Re: QRP rags to riches
#qcx
I got the internal keyer issue
resolved.?
Oddly enough, it seems the problem was
RF feedback related to running into a dummy load that was setting
too close to the rig.? Later, when I put the rig on my dipole the
problem went away.? The long cord on my key probably didn't help.
The QCX 40 seems to be working great
this AM, heard? Chinese and Marianas Is. DX.
Power out is abt 3W on 13.8V, probably
try 16V later but want to make some heat sinking upgrades first.?
I rough calibrated it by zeroing my SDR
on WWV and then calibrated the QCX against the SDR on 40.? It's
close enough to find spots where they should be.?
The radio seems to be working fine but
the R24 and R17 adjustments did not go right.?? Both adjustments
are at minimum with the pots full CCW.? I can't "hear" any trace
of the other side band by ear, but I'd feel better abt the
situation if I could get a null.
There was a recent thread related to
that issue I'll review. ? Also could be my selections of R's
trying hit a 500 Hz CF,? might re-do those for 600 hz and see if
that flys straighter.
73 Jack KZ5A
On 4/13/2019 12:39 AM, Dave N3AC wrote:
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Try the Logitech again, with a mono plug.?
On Sat, Apr 13, 2019, 00:39
Jack Brabham - KZ5A < kz5a@...> wrote:
I just
turned it off, set it for straight key, and started using
my usual shack keyer Logikey K1.
The
internal keyer is not usable, impossible to send coherent
code.?? Not even close to being usable.
I noticed
one of the QRP kit sites has a board to "fix" QCX keying
and apparently I need one.
Same key
works fine in my K1.
73 Jack
KZ5A
On
4/12/2019 7:26 PM, Chopper wrote:
The key input is designed for a
straight key or a paddle depending on what is selected in
menu.? It does not work well with most keyers. If using a?
paddle mode B seems to work best.
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Re: Fried U3s on 12volts. Hopeless?
#u3s
the frequency offset is set wrong. With this GPS connected, it gets pushed up too high. Maybe this is to do with the 1pps signal? Chris, How far off is it? Does it stabilise?I'd think just about any PPS would work fairly well, it gets smoothed. I'm not sure about how pulse width and polarity will affect it. You have read the operating manual? 73 Alan G4ZFQ
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Have a look at " The scientist and Engineer's guide to Digital
Signal Processing " by Steven W Smith. Quote from the Book, " this
book is written for those who want to use DSP as a tool, not a new
career". Lots of examples and not lots of maths and equations.
On 13/04/2019 09:29, Richard Harris via
Groups.Io wrote:
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John,
One useful resource for phasing-type rigs is the (free)
Quadnet filter design program from Tonne Software.? This
program calculates the component values for various orders of
all pass filters (using op-amps) that approximate to wide band
90 deg phase shift networks.? The software calculates the
maximum opposite sideband suppression with these networks,
although to achieve that requires very careful construction
and setting up.?
Richard G3OTK
On Saturday, 13 April 2019, 02:21:58 BST, John VA7JBE
via Groups.Io <va7jbe@...> wrote:
Hi Alison,
I read about this a while back and have been looking
for some more information on 3rd order all pass
filters since then.? Unfortunately whatever I can find
is a bit over my head.? Could you recommend any
resources that might be a bit more accessible to the
self-taught amateur?? I'm about to have some free time
on my plate and I'd be interested in learning more
about this.
Cheers,
John VA7JBE
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Re: Fried U3s on 12volts. Hopeless?
#u3s
Hello,
I just connected the wires and it burst into life.
However, I did end up logging in?to the GPS using the free software to switch some things off that we're not needed. I also?set it to UTC instead of GPS time.
But I do have one issue, the frequency offset is set wrong. With this GPS connected, it gets pushed up too high. Maybe this is to do with the 1pps signal? But I wouldn't have thought?that the 1PPS could be wrong? I'm still trying to get to the bottom of this issue. I don't know if anybody else has had this issue? I've searched the forum but did not find anything.
--
Best regards,
Chris
M0XFL
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John,
One useful resource for phasing-type rigs is the (free) Quadnet filter design program from Tonne Software.? This program calculates the component values for various orders of all pass filters (using op-amps) that approximate to wide band 90 deg phase shift networks.? The software calculates the maximum opposite sideband suppression with these networks, although to achieve that requires very careful construction and setting up.?
Richard G3OTK
On Saturday, 13 April 2019, 02:21:58 BST, John VA7JBE via Groups.Io <va7jbe@...> wrote:
Hi Alison,
I read about this a while back and have been looking for some more information on 3rd order all pass filters since then.? Unfortunately whatever I can find is a bit over my head.? Could you recommend any resources that might be a bit more accessible to the self-taught amateur?? I'm about to have some free time on my plate and I'd be interested in learning more about this.
Cheers,
John VA7JBE
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Re: QRP rags to riches
#qcx
Try the Logitech again, with a mono plug.?
