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Re: No output QCX 40 output drains show 1.6 watts in receive
George Korper
Yes, I will take another look this morning, but I see a small hole in the top of IC1 under magnification. So I will send it over tp AZ for a second opinion. When the next QCX gets here I have decided to assemble in several better ways for my manner of operation, including better solder, sockets for iIC's and an enclosure. Gracias Amigo. Oh, and a new respect for voltage measurement.
On Thu, Dec 12, 2019 at 6:48 AM Alan G4ZFQ <alan4alan@...> wrote: > Game over as I don't have a replacement for IC3.
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New kit: 50W PA for QCX
Hans Summers
Here is a new kit, this is a 50W PA kit for the QCX. See http://qrp-labs.com/50wpa . Price is $29.50 (approx £22 or 26€) which includes the PCB, all components and connectors, and two large black anodized aluminium heatsinks. The amplifier produces up to 50W power with full break-in (QSK), with 20V 5A supply. At 13.8V supply on 40m CW the measured power output is 25W. A beautiful enclosure for it is also available, price $16 (approx £12 or 14€), see http://qrp-labs.com/50wpabox . It is made from black anodized extruded aluminium with front and rear panels drilled and printed to match the 50W PA. A key feature of the kit is fast solid-state transmit/receive switching (relays!) - which allows full break-in (QSK) operation using the QCX. The kit can be built for 40, 30 or 20m bands, which covers 90% of QCX kits. It can also be built for other bands if you supply your own Low Pass Filter components. Multi-band would be possible if you connect your own switched external Low Pass Filters. Please refer to the FAQ on the 50W PA page http://qrp-labs.com/50wpa if you have any questions. The 68-page manual is very detailed making construction un-daunting, and the manual also also includes a substantial section detailing the circuit theory. Despite our dedication to QRP (5W and under), there are occasions when a bit more power is needed, and this kit provides it. For example, you want to QSO a particular station on a sked at a particular date and time; or when conditions are poor, or you want to work particular DX... any number of reasons. During the summer of 2019 the 40m version of this amplifier was tested extensively here in QTH KM46, with well over 500 QSOs in the log. Despite the poor band conditions and my very mediocre antenna and location, QSOs ranged from New Zealand and Japan in the East, to US in the West; Finland in the North, down to Saudi Arabia and everywhere in between. (500+ real QSOs averaging 10 minutes, not contest exchanges). During QSOs I estimate around 90% of correspondents are using power in the 50-100W range, the remaining 10% operate with higher power than that or a few of them, with QRP (5W and below). This 50W PA kit puts you and your QCX on a level playing field with the majority of CW operators on the bands. So pimp your station, pump up the watts... have some fun with a new project... the 50W PA kit http://qrp-labs.com/50wpa 73 Hans G0UPL
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yahoo group changes
SkipF, NT1G <skip.flem@...>
QRPLABS is NOT a YAHOO group.. It's like driving a Mercedes and Chevrolet says they are dropping your warrentee. Whoop Dee Doo.
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Re: yahoo group changes
Hans Summers
toggle quoted messageShow quoted text
On Thu, Dec 12, 2019 at 11:00 AM Martin <m.sellschopp@...> wrote: Hi,
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Re: yahoo group changes
Martin DK3UW
This is the mail I got
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yahoo group changes
Martin DK3UW
Hi,
I just got a disturbing mail from Yahoo. If I understand correctly all content of our group will be deleted and the group will become something not open to public. Exchanges only be e-mail and new menbers only by invitation. To me that looks like the end of our communication and as if all the usefull information stored in the history of this group to disappear. Any remedy or chance to move the group somewhere else ? 73's Martin
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Re: LightAPRS-W (WSPR) Tracker
Mustafa Tan
Hi Tim, LightAPRS-W does not go sleep as much LightAPRS. It's because WSPR preparations and TX. WSPR TX takes 2 minutes and preparations starts 1 minute before. So no sleep nor APRS TX during this period. // preparations for HF starts one minute before TX time at minute 3, 7, 13, 17, 23, 27, 33, 37, 43, 47, 53 or 57. No APRS TX during this period... if (readBatt() > WsprBattMin && timeStatus() == timeSet && ((minute() % 10 == 3) || (minute() % 10 == 7)) ) {
On Thu, Dec 12, 2019 at 7:19 AM Tim Wiwel <tim.wiwel@...> wrote: Mustafa: --
Mustafa Tan https://picoballoon.ist
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Re: No output QCX 40 output drains show 1.6 watts in receive
Alan G4ZFQ
Game over as I don't have a replacement for IC3.George, OK, although they should be easy to source. But I am thinking that further faults may be found if the voltages are checked. Maybe look at again sometime, you learn more about how something works when it does not work! 73 Alan G4ZFQ
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Re: Two QCX kits (80m and 40) - both with shorts on Si5351A - fixed
ajparent1/KB1GMX
one last thing... soldering iron.
