . . . . . . . .*. . * . . . . . . | * * . . . |* * . . . |* . . . -60| . . . . . . . . ... . . . . . . . . ... . . . . . . . . ... . . . . . . . . | . . . | . . . | . . . -80| . . . . . . . . ... . . . . . . . . ... . . . . . . . . ... . . . . . . . . | . . . | . . . | . . . -100 . . . . . . . . ... . . . . . . . . ... . . . . . . . . ... . . . . . . . . ---------------------------------------------------------------------------- 100 1000 2000 3000 3850 Ctrl-Q: Quit - Band down + Band up BAND: 80m USB LSB
5 | ************************************************************** 0 | * . . . . . . . ... . . . . . . . . ... . . . . . . . . ... . **. . . . . . | * . . . ** | * . . . * |* . . . * -20|*. . . . . . . . ... . . . . . . . . ... . . . . . . . . ... . . . . * . . . |* * . * . . * |* * * . * ** ***** . * |* * ** . ** * *** .* * * . * -40| . . . . * .*.*. ..**. . . ****. * . ..**.*. . .*.*. . .**.. . . . . .*. .*. | * * *** * . ** ** *** * * * * ******* * | * * * * . * * * * .* * * ** **** * | * *** * . * * . ** * *** -60| **.** . . . . . ... . . . . . . . . ... . . . . . . . . ... . . . . . * .** | ** . . . * |* . . . |* . . . -80|*. . . . . . . . ... . . . . . . . . ... . . . . . . . . ... . . . . . . . . |* . . . | . . . -99| . . . ---------------------------------------------------------------------------- 100 1000 2000 3000 3850 Ctrl-Q: Quit - Band down + Band up BAND: 40m USB LSB 6 | ************************************************************** 0 | * . . . . . . . ... . . . . . . . . ... . . . . . . . . ... . **. . . . . . | * . . . ** |* . . . * |* . . . * -20|*. . . . . . . . ... . . . . . . . . ... . . . . . . . . ... . . . . * . . . |* . . . * |* . . . * | . . . * -40| . . . . . . . . ... . . . . . . . . ... . . . . . . . . ... . . . . .*. . . | . . . * | . . . * | . * ** . * -60| . ***** . .*. . ..* . .*****. . . * *.**. .*. .** .** .*... * .*. . . * . . | * * ** ** * * ** ** ** **. *** *** * * ** **** ** * * * * | ** ** * * ***. * * * ** * . * * * . * ** * **** * | * * . . * * . * * *** -80|*. . . . . . . . ... . . . . . . . . ... . . . . . . . . ... . . . . . * **. |* . . . * |* . . . -98| . . . ---------------------------------------------------------------------------- 100 1000 2000 3000 3850 Ctrl-Q: Quit - Band down + Band up BAND: 30m USB LSB 13 | *************************************************************** | * . . . * 0 | * . . . . . . . ... . . . . . . . . ... . . . . . . . . ... . . **. . . . . | * . . . * |* . . . * |* . . . * -20|*. . . . . . . . ... . . . . . . . . ... . . . . . . . . ... . . . . * . . . |* . . . * |* . . . * | . . . * -40| . . . . . . . . ... . . . . . . . . ... . . . . . . . . ... . . . . .*. . . | . . . * | * . * . . * | * * ** * * . * * . * -60| . * . * * *** . *..*. **. * . . * **... .*.*.*.***.*. . *.. . . . . . * . . | ** * * ****. * * * ** * * *** * ** * * **** * * * * | * * . * * ** * * *. * * * ** * * |* . * * * . *** * * **** -80|*. . . . . . . . ... * . . .*. * . . ... . . . . . . . . ... . . . .*.****** |* . * * . . **** -91|* . . . ---------------------------------------------------------------------------- 100 1000 2000 3000 3850
Ctrl-Q: Quit - Band down + Band up BAND: 20m USB LSB |
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Re: What is the actual "success rate" for home built QCX+ radios?