On Sat, Apr 13, 2019, 00:39 Jack Brabham - KZ5A < kz5a@...> wrote:
I just turned it off, set it for
straight key, and started using my usual shack keyer Logikey K1.
The internal keyer is not usable,
impossible to send coherent code.?? Not even close to being
usable.
I noticed one of the QRP kit sites has
a board to "fix" QCX keying and apparently I need one.
Same key works fine in my K1.
73 Jack KZ5A
On 4/12/2019 7:26 PM, Chopper wrote:
The key input is designed for a straight key or a paddle depending
on what is selected in menu.? It does not work well with most
keyers. If using a? paddle mode B seems to work best.
|
Re: QRP rags to riches
#qcx
I just turned it off, set it for
straight key, and started using my usual shack keyer Logikey K1.
The internal keyer is not usable,
impossible to send coherent code.?? Not even close to being
usable.
I noticed one of the QRP kit sites has
a board to "fix" QCX keying and apparently I need one.
Same key works fine in my K1.
73 Jack KZ5A
On 4/12/2019 7:26 PM, Chopper wrote:
toggle quoted message
Show quoted text
The key input is designed for a straight key or a paddle depending
on what is selected in menu.? It does not work well with most
keyers. If using a? paddle mode B seems to work best.
|
Re: QRP rags to riches
#qcx
The key input is designed for a straight key or a paddle depending on what is selected in menu.? It does not work well with most keyers. If using a? paddle mode B seems to work best.
|
Hi Alison,
I read about this a while back and have been looking for some more information on 3rd order all pass filters since then.? Unfortunately whatever I can find is a bit over my head.? Could you recommend any resources that might be a bit more accessible to the self-taught amateur?? I'm about to have some free time on my plate and I'd be interested in learning more about this.
Cheers,
John VA7JBE
|
Re: QRP rags to riches
#qcx
Parts came in today, hoooray.?? I put the new uP in my DOA QCX 40 and it came up running.? Got thru the alignment, sort of OK but haven't got a distinct null on phase Lo.? R24, ends with up a minimum at full CCW.?? PO is abt 3 watts on 13.9V.?
I re-filtered it for ~600Hz and there may be some config parameter I missed.?? Anyway I'm listening to W1AW, sounds great.??
Couldn't use the keyer, almost impossible to make a correct character, so I put it in St Key mode and plugged in my trusty LogiKey K1 which works great.? No idea what the deal with the keyer is but I'll look into it later.
Also got my "practice Arduino" today and got stated on Jack P's book, got "blink" to work.WooHooo.
73 Jack KZ5A
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I had a persistent qcx20 bug that turned out to be cold joint on upper component side layer found only by careful exam of upper board? joints. Just a suggestion.
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Yeah, that was the first thing I checked - I soldered T1 before any other parts, and I made sure to test continuity from the pads.
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Check your solder connections on T1.? Measure from solder/pad and not the wire end.? A poor solder connection can cause BPF peaking issues.
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Yes, band is set for 20m.? I've "factory reset" a couple times, and always set it back to 20m.
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The other Q I have:? since I can't get Peak BPF over 5 turning the pot, should I add or remove turns from the larger secondary on T1?
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3.9 Band set for 20m ?
72? / 73,
Bill, N4QA
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Hm.? I checked the pot, and it looks fine - but for good measure, I reflowed all three connections.? Didn't fix the problem.
However, I've discovered that when I key down, the clicking goes away, and I hear a tone.? On key up, the clicking is back.
It doesn't go away when I switch to Peak BPF - but its character does change, and in Peak BPF turning the cap does affect the sound a bit.
Curious.
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Nope, S-meter is not enabled - this literally starts as soon as it's powered on, even after a factory reset.
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Yup... re-solder your volume pot. ;-)
73,
Stephen VE6SVJ Sent from an electronic device.
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On Apr 12, 2019, at 11:34, riz-qcx@... wrote: I just got my QCX-20 assembled and i'm having an issue I haven't seen talked about (though I could just be blind) - without plugging in headphones, I started trying to align the BPF, and couldn't get a peak (it always stayed around 4-5).? ?I looked over all the parts and solder joints and such and everything looks good.? So, I plugged in headphones to hear this loud tone when aligning - but I actually get a loud clicking as soon as the unit is powered on, which leads me to believe the problem might be elsewhere?? The sound seems to vibrate at a few Hz, and the volume is definitely affected by the volume control.? ?Plugged into my bench supply, it draws 140mA at 13.8V, and the display and menus work fine.
I'm still investigating (I have a DMM and oscilloscope, and I'm normally very good at assembly), but does this sound familiar to anyone???
Thanks!
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Did you enable the S meter? ?On my 20m QCX it makes a sort of clicking sound with the S meter enabled. ?Disabling the S meter completely removes that clicking sound.
Curt M.
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N3MNT
Stephen VE6SVJ