The average one I see in use by people is a reasonable quality temperature controlled unit turned too far up with a cruddy tip with rough edges. Replace the tip turn it down and try to not use the tip as a chisel. Hint put it back in the holder without cleaning it after making a joint. Clean it on the way out and make sure its shiny clean before touching the joint. If it gets dark and grungy too fast its likely way to hot. Or an el cheapo that run at 900 degrees or hotter, with a cruddy black tip. Get a soldering iron! Both users tend to have terrible soldering and complain they can't get the solder to melt and they burn up boards in the process. The tip has to be clean to transfer heat. If you beat it up or use poor solder and high heat (trying to get it to work) that tends to destroy tips amazingly fast. I've see a few kill a tip in hours. I tend to use tips for literally thousands of hours (years) of build time. Quality solder, good care, and moderate temps. I bought the current Weller WES51 some 20 years ago and the current tip is more than 3 years old. The only thing was to repair the cord to the handle. My other iron is a really old TCP60 (curie point temp control) from about 1979ish, the .25" wide tip on that is maybe 10 or more years old. I use that for SMT parts as its wide! ------- Please reply on list so we can share. Off list email goes to trash, I had to due to scrapers.
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Re: LightAPRS-W (WSPR) Tracker
Tim Wiwel
Mustafa:
I just received my tracker and am very impressed. Looks great. Very easy to get running. Doing power measurements, the unit never draws more then about 320-350mA with Vbat at 7.4v or 5.5v. DRA pin 7 is low. On total power consumption, the unit only goes to sleep (10mA) about 3 minutes in 10. It consumes 40mA almost always with 350mA during the 2s ARPS transmission. Does this seem correct? I see 3 APRS transmissions in 10 minutes. These tests were preformed with no debug, no USB cable, a 19in wire connected to the VHF antenna, at about 21C using a Fluke 83 Meter. Before I hack on the code, is there a simple Si5351 tuning program? We plan to do a test flight next Thursday, 19 Sep using my call sign. Tim, KM4EFW Tim.
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Re: Two QCX kits (80m and 40) - both with shorts on Si5351A - fixed
ajparent1/KB1GMX
What did you use?
I do not advise using any of the no-lead solders. They do not rework well and generally need more heat. More pain that gain. The standard here in my lab is the same for the last 40+ years Kester 44, 37/63 SN/PB alloy in .031" diameter. I also use the .020 and .040 diameter of the same at any given time I have all three sizes in 1pound spools on the shelf. Its not cheap. KESTER part number 24-6337-0027 An alternate some use is the 245 no clean in the .031 63/37 also kester. https://www.amazon.com/Kester-24-6337-0027-Solder-Alloy-Diameter/dp/B0149K4JTY/ref=pd_cp_328_1/130-0155267-6249125?_encoding=UTF8&pd_rd_i=B0149K4JTY&pd_rd_r=1601493a-5f26-41c2-9b3c-65ccfb1d8bc2&pd_rd_w=iS80j&pd_rd_wg=98Cqk&pf_rd_p=0e5324e1-c848-4872-bbd5-5be6baedf80e&pf_rd_r=6MGM1H1D328D9YW4MACZ&psc=1&refRID=6MGM1H1D328D9YW4MACZ -- Please reply on list so we can share. Off list email goes to trash, I had to due to scrapers.
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Re: Two QCX kits (80m and 40) - both with shorts on Si5351A - fixed
George Korper
Allison, I built my last QCX with poor quality solder and had excessive sputtering and was not satisfied with it. Please recommend a solder that you have had good performance with. Preferably available on Amazon. George
On Wed, Dec 11, 2019, 9:29 PM ajparent1/KB1GMX <kb1gmx@...> wrote: Us old farts that have been in the industry for 30 or 50 years have seen it.
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Re: Beware Buck converters
I use LM2596 DC to DC converters all the time. Their performance is dependent upon load… so beware!
Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ
Owner - Operator Big Signal Ranch – K9ZC Staunton, Illinois
Owner – Operator Villa Grand Piton – J68HZ Soufriere, St. Lucia W.I. Rent it: www.VillaGrandPiton.com
Moderator – North American QRO Group at Groups.IO.
email: bill@...
