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Re: BNC connector position on the QCX mini

 

Here are two pictures of what it should look lie: side?view and end?view.
The side view shows that the connector must be parallel to the board, not angled up or down (this picture shows it angled slightly down, which is technically wrong), and the side view shows the flat on the underside of the flange. You may need to file it slightly to allow the connector to sit parallel.

Also, I solder the front two retaining lugs first, so that I don't add stress to the electrical connections by soldering them first, then pulling the connector around to orient it correctly.
Hope that helps.
--
Julian, N4JO.


Re: BNC connector position on the QCX mini

 

Excellent question. Your picture does look like if you obey that instruction then the connector will be tilted upwards, and that's definitely not a good thing.
I'll go and look at one right now, maybe take a picture, and respond within a few minutes... b.r.b...
--
Julian, N4JO.


BNC connector position on the QCX mini

Victor Nagoryanskii
 

Hey folks,
I'm a bit confused about instructions for the BNC connector installation on the QCX mini. Particularly about "The rim on the connector body should not overlap the edge of the PCB."
Please check a picture, something tells me that it doesn't look OK :) Shouldn't have I put it a bit to the right?

Cheers,
Victor, PA8MM


Re: QCX off Frequency

 

Hi Bill,

I thought the 12 Mhz is for the 160 m QCX only. Anyhow I will experiment with the 27 Mhz to see if I can get a closer match.

Martin
DK3UW


Re: QDX - No RF output, Tx line stays low

 

Update on the debug. First replaced C37 with .1uf. Inserted a 560 ohm resistor in series with L14. Measured the final¡¯s gates with a scope. Q8,10 had squashed signal,?Q9, 11 had 5 v square wave. The drain of these also looked ok with a sawtooth wave. Q8,10 drain looked bad. Removed Q8,10 remeasured and now tx signal never goes high. Loaded latest firmware and I¡¯m getting the 3 quick flashes but no tx signal. Will likely replace IC5 but I need to think about how to remove while the replacement?part is in transit.?

Jay




On Saturday, November 13, 2021, 5:19 AM, Steve via groups.io <qed28@...> wrote:

Hi Jay, did you mean to say R27 and not R37?? If it is R27 you are referring to, that's part of a filter/amplifier circuit for the I/Q signals.? That resistor should only affect receiver performance.? Steve KY4GX.

Glory to God in the highest, and on earth peace, good will toward men. Luke 2:14

--
Jginaz


Re: ceramic disc caps? #20m #40m

 

Julian
You are absolutely correct about a resonant circuit increasing the output amplitude. But how much does it affect the output square wave from the 3 PAs? Right now I went back and reassembled all the coils, L1 - L4, to there exact posted values and reinstalled them. Now instead of 0.5W I'm at 1.1W when I spread all the coil turns, so I may be on the correct track. At the drains of the 3 PAs ( actually at C29) I do get 29Vpp square wave.? I wonder if anyone can tell me if that is high enough to get 5W after going through the LPF??? Calculating power from Vpp is only good for a sine wave.? If this voltage in too low then I would go and look at the key shaping circuit.
syd/wtiv


Re: ceramic disc caps? #20m #40m

 

Ian
On second thought, don't see how that will give me any more information than an ohm meter measuring continuity from C29 to the bnc RF output connector which I have already done and found it to be OK! Taking the output this way will only show the waveform at the output of the 3 PAs, which I have already measured the Vpp with a scope which I found to be 28 Vpp.
syd/wt1v


Re: ceramic disc caps? #20m #40m

 

That is a very nice idea!!!? I will definitely give it a try! I guess the obvious is so easy to see that you can't see it.
Syd/wt1v


Re: QDX Isues with sWindows10 #qdx

 

Gregg,

Thank you again for the tips.

I do not know what changed other than I reset the QDX 3 times, ran on battery power,? and was able to receive and decode signals on all bands.? I had tried on battery before, but the Raspberry Pi was on the shack 13.8 volt supply.? I did leave the PC and QDX running for the last couple of hours and the QDX is still decoding.? I also made two contacts using it.

Again, no explanation other than now it seems to work.? We will see how long it continues to work.

73
Evan
AC9TU


Re: QDX shipping update

 


Hi Mike,
This is the type of magnifier I use although I didn't buy it off Amazon.

https://www.amazon.co.uk/Headband-Magnifier-Magnifying-Jeweler-Lights/dp/B08THRR7X1/ref=sr_1_7?keywords=head+magnifier+with+light&qid=1636831418&sr=8-7

Hans is seen using one in his video on tuning the LPF on a QCX. They are really good, although take a little bit of getting used to at first. There is a swing down high power lens on the right side which is very handy and saves using a loupe lens.

I have a "3rd hand" device with a couple of crocodile clips and a magnