Re: I ordered a replacement QCX kit.
Hi, Steve
My last job for 25 years featured a WTCP iron that came on with
the bench at 7:30 AM and went off at 5:30 PM six days a week. If I
had to desolder something I'd crank up the one with the hollow tip
and the vacuum pump. 3 or 4 700 degree tips a year, a magnetic
switch every 3 or 4 years, and maybe once in a decade a heating
element. I had one heating element short out and blow the
secondary fuse. Otherwise they just kept on trucking. I did
everything from flyback transformers to .025 pitch camcorder
flatpacks with them. You just needed the long skinny tip for the
SMD's.
73
Jim W4JED
On 4/28/19 12:51 PM, Steve Johnston via
Groups.Io wrote:
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On PC boards with very tight spacing between components, or
especially those with plated-through holes, it can be challenging
to remove parts.? I can do it, but I have many years of experience
and good tools.? Even so, it often makes more sense to just cut
out the wrong/failed part leaving as much lead length above the
board as possible and tack solder the new part in place onto those
lead stubs. You have to have a steady hand and a quick touch with
a good iron.
For those interested in soldering techniques... I've mentored
electronic technicians for over thirty years and have seen a
couple common issues come up:
First problem is using a soldering iron that doesn't get hot
enough or runs too hot. Around 700 deg F is usually a good
target.? Poor heat control is a common issue with irons that plug
into the wall directly rather than soldering stations with a power
supply.? Also it is important for an iron to have enough mass to
hold heat as you solder or desolder a joint.?
I favor the Weller "temperature-controlled" line of soldering
stations with slender conical tips.? The WTCP and WTCPT stations
are available used on eBay for good prices.? Ordering a new tip is
wise when buying a used station.? Tips and replacement parts are
still available from many sources. The best performance to cost
ratio for new stations seems to be the WTCPT model which is very
similar to the older WTCP.? I've been told that the Hakko stations
are good too, but I've not tried them.? Fancy adjustable
temperature and digital readout stations can also be had, but
controls are no substitute for the basic need to be able to hold
enough heat to do a good job.
I've also seen a lot of problems lately with the "Lead-Free"
solder.? I believe it is much better to continue to use the real
Kester 60/40 or 63/37 lead and tin solder.? It works better even
on modern equipment built with lead-free solder at the factory.
Here's an old article that may be helpful:
73? Steve WD8DAS
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Re: ULTIMATE 3S use as CW transmitter
#u3s
That is correct, the modification does not work properly in v3.12a. The last time it did work seems to be v3.09, so yes, it has been a very long time awaiting a fix.?
Also, I agree, the VFO version cannot do beacon modes. I think there is a long list of requests on Hans, many from me hihi.
73 Ken g4apb?
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Re: No TUNE mode U3S ver 3.12 (a)
Hi I just saw post about this. I tried playing with ptt delay but no joy.
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u3s firmware upgrade now tune function not working
#u3s
Hi I recently had to upgrade firmware to v3 12a after an accident with 12v. It all works fine but pressing the right button puts it into a cal process and then will tx at the correct time. The button edits ok. Has anyone come across this? I have just ordered a new chip. 73s G8LDJ
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Andy
As you know the U3S has some nice RF filters. While one could question how well they reject UHF, I would first look for other ways UHF could escape. Maybe the power connection or other things you added. Anyplace to ground that only has an electrolytic capacitor, try adding a good .1 or .01 uF cap in parallel, if there is none. See if it varies with RF, including tuning the frequency setting way up. Also see if interference happens while transmitting into a dummy load. Idea is to see if it is escaping not via antenna, or not related to intended transmit signal.
Curt
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All u3s are in the official case, the TVI at my own location has stopped, maybe the signal quality was down this morning, I didn't check on the TV settings, but whilst the interference was being observed I turned the u3s off and interference stopped immediately.?
On the screen shots, there is a lot of mush around half a meg either side of the wspr frequency but at -70db, the 68th harmonic of 30m wspr is bang on the frequency of the channels that had interference.?