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Re: Two QCX kits (80m and 40) - both with shorts on Si5351A - fixed
ajparent1/KB1GMX
Us old farts that have been in the industry for 30 or 50 years have seen it.
Its common to hand soldered items. You have to be looking for it.... Solder with internal flux can often spatter. It happens more so with some fluxes and a hotter [than needed] irons as the flux heats up and goes from solid to gas and the solder with it. That sputter can end up everywhere and anywhere. That with modern tight lead spacing and traces close to each other often shows as hairline shorts. Little heat or solvent often breaks them. This is less common with wave soldering, radiant heating, and IR heated SMT soldering systems as there is less solder and the flux is not inside it. That added to the thermal ramp to heating and cooling tends to avoid this. Allison -- Please reply on list so we can share. Off list email goes to trash, I had to due to scrapers.
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Re: Beware Buck converters
ajparent1/KB1GMX
They are real. Likely your asking them to do something they are not happy
with as supplied. I have a bunch of them loose (spares) and more in service. However I took the time to do two things optimize the inductor (inductance and type for the current) and add two resistors to an external pot so its range is limited to a narrow span. The problem is the inductor size has to scaled for the current and voltages or the efficiency goes down and the switching frequency gets pushed around to the limits to try and regulate. Switching regulators are not universal in nature though they often exceed expected performance. If the inductor is not the right inductance they can go into a discontinuous mode and the external switching frequency is the skipped cycles. You see that if they optimized for 2-3A and actually delivering maybe 100-150ma. Its a likely bet the current required by the QCX and U3S is too low for the regulator to be efficient. My QCX the TI part is running at 350khz and at the design center but then again I did what the data sheet said and replaced the inductor. The efficiency is 92% and 14V and 87% at 9V (measured). With the inductor they supplied it would not regulate at all well and efficiency was below 70%. Full datasheet included for the LM2596, ------------------- Please reply on list so we can share. Off list email goes to trash, I had to due to scrapers.
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Re: Beware Buck converters
Phil N6WKZ
Sverre, I tested one of mine and found: 78 mv ripple at 68 KHZ. I guess that mine is a fake LM2596 too. Probably most of those $1.00 Buck converters are fake. Thanks for the link! I used the same setup as in the link. 73 Phil N6WKZ
On 12/9/2019 12:04 AM, Sverre Holm
wrote:
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Re: Two QCX kits (80m and 40) - both with shorts on Si5351A - fixed
Nick Austen
Hi Geoff
The stray resistor leg was one still floating around after clean-up - I have been building electronics things on and off for about 45 years :) I had enjoyed the kit for about 24 hrs - and, through lack of self discipline, was listening to 40m on the QCX while cleaning up :) - a discarded lead was accidentally projected into the air and down onto the kit. Thanks for reiterating the issue of meter voltages and their potential to cause damage. I typically use a CRO first and should take more case with the meter. Interesting to note that for my cheap "Micron" (no-name) meter, I measure the following voltages across the probes for the selected resistance range settings:
Thanks. Nick VK6FABE
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Re: Two QCX kits (80m and 40) - both with shorts on Si5351A - fixed
Arv Evans
Hans Unfortunately it is impossible to perform quality control on assembled kits at the purchaser's location. Also probably impossible to perform knowledge tests on those assembling the kits. Even Heathkit never found a solution to assembler introduced problems. With over 8000 workinking kits out there it would seem that the design is solid. Quality of shipped kits must be relatively good or the units would not be this popular. Arv
On Wed, Dec 11, 2019, 2:11 PM Hans Summers <hans.summers@...> wrote:
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Re: Two QCX kits (80m and 40) - both with shorts on Si5351A - fixed
Nick Austen
Hi Hans
All understood and appreciated. I was obviously unlucky and hope that I am the only one :) Just thought it could help someone else - as, although I was disheartened (still excited like a young boy when the kit is completed), the solution was quick and simple. On the previous kit, I was initially daunted at the prospect of trying to replace the the match-head size 10-lead surface mount device - but did it twice and it was relatively easy. Thanks again, Nick VK6FABE
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Re: New qcx build, and problems
Dave Edwards
Got mine many years ago. But I checked.....you can get small
spools on Amazon, for a fair price. Yellow, green, red on this page, Here is my transformer. I used kaptan tape to hold the start and
end of the big winding, alternate two colors so I could better see
what I was doing when pushing the wires into their correct locations. Forgot to
remove the tape, but...doesn't matter...just looks messy!!
On 12/11/19 4:51 PM, SkipF, NT1G wrote:
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