Re: QDX: Section 2.16 ¡°replace 47uH inductors¡±
It's possible that some coupling is happening even with the cracked chip cap but it's not going to be anywhere near its designed value.?
On Mon, Nov 15, 2021, 12:04 PM Julian N4JO < n4jo@...> wrote: To augment Fred's comment: C2 is absolutely necessary: it's inline with the antenna, so without it the QDX is completely dumb and deaf. I'm not sure how you're getting any signal; maybe it isn't completely destroyed?
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Julian, N4JO.
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Re: QDX - No RF output, Tx line stays low
N3MNT,
I assume that you changed the QDX USB Audio to not be the default audio output device in Windows and that you went into the sound volume mixer and made sure that the QDX output was full.? I am not at my Windows PC that has the QDX connected so cannot show a screenshot.? You can get to the sound mixer by right-clicking the speaker symbol in the lower right corner of the display.
73
Evan
AC9TU
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Re: QDX: Section 2.16 ¡°replace 47uH inductors¡±
To augment Fred's comment: C2 is absolutely necessary: it's inline with the antenna, so without it the QDX is completely dumb and deaf. I'm not sure how you're getting any signal; maybe it isn't completely destroyed?
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Julian, N4JO.
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Re: QDX: Section 2.16 ¡°replace 47uH inductors¡±
It's toast.? Replace it.? If you can fit a leaded component in there... That will work too.
Fred W0FMS?
Folks at home,
I built the QDX kit over the weekend. Enjoyed every moment of this build.?
The error occurred when I got to section 2.16. I was fitting the wired axial inductor in place as per the instructions, when I crushed, or cracked the C2 component. (I was still able to solder the wire to the bottom of C2) Should I replace the item, or will it not affect the device??
The QDX connects to my Windows 10 pc with no issues. I can see received signals on the FT8 & JS8 waterfall. I have not ?transmitted yet.
If i need to replace C2, could one of you link me to where I can order this piece?
Best,
Jason K7JWN?
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Hi Ted. Yes I have done this. Since you are going down to 40 meters, don't forget to also add the 39 pF (390) capacitor in position C5. It won't have one there for the 20 meter version. You got one in your kit if you still have it around. And yes you have to rewind all the toroids ihcluding L4 and change C30 from 30 pF to 56 pF. The normal BPF and LPF adjustment procedures should get you right back up and going .... Good luck ... Ron
On Mon, Nov 15, 2021 at 8:04 AM Ted 2E0THH < qrp@...> wrote: After a year on 20m,? I have decided to convert my Mini up to 40m.?
This looks very straight forward as the toroid cores are the same, just a question of rewinding them all appropriately.
On the caps, I think I might just just snip and break the ones that need to be replaced, then solder the new caps onto the old legs. The hope is this will save the PCB pads and this would also allow a much easier band change in the future, if I ever go there.
I briefly considered using PCB pins for both the caps and toroids, but it is probably now both perilous to the PCB and complete overkill. I might have considered it on the initial build.?
Has anyone else converted bands on their QCX?
73s Ted
2E0THH
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Re: QDX - No RF output, Tx line stays low
Some additional testing this afternoon.? It appears that the issue of not keying the TX when using windows is dependent on the machine.? I am unable to key the QDX except on 40M on one laptop? but able to key it on all bands on an older windows tablet running Win 10.? Will try Raspberry Pi4 later on.
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QDX: Section 2.16 ¡°replace 47uH inductors¡±
Folks at home,
I built the QDX kit over the weekend. Enjoyed every moment of this build.?
The error occurred when I got to section 2.16. I was fitting the wired axial inductor in place as per the instructions, when I crushed, or cracked the C2 component. (I was still able to solder the wire to the bottom of C2) Should I replace the item, or will it not affect the device??
The QDX connects to my Windows 10 pc with no issues. I can see received signals on the FT8 & JS8 waterfall. I have not ?transmitted yet.
If i need to replace C2, could one of you link me to where I can order this piece?
Best,
Jason K7JWN?
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Hi Alan,
Indeed it could be either but only Hans can say how the design is supposed to be. Anyway, my filing worked so I am happy.
73, Gregg W7GRM
On Mon, Nov 15, 2021 at 10:19 AM Alan G4ZFQ < alan4alan@...> wrote: > I previously thought the fit problem was an offset on the PC board
> sides,
Gregg,
It is certainly offset on mine.
IC7 is almost flush with the edge of the board. Plenty of clearance for IC6.
The break-off cuts are not precisely aligned.
I do not think it is designed for the IC to fit into the slot? If so
then the other end of the board will be loose.