Next check is to scan around there, 689mhz to see what is happening.?
Andy
--
The universe is made up of Protons, Neutrons, Electrons but contains only one M0RON.
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Re: I ordered a replacement QCX kit.
I couldn't agree more with Steve.Gary W0CKI,OP since 1954
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-----Original Message-----
From: Steve Johnston via Groups.Io <sbjohnston@...>
To: QRPLabs < [email protected]>
Sent: Sun, Apr 28, 2019 10:52 am
Subject: Re: [QRPLabs] I ordered a replacement QCX kit.
On PC boards with very tight spacing between components, or especially those with plated-through holes, it can be challenging to remove parts.? I can do it, but I have many years of experience and good tools.? Even so, it often makes more sense to just cut out the wrong/failed part leaving as much lead length above the board as possible and tack solder the new part in place onto those lead stubs. You have to have a steady hand and a quick touch with a good iron.
For those interested in soldering techniques... I've mentored electronic technicians for over thirty years and have seen a couple common issues come up:
First problem is using a soldering iron that doesn't get hot enough or runs too hot. Around 700 deg F is usually a good target.? Poor heat control is a common issue with irons that plug into the wall directly rather than soldering stations with a power supply.? Also it is important for an iron to have enough mass to hold heat as you solder or desolder a joint.?
I favor the Weller "temperature-controlled" line of soldering stations with slender conical tips.? The WTCP and WTCPT stations are available used on eBay for good prices.? Ordering a new tip is wise when buying a used station.? Tips and replacement parts are still available from many sources. The best performance to cost ratio for new stations seems to be the WTCPT model which is very similar to the older WTCP.? I've been told that the Hakko stations are good too, but I've not tried them.? Fancy adjustable temperature and digital readout stations can also be had, but controls are no substitute for the basic need to be able to hold enough heat to do a good job.
I've also seen a lot of problems lately with the "Lead-Free" solder.? I believe it is much better to continue to use the real Kester 60/40 or 63/37 lead and tin solder.? It works better even on modern equipment built with lead-free solder at the factory.
Here's an old article that may be helpful:
73? Steve WD8DAS
|
Re: I ordered a replacement QCX kit.
On PC boards with very tight spacing between components, or especially those with plated-through holes, it can be challenging to remove parts.? I can do it, but I have many years of experience and good tools.? Even so, it often makes more sense to just cut out the wrong/failed part leaving as much lead length above the board as possible and tack solder the new part in place onto those lead stubs. You have to have a steady hand and a quick touch with a good iron.
For those interested in soldering techniques... I've mentored electronic technicians for over thirty years and have seen a couple common issues come up:
First problem is using a soldering iron that doesn't get hot enough or runs too hot. Around 700 deg F is usually a good target.? Poor heat control is a common issue with irons that plug into the wall directly rather than soldering stations with a power supply.? Also it is important for an iron to have enough mass to hold heat as you solder or desolder a joint.?
I favor the Weller "temperature-controlled" line of soldering stations with slender conical tips.? The WTCP and WTCPT stations are available used on eBay for good prices.? Ordering a new tip is wise when buying a used station.? Tips and replacement parts are still available from many sources. The best performance to cost ratio for new stations seems to be the WTCPT model which is very similar to the older WTCP.? I've been told that the Hakko stations are good too, but I've not tried them.? Fancy adjustable temperature and digital readout stations can also be had, but controls are no substitute for the basic need to be able to hold enough heat to do a good job.
I've also seen a lot of problems lately with the "Lead-Free" solder.? I believe it is much better to continue to use the real Kester 60/40 or 63/37 lead and tin solder.? It works better even on modern equipment built with lead-free solder at the factory.
Here's an old article that may be helpful:
73? Steve WD8DAS
|
Very good but what are you showing us.
If the interference is on UHF TV digital signals, then set the
spectrum analyser to look at those frequencies ( 500 - 700MHz
depending on your local channels multiplexes? ) and then scan both
with the suspected unit powered off and again with the unit on.