jjpurdum
Couldn't agree more with John's list: 1) Anyone who tries to build any kit without reading the instructions at least once is doomed, and 2) I'm done with lead-free solder. I use 62/36/2 solder (tin/lead/silver from Radio Shack and still available online) exclusively and find that anything above 0.025" is a pain to work with. I did buy some 0.015" solder but, honestly, it seems to evaporate under heat. The Radio Shack solder is 0.022". Jack, W8TEE
On Tuesday, November 23, 2021, 12:09:34 PM EST, R. Tyson via groups.io <tysons2@...> wrote:
On Tue, Nov 23, 2021 at 02:53 PM, John Terry (W0JDT) wrote: When I read about all these glowing successes, I tend to feel somehow inferior or inadequate that I can't match that performance, but a don't think it is true. I reckon most are telling the truth. Key ingredients.. Read the instructions and understand them. Some previous experience of soldering and gaining good results. Check each component is what you think it is and put it in the right place. Examine every solder joint after making it by using a jewellers loupe or similar. Use a good quality solder, there are many inferior types on Ebay. Using a suitable soldering iron with a fine tip size. If the above requirements are met then why wouldn't it work ? Admittedly there were some initial setbacks with faulty components fitted to the mini boards but this was quickly rectified by Hans and was down to shoddy work by the board manufacturer. They were quickly replaced by a different supplier with good quality standards. Reg G4NFR |
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Re: What is the actual "success rate" for home built QCX+ radios?
jjpurdum
Just yesterday I was asked: "Do kits qualify as 'homebrew' equipment?" Bill Meara (of Solder and Smoke fame) says "No". As many of you know, Pete Juliano is a regular on Bill's podcasts and is an amazing homebrewer. Pete's one of those guys you could send into a forest with a stick and a rock and he'd emerge a few days later with a complete 5-band transceiver capable of 20W on all modes. Look at Dave Richards site for homebrewing elevated to an art form: Alas, I don't have the skill set to do something like that and I truly envy those who do. My answer was that homebrewing is not a discrete point in space. Rather, it's a ladder with commercial rigs at the base (after all, you still have to connect things!), kit building is one rung up, with Pete and Dave's homebrewing skills are at the top. Still, I agree with James that anything from "kit building" on up simply gives one a measure of enjoyment that you just can't experience/appreciate with commercial gear. Jack, W8TEE
On Tuesday, November 23, 2021, 11:34:25 AM EST, KB9NBL <mtminstr@...> wrote:
Keith, Thanks for the question. I believe there is no way to know how many just sit or are squirreled away in a backpack waiting for the next camping trip. I have built a 40 meter QCX Mini and 80 meter QCX Plus Except for me shorting the mini screen and replacing it without issues, they worked perfectly on first power up.
I use them everyday. I was off the air for over 20 years and the QRP-LABS radios and other kits from them are the first I built after my hiatus. There is just something in "Roll'in your own" that a ready made boxed radio can't give. Yes, I do have other radios, but building, learning and contacting others with low power has a satisfaction that nothing else could give. IMHO I believe the vast majority, 87%, are used regularly. It really is a good question. Regards 73 James |
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Re: What is the actual "success rate" for home built QCX+ radios?
R. Tyson
On Tue, Nov 23, 2021 at 02:53 PM, John Terry (W0JDT) wrote:
When I read about all these glowing successes, I tend to feel somehow inferior or inadequate that I can't match that performance, but a don't think it is true. I reckon most are telling the truth. Key ingredients.. Read the instructions and understand them. Some previous experience of soldering and gaining good results. Check each component is what you think it is and put it in the right place. Examine every solder joint after making it by using a jewellers loupe or similar. Use a good quality solder, there are many inferior types on Ebay. Using a suitable soldering iron with a fine tip size. If the above requirements are met then why wouldn't it work ? Admittedly there were some initial setbacks with faulty components fitted to the mini boards but this was quickly rectified by Hans and was down to shoddy work by the board manufacturer. They were quickly replaced by a different supplier with good quality standards. Reg G4NFR |
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Re: What is the actual "success rate" for home built QCX+ radios?
On Nov 23, 2021, at 8:34 am, Rick McGaver via groups.io <nk9g@...> wrote: Rick, NM0S, the ham who designed them, is selling them on eBay in a sturdy case for $50 plus shipping. https://www.ebay.com/itm/255043537914 Looks like I triggered some interest in it. Six have sold in the last 24 hours. You can find the manual and schematic for the discontinued Four State QRP Group version here: http://www.4sqrp.com/QRPometer.php —Mike Perry, WA4MP On Nov 23, 2021, at 8:17 AM, JUSTIN R "RANDY" PADAWER - K7RAN via groups.io <padawer@...> wrote:_._,_._,_ |
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