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Re: QCX 20m - Almost done... can't wait

 

Hi Keith,

There are about 30 SMD devices including two 8-lead ICs (not as close a lead pitch as the FST3253 as used in QRP Rx ).? R's and C's are 0805 , with four SMD can-type electrolytics.? The PCB board is quite large so components aren't packed too closely.? All components are clearly packed and labelled.

Obviously I don't know if you are happy with SMD construction but I feel it is fine even as a first SMD project.

Hope that helps.

Regards

Dave

G3WUN

'Test equipment is good'

On 06/12/2017 19:03, Keith VE7GDH wrote:
Dave G3WUN wrote...

I built the mWattmeter II (kit) from MultusSDR :



Just curious... are the the MultusSDR kits just the
circuit boards and parts... i.e. you get to solder all
of the SMD part on the circuit board? TIA


Re: QCX 20m - Almost done... can't wait

 

Dave G3WUN wrote...

I built the mWattmeter II (kit) from MultusSDR :



Just curious... are the the MultusSDR kits just the
circuit boards and parts... i.e. you get to solder all
of the SMD part on the circuit board? TIA

--
73 Keith VE7GDH


Re: QCX 30 Complete

 

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Thanks Martin, got a 17 and 20 mtr to box up, glad I have a good stash of beer!!
?
Cheers
72/3
?
Ian G4GIR


Re: QCX Manual

 

Most of the toroids are easy. The only challenging one is T1; it takes
a bit of work to get all the wires in the right holes.

On Wed, Dec 6, 2017 at 1:44 PM, Keith VE7GDH <ve7gdh@...> wrote:
Vernon VE1VDM wrote...

My kit should be here in a day or two so will be
printing it off soon...
I didn't print any of the manuals. I just opened them up
on a tablet (iPad) and used it while working on the QCX etc.
I'm about half way through the second one, but haven't wound
the toroids for the first one yet. Procrastination? Fear?
I'll decide tomorrow.

--
73 Keith VE7GDH



Re: FT8 for U3?

 

Great !? I've been hoping it would be added.? Will v3.13 be available soon?


From: Hans Summers <hans.summers@...>
To: [email protected]
Sent: Wednesday, December 6, 2017 9:52 AM
Subject: Re: [QRPLabs] FT8 for U3?

Hi Dean

I already coded FT8 in my U3, next version v3.13, last week. I have not yet had a chance to test it. v3.13 also contains JT4 and RTTY modes.?

73 Hans G0UPL

On Wed, Dec 6, 2017 at 4:48 PM, Dean Smith <g7eob1@...> wrote:
I think there are two answers to this one, but i'll ask all the same!
Any chance of FT8 mode being included in the U3 firmware.
I know the room in the ATMEGA is tight!? (PI mode anybody still use it???)
I understand this mode is a quick version of JT65 (15 second slots)!
The idea behind this is that it would be possible to fit in another tx mode within a frame.
I'm sure most will have 15 seconds spare, before calibration starts?!
thoughts anybody???
Dean G7EOB






Re: QCX Manual

 

Vernon VE1VDM wrote...

My kit should be here in a day or two so will be
printing it off soon...
I didn't print any of the manuals. I just opened them up
on a tablet (iPad) and used it while working on the QCX etc.
I'm about half way through the second one, but haven't wound
the toroids for the first one yet. Procrastination? Fear?
I'll decide tomorrow.

--
73 Keith VE7GDH


Re: FT8 for U3?

 

But how intrusive would an FT8 beacon be with such low power? Everytimne a new mode comes out,all rush to it while other modes are left for dead.
See JT9 activity or Opera...slowly going away.
I find JT65 horribly intrusive on 30m...these guys do not care where they are QSO`ing. Directly over WSPR in most cases.
RTTY even worse.
The shocking part is I hear JT65 with no antenna connected...how much power do you need?
I sometimes wonder if most users even acknowledge activity on the waterfall before transmitting?
WSJT-X at least prevents TX out of frequency...too much junk software spreading around out there in my opinion.
Jim


Re: QCX 30 Complete

 

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Very nice!