On 28/04/2019 16:20, M0RON wrote:
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Couple of screenshots from SDRuno, one of the 30m band and the
other of a 10mhz chunk of spectrum including 30m.
--
The universe is made up of Protons, Neutrons, Electrons but
contains only one M0RON.
|
With the change from Analog to digital television much of the interference-to-TV problem
went away.? Partly because it is now more difficult for TV viewers to identify interference
as coming from an amateur radio source, and partly because the digital TV reception is
either adequate for decoding of the bit stream, or is inadequate and causes the TV to go
to a blank screen.? My own U3 and U3S do not seem to cause TVI, but TV signals in this
area are quite strong.? If I lived in a weak signal area (or if my TV antenna and lead-in
were faulty) I would expect that some interference might be present.?
Some of the old-school methods to reduce TVI may be applicable.?
While somewhat dated relative to today's digital TV, the ARRL references may provide some
ideas for where to start with "hardening" your TV from external interference.? Obtaining a stronger
TV signal may be the first place to start.?
My own U3 and U3S units are in metal boxes which may account for the lack of TVI problems.?
Power to these units is bypassed with 0.1 MFD and 22 MFD capacitors right at the power
connector.?
Arv _._
One u3s cause tvi on 40,30 and 20m, tx into an inverted L 5m high around 25m long. Antenna wire runs within 1m of TV antenna.?
2nd u3s loaned out at a different location on 20 and 40 into a long wire but not near a TV antenna also causes tvi.
3rd us3s, also loaned out at another different location is to be tested.
I have a sdrplay duo sdr which covers up to 2GHz, I'll check tomorrow for harmonics and also tx into dummy loads.
--
The universe is made up of Protons, Neutrons, Electrons but contains only one M0RON.
|
Couple of screenshots from SDRuno, one of the 30m band and the other of a 10mhz chunk of spectrum including 30m.
--
The universe is made up of Protons, Neutrons, Electrons but contains only one M0RON.
|
Re: ULTIMATE 3S use as CW transmitter
#u3s
to KEN G4APB,?Does this modification not work in firmware 3.12a???It is a pity that it is so.
Let's wait for the next version of the firmware, but probably it will take a long time to wait.
VFO no not fit there is no beacon function
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Re: I ordered a replacement QCX kit.
I agree with Curt M, and I measured each resistor before inserting, checking (like Santa) everything twice.? I really can not read the color code anymore.? Before starting, I organized all the parts into groups where each group was the same type and value.? Then, I happily found that the Manual has me inserting parts by groups of same type and value.? I also measured the caps, having a cheap cap/coil tester.? And double check the correct location.? I managed to mis-place only one part in my construction, and I realized it when I needed those holes for another part... Oh well.? And I needed to add the five turns to T1.? I would change the manual to add the extra five, then make allowance to bypass, because it is easier to remove turns than to add.? I am happy to say that my build worked right away without any other mods.??I bought the commercial enclosure and hope to be taking the rig out on SOTA and such this year.? ?
Bottom line is to measure each part before inserting, check twice before soldering.? Think of it as a classroom "test".? But if you don't get 100%, you fail.? And there are over 100 parts to solder, I think.??
73, Joe W3TTT
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A friend has given me his qcx to try and repair.
With my limited knowledge I would like some suggestions where to look for the problem.
The Lcd lights segments appear to be flashing when qcx powered on.
He had shorted 12v to one of the encoder pins.
Voltages on the pins are low -88 +88.
I have? taken other voltage readings on the board and they are all low except for the 12v to the chips lines.
So I am thinking it is something in the 5v line that is smoked.
I also replaced the voltage regulator.
I have done a visual inspection and can see any part that are smoked.
The firmware has been replaced.
Any suggestions appreciated.
Norman
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One u3s cause tvi on 40,30 and 20m, tx into an inverted L 5m high around 25m long. Antenna wire runs within 1m of TV antenna.?
2nd u3s loaned out at a different location on 20 and 40 into a long wire but not near a TV antenna also causes tvi.
3rd us3s, also loaned out at another different location is to be tested.