73 Alan G4ZFQ
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I previously thought the fit problem was an offset on the PC board sides, Gregg, It is certainly offset on mine. IC7 is almost flush with the edge of the board. Plenty of clearance for IC6. The break-off cuts are not precisely aligned. I do not think it is designed for the IC to fit into the slot? If so then the other end of the board will be loose. 73 Alan G4ZFQ
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Re: QDX - No RF output, Tx line stays low
On 15/11/2021 15:12, N3MNT wrote: it appears that the computer audio is just under the level needed to key the Tx I was surprised to find that mine was only just adequate. Dropping the WSJT-X slider down just 2dB resulted in no TX. 73 Alan G4ZFQ
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QDX: Much less frequent with 1.01b but still occurring periodically
Was monitoring JS8 for an hour or so, rx only. Then this occurred:
so I clicked on the TUNE button to go into transmit briefly, then toggled it back to receive and all was well. Vertical lines are gone and valid signals are being received. This happened far more often with 1.01a but still happens periodically with 1.01b.
W10
12V (3:2)
1.01b
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John AE5X
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Converting bands is, practically speaking, no different to replacing faulty components. You've already addressed the concerns, and suggested perfectly valid mitigation strategies. Go ahead as proposed :-)
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Julian, N4JO.
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Re: QDX - No RF output, Tx line stays low
Did some expanded testing this morning and see the following.? Windows 10 laptop WJST-X 2.5? Firmware 1.0c
Rig works perfect on 40M .? Audio set at 100% in control panel and volume slider.? Running 9V supply 117mA rcv. 950mA on tx ? and several over 1000mi contacts.
Rig changes freq and rcv works well however it appears that the computer audio is just under the level needed to key the Tx at other freqs.? Verified this also via the level meter in control panel under sound and 2 flashes on LED.?
I am going to try changing? the required level in the config menu to correct this and will report back.?
Also plan to experiment with slightly larger washer on output 170's as the board side tests cooler than the washer side.? 170s show about 90F with normal use ( top of case off).
Also noticed a few random CAT disconnections but a simple retry reconnects and operates correctly.?
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After a year on 20m,? I have decided to convert my Mini up to 40m.?
This looks very straight forward as the toroid cores are the same, just a question of rewinding them all appropriately.
On the caps, I think I might just just snip and break the ones that need to be replaced, then solder the new caps onto the old legs. The hope is this will save the PCB pads and this would also allow a much easier band change in the future, if I ever go there.
I briefly considered using PCB pins for both the caps and toroids, but it is probably now both perilous to the PCB and complete overkill. I might have considered it on the initial build.?
Has anyone else converted bands on their QCX?
73s Ted
2E0THH
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Hi Hans,
I previously thought the fit problem was an offset on the PC board sides, but now I am thinking the slot in the case is just a touch too narrow to allow the ICs to slide inside the slot like they should. Well, you can compare the pictures in the forum to what you have at QRP-Labs Towers. My current thinking: just some tolerance variation in the case which is easily fixed with a small file as I did.
Cheers, Gregg
These changes sound great Hans. Does the new PCB version address the edge of board IC6/7 case fitting issues that some have had?
No, it does not. I had never seen that issue here and I did the board Rev 2 before it was mentioned on the forum.?
73 Hans G0UPL
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These changes sound great Hans. Does the new PCB version address the edge of board IC6/7 case fitting issues that some have had?
No, it does not. I had never seen that issue here and I did the board Rev 2 before it was mentioned on the forum.?
73 Hans G0UPL
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Re: Info power 5 v qlg1 external
Thanks Julian, I'll have to check both power supplies. I'll do a new test tomorrow morning.? Thank you.? 73 de iu8eun Joseph
Il lun 15 nov 2021, 15:31 iu8eun Giuseppe Coppoletta < iw8rsb@...> ha scritto: Thanks Al, I leave the qlg1 connected as it should.? for the moment I have 2 U3S beacons in 20 and 17 meters with different powers.? Al, Thank you so much for your help.? have a nice day.? 73 de IU8EUN Joseph
OK, thank you. If all the LEDs work on the QLG1 showing power, data and PPS with the external 5V supply then the unit should communicate with the QCX-mini properly.
If it does not, then I'd look into verifying the connection between the two units.
Good luck & 73,
--Al
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Re: Info power 5 v qlg1 external
Thanks Al, I leave the qlg1 connected as it should.? for the moment I have 2 U3S beacons in 20 and 17 meters with different powers.? Al, Thank you so much for your help.? have a nice day.? 73 de IU8EUN Joseph
OK, thank you. If all the LEDs work on the QLG1 showing power, data and PPS with the external 5V supply then the unit should communicate with the QCX-mini properly.
If it does not, then I'd look into verifying the connection between the two units.
Good luck & 73,
--Al
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Re: Info power 5 v qlg1 external
Make sure you have the grounds connected properly. This means that at least one of the power supplies must be isolated from ground, itself, but referenced to ground at the QCX, or you may get a ground loop.?
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Julian, N4JO.
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Re: Info power 5 v qlg1 external
OK, thank you. If all the LEDs work on the QLG1 showing power, data and PPS with the external 5V supply then the unit should communicate with the QCX-mini properly.
If it does not, then I'd look into verifying the connection between the two units.
Good luck & 73,
--Al
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Fred Spinner
Julian N4JO
Ronald Taylor
N3MNT
Jason K7JWN
Ted 2E0THH