?

Martin

G0PJO

?

From: [email protected] [mailto:[email protected]] On Behalf Of IAN FRITH via Groups.Io
Sent: 06 December 2017 17:55
To: [email protected]
Subject: [QRPLabs] QCX 30 Complete

?

Hi all

?

Finished the complete build of QCX 30. Hopefully a pic will accompany this message.

?

The enclosure is an RS Pt No 411-6632 TS1 sloping front panel, 58 mm rear height and 35 mm front height.

Have added facilities to select the test options from the front panel and fitted a 3A variable voltage regulator to adjust the power output.

Also fitted the VU2ESE AGC design in series with C21. The AGC is a very useful addition.

?

I have a small milling machine to machine the enclosure and the engraving was carried out courtesey of my brother (cost me a few beers).

?

It’s working very well with best QRB VK3AXF @ 16897km.

?

Thanks Hans for your very generous help to get this one working!!

?

72/73

?

Ian G4GIR

?

?


Re: Winding Tip for 80 Mtr QCX transformer (T1)

 

Good idea John, I have a few trimmers in the junk box that will do the job and it might give an idea how much extra inductance is required so I can calculate the number of turns required Thanks Robin G4DNP


QCX 80 Transceiver - Connection for a Straight Key

 

After 30 years of no activity, I am still learning CW with a straight key which I shall continue to use for the time being.
I recently completed the building of the 80m of the QCX and it is functioning reasonably well except for a few tweaks such as?possibly adding a few turns to T1 transformer.
?
After completing the assembly, I connected 50R dummy load, headphones, and straight key (Kent) with mono jack and was ready for alignment.
When I powered up with a LiFe battery (9.5V) I was rewarded with a loud tone in headphones and after some agonising?time I established that the transmitter was in fact being keyed (measured power at RF BNC output with DVM)?even though I was not keying.

Removal of key jack stopped the keying and I was able to proceed with the alignment.

I also have a Palm Radio PPK straight key which has a stereo jack but this also caused the transmitter to turn on without keying and I removed this.

The microswitch keyed the transmitter normally as did shorting the two offboard connections at the front of the PCB.

My first thought was that there was a fault with the key stereo socket but on closer inspection of this and the circuit diagram it seem that the transmitter is keyed when the
either a mono jack or a "standard stereo jack" is inserted in the socket causing a connecting between the ground and either (or both of the contacts in the socket).

In fact partially inserting either jack into the socket did not key the transmitter until I started using the key. This is obviously unsatisfactory and I wonder whether there is a "suitable" jack which should be used (unfortunately, and embarrassingly so, I am not yet?up to speed with Iambic keys etc).
In fact, I have a short?extension lead with tip, 2 intermediate sections plus the bore which did not set off the transmitter when inserted.Apart from using the microswitch, obviously a quick fix would be to connect a suitable mono (?)?socket to the front 2 key pins?on the PCB?but this is?also not an ideal as the wires could easily break.

Have I made a basic mistake or is this to be expected ?

If it is to be expected, then I believe a caution is required in the assembly manual stating that "..mono jacks (and simple stereo jacks??)?cannot be used in the key socket or should be of a specific length otherwise the transmitter will be keyed".

This would be extremely useful for the inexperienced operator to make it "idiot proof".

I have had a lot of pleasure building this kit so please allow this old man a little indulgence as I can't wait to order the 17m version (I have a MTR-3B for 20/30/40m).