I have a sdrplay duo sdr which covers up to 2GHz, I'll check tomorrow for harmonics and also tx into dummy loads.
--
The universe is made up of Protons, Neutrons, Electrons but contains only one M0RON.
|
Yeah...an SDR dongle and waterfall display image can say a lot. Particularly if your RX can goto 1 MHz. But all SDR dongles will cover the television broadcast spectrum.
On Sun, Apr 28, 2019, 9:03 AM Mike < mike@...> wrote: It would help if we knew what frequencys, aerials, distance from the offended
TV etc.
On 28 Apr 2019 at 5:19, M0RON wrote:
> Anyone else had their u3s cause interference to digital tv?
> I have 4 u3s, two of which cause TV interference, when they are actually
> transmitting the interference is quite bad, but even between transmissions
> blocking occurs.
> Satellite TV reception not affected not streaming, just terrestial digital
> tv.
> Andy
> --
> The universe is made up of Protons, Neutrons, Electrons but contains only one
> M0RON.
>
>
>
>
|
It would help if we knew what frequencys, aerials, distance from the offended
TV etc.
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On 28 Apr 2019 at 5:19, M0RON wrote: Anyone else had their u3s cause interference to digital tv?
I have 4 u3s, two of which cause TV interference, when they are actually
transmitting the interference is quite bad, but even between transmissions
blocking occurs.
Satellite TV reception not affected not streaming, just terrestial digital
tv.
Andy
--
The universe is made up of Protons, Neutrons, Electrons but contains only one
M0RON.
|
The QRP Labs oscillators generate a square wave? which may be
used with a BPF but the square wave will still be there radiating
odd harmonics up to UHF. Try changing the fundamental freq to see
if it changes.
On 28/04/2019 13:19, M0RON wrote:
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Anyone else had their u3s cause interference to digital tv?
I have 4 u3s, two of which cause TV interference, when they are
actually transmitting the interference is quite bad, but even
between transmissions blocking occurs.
Satellite TV reception not affected not streaming, just terrestial
digital tv.
Andy
--
The universe is made up of Protons, Neutrons, Electrons but
contains only one M0RON.
|
Anyone else had their u3s cause interference to digital tv?
I have 4 u3s, two of which cause TV interference, when they are actually transmitting the interference is quite bad, but even between transmissions blocking occurs.
Satellite TV reception not affected not streaming, just terrestial digital tv.
Andy
--
The universe is made up of Protons, Neutrons, Electrons but contains only one M0RON.
|
Re: I ordered a replacement QCX kit.
I used the Donegan Optivisors for many years in my medical practice and now have two at home in my shack. ?One is over 30 years old and still adjusts to different sized heads. ?I use the 2x and 4x mostly and have the MicroMark LED set on the 4 x along with the flip down extra magnification.... a must in seeing the ID info on chips. ?Couldn¡¯t live without them. ?Worth the extra money. ?All the ¡°eastern rim¡± sets I have seen at Dayton are flimsy and are of a plastic that will deteriorate in time. ?They just feel cheap. ?For something that you will use for the rest of your life get the original Donegan. David J. Wilcox K8WPE¡¯s iPad
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On Apr 27, 2019, at 8:34 PM, Mike Strelitzer < mstrelitzer@...> wrote: As a Toolmaker for 39 years, I swear by the Donegan Optivisor. I have accumulated 4 over the years. I have a #10 and #7 at home, and I added the Optiloupe to the #7 (duplicate setup at work). My first one I got as an apprentice in 1980. Couldn't live without them, lol.
Bought a knockoff once. Fell apart after a year. The real deal have never failed me On Sat, Apr 27, 2019, 7:23 PM jhowell39 via Groups.Io <jhowell39= [email protected]> wrote: When I was dabbling in guitar building, I tried a couple.? The biggest issue for me was that the right eye didn't focus at the same distance as the left and the? field of view was pretty concentrated.? After borrowing Optivisors, I purchased my own.
--
Jim, KJ7EZN? ? 73!
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James Daldry W4JED
M0RON
Joe Cotton
Mike
David Wilcox K8WPE