Comments are invited.
Best 73s

Robin
G4DNP








QCX 30 Complete

 

开云体育

Hi all
?
Finished the complete build of QCX 30. Hopefully a pic will accompany this message.
?
The enclosure is an RS Pt No 411-6632 TS1 sloping front panel, 58 mm rear height and 35 mm front height.
Have added facilities to select the test options from the front panel and fitted a 3A variable voltage regulator to adjust the power output.
Also fitted the VU2ESE AGC design in series with C21. The AGC is a very useful addition.
?
I have a small milling machine to machine the enclosure and the engraving was carried out courtesey of my brother (cost me a few beers).
?
It’s working very well with best QRB VK3AXF @ 16897km.
?
Thanks Hans for your very generous help to get this one working!!
?
72/73
?
Ian G4GIR
?
?


Re: QCX Manual

 

No changes planned, Vernon

73 Hans G0UPL?
?

On Dec 6, 2017 20:52, "Vernon Matheson" <vmath@...> wrote:
?Hi Hans,
?
Just wondering if there are any changes coming to the QCX assembly and operating manual version 1.08 in the next short while. My kit should be here in a day or two so will be printing it off soon.
?
Thanks
?
Vernon
?


Re: QCX 20m - Almost done... can't wait

 

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Hi Kurt,

I built the mWattmeter II (kit) from MultusSDR :

I found it does all I need for QRP operation and was quite accurate when compared to my other test kit .? Now recently superceded by a new version,

73

Dave

G3WUN


On 06/12/2017 17:29, Kurt Zimmerman wrote:

Greetings all again;
? ? I would like to add the following on my build.? When it comes to test equipment my resources are quite limited.? I don't even have a QRP Watt/SWR meter.??

? Since I'm using an 80m doublet antenna what I'll do is adjust my tuner with my primary radio (Yaesu FT 920) to set the tuner correctly.? Then I'll take the antenna connection and move it over to the QCX operating on or about the frequency I tuned up for.??

? ? I do have a QRP antenna tuner but only plan on using it in the field.

If anyone could suggest a good reliable Watt/SWR meter that will not break the bank I'm all ears..

Other than that I wrapped my toroids I wound them in accordance to Han's directions.??

I am now curious to see how well a stock built QCX-20 is going to play.

72;
Kurt - W2MW
-------- Original Message --------
Subject: [QRPLabs] QCX 20m - Almost done... can't wait
From: "Kurt Zimmerman" <kurt@...>
Date: Wed, December 06, 2017 10:04 am
To: [email protected]

Greetings all;
? ? Well I completed my QCX 20m last evening.? I have had my share of boneheaded mishaps which I take full credit for.? Initially when I was installing the glass diodes I broke one.? I manage to pillage one from a failed QRP project.? Last night when I was installing the volume pot I applied a bit too much pressure on it and cracked the board in the pot.? Net result I have no volume out.? I was able to jumper the leads on the pot to discover I am getting plenty of audio.? I hope to salvage the pot and to get the rig on-line this evening.? I may have to wait until the weekend do get to operate during the day when 20m will do better with propagation.


Hopefully these pictures come through.??

Just want to thank Hans for the continue support as well as providing just a great product.? Other than my missteps it was a great build.? Can't wait to get on the air.

72/73;
Kurt - W2MW



QCX Manual

Vernon Matheson
 

?Hi Hans,
?
Just wondering if there are any changes coming to the QCX assembly and operating manual version 1.08 in the next short while. My kit should be here in a day or two so will be printing it off soon.
?
Thanks
?
Vernon
?


Re: Winding Tip for 80 Mtr QCX transformer (T1)

 

Good comment John. I'm suprised it has'nt been made before - or has it.

On 6 Dec 2017 at 17:36, John Pagett wrote:

Robin,
At this stage, rather than add turns, why not add some extra capacitance
across the trimmer? I would imagine the L/C ratio isn't critical in this
instance. As a start, I'd try something a little less than the range of the
trimmer itself. I don't have the information to hand but if the trimmer is
say 5 to 40pF then something around 30pF can't be too much.
Just tack the cappy on the back of the board at this stage.
Of course you might need more capacitance still, but it's an easy experiment
to make.?
Regards,?
John
G4YTJ


Sent from my mobile phone

-------- Original message --------
From: robin.travis@...
Date:
To: [email protected]
Subject: [QRPLabs] Winding Tip for 80 Mtr QCX transformer (T1)

Hi Des (again) and others
I just searched this topic and your name came up again.
I had to have 3 attempts to wind the T1 transformer.

On the first attempt, I ran out of 28swg wire to complete the winding having
obviously?used generous amounts for the other inductances.
(QRP Labs - please note that a little more wire would not go amiss).
I had some 27swg and 30swg wire and decided to try the 27swg?but trying to
wind 83 turns on a T50-2 toroid is no easy task and I abandoned this in
favour of the 30swg.

I managed to wind the transformer with quite a bit of overlap of 30swg wire
and I presume I have wired it up correctly as I am now hearing stations?
reasonably well from continental Europe. Obviously, 30swg wire?is quite
delicate but it?is certainly workable if one is careful.

The issue I have is with the alignment: it is starting to peak but I am only
achieving a scaling factor of 5 with the plates of C1 completely closed and I
now have to add some more turns.
For optimum performance,?is the target value around 9 as indicated in the
manual and I am wondering whether it is easier to remove turns rather than
add.
In other words, would it be better to add 10 turns rather than 5 turns as
suggested in the manual ?

Again input from you or any other would be most welcome.

73s

Robin
G4DNP


Re: Winding Tip for 80 Mtr QCX transformer (T1)

 

开云体育

Robin,
At this stage, rather than add turns, why not add some extra capacitance across the trimmer? I would imagine the L/C ratio isn't critical in this instance. As a start, I'd try something a little less than the range of the trimmer itself. I don't have the information to hand but if the trimmer is say 5 to 40pF then something around 30pF can't be too much.
Just tack the cappy on the back of the board at this stage.
Of course you might need more capacitance still, but it's an easy experiment to make.?
Regards,?
John
G4YTJ


Sent from my mobile phone


-------- Original message --------
From: robin.travis@...
Date:
To: [email protected]
Subject: [QRPLabs] Winding Tip for 80 Mtr QCX transformer (T1)


Hi Des (again) and others
I just searched this topic and your name came up again.
I had to have 3 attempts to wind the T1 transformer.

On the first attempt, I ran out of 28swg wire to complete the winding having obviously?used generous amounts for the other inductances.
(QRP Labs - please note that a little more wire would not go amiss).
I had some 27swg and 30swg wire and decided to try the 27swg?but trying to wind 83 turns on a T50-2 toroid is no easy task and I abandoned this in favour of the 30swg.

I managed to wind the transformer with quite a bit of overlap of 30swg wire and I presume I have wired it up correctly as I am now hearing stations? reasonably well from continental Europe. Obviously, 30swg wire?is quite delicate but it?is certainly workable if one is careful.

The issue I have is with the alignment: it is starting to peak but I am only achieving a scaling factor of 5 with the plates of C1 completely closed and I now have to add some more turns.
For optimum performance,?is the target value around 9 as indicated in the manual and I am wondering whether it is easier to remove turns rather than add.
In other words, would it be better to add 10 turns rather than 5 turns as suggested in the manual ?

Again input from you or any other would be most welcome.

73s

Robin
G4DNP


Re: QCX 20m - Almost done... can't wait

 

Greetings all again;
? ? I would like to add the following on my build.? When it comes to test equipment my resources are quite limited.? I don't even have a QRP Watt/SWR meter.??

? Since I'm using an 80m doublet antenna what I'll do is adjust my tuner with my primary radio (Yaesu FT 920) to set the tuner correctly.? Then I'll take the antenna connection and move it over to the QCX operating on or about the frequency I tuned up for.??

? ? I do have a QRP antenna tuner but only plan on using it in the field.

If anyone could suggest a good reliable Watt/SWR meter that will not break the bank I'm all ears..

Other than that I wrapped my toroids I wound them in accordance to Han's directions.??

I am now curious to see how well a stock built QCX-20 is going to play.

72;
Kurt - W2MW

-------- Original Message --------
Subject: [QRPLabs] QCX 20m - Almost done... can't wait
From: "Kurt Zimmerman" <kurt@...>
Date: Wed, December 06, 2017 10:04 am
To: [email protected]

Greetings all;
? ? Well I completed my QCX 20m last evening.? I have had my share of boneheaded mishaps which I take full credit for.? Initially when I was installing the glass diodes I broke one.? I manage to pillage one from a failed QRP project.? Last night when I was installing the volume pot I applied a bit too much pressure on it and cracked the board in the pot.? Net result I have no volume out.? I was able to jumper the leads on the pot to discover I am getting plenty of audio.? I hope to salvage the pot and to get the rig on-line this evening.? I may have to wait until the weekend do get to operate during the day when 20m will do better with propagation.


Hopefully these pictures come through.??

Just want to thank Hans for the continue support as well as providing just a great product.? Other than my missteps it was a great build.? Can't wait to get on the air.

72/73;
Kurt - W2MW


Re: Low Power fix on QCX 80 and a sugestion for a possible addition to QCX test gear to measure inductance.

 

Hi Alan

Current consumption charts that I measured are in the manual.

Agreed, only the final measurement means anything, and only into a 50-ohm dummy load. The onboard power measurement is not claimed to be particularly accurate either.?

73 Hans G0UPL?
?

On Dec 6, 2017 8:19 PM, "Alan G4ZFQ" <alan4alan@...> wrote:

In my opinion, I also have a slightly lower power output?than expected.
Using the online power meter, I ?have 5.2 watts on the drains of Q1, Q2 and Q3 (with both 9.5 and 11.3 V power source) and the following measurement across L1:
L1/L2 Junction = 3.3 watts (11.3V)? and?2.3 watts (9.5V)
L1/power output BNC socket = 2.0 watts (11.3V) and 1.5 watts (9.5V)

I understand these power measurements are not necessarily accurate values but serve for the purpose of comparison.


Robin,

The only one that has any chance of giving some sort of accurate indication is the final one.
The others are not into 50 ohms so really mean nothing.


I note the possible removal of turns from the inductances L1, L2, L3 and L4 but before embarking on this I would be interested to know which inductance did you find was the most critical and turns removed.

I think each has a small effect and all may require adjustment to make a significant difference.
Something somebody said off-list makes me wonder what current does the CQX take, RX and TX? Although perhaps that may mean nothing.

73 Alan G4ZFQ





Re: Low Power fix on QCX 80 and a sugestion for a possible addition to QCX test gear to measure inductance.

 

In my opinion, I also have a slightly lower power output?than expected.
Using the online power meter, I ?have 5.2 watts on the drains of Q1, Q2 and Q3 (with both 9.5 and 11.3 V power source) and the following measurement across L1:
L1/L2 Junction = 3.3 watts (11.3V)? and?2.3 watts (9.5V)
L1/power output BNC socket = 2.0 watts (11.3V) and 1.5 watts (9.5V)
I understand these power measurements are not necessarily accurate values but serve for the purpose of comparison.
Robin,

The only one that has any chance of giving some sort of accurate indication is the final one.
The others are not into 50 ohms so really mean nothing.

I note the possible removal of turns from the inductances L1, L2, L3 and L4 but before embarking on this I would be interested to know which inductance did you find was the most critical and turns removed.
I think each has a small effect and all may require adjustment to make a significant difference.
Something somebody said off-list makes me wonder what current does the CQX take, RX and TX? Although perhaps that may mean nothing.

73 Alan G4ZFQ


Re: FT8 for U3?

David Bowman
 

Hmmm.

That's a tricky one.? I wonder if transmitting a beacon using a mode designed for 'rapid' QSOs is something we should even consider doing?

Thanks

David? G0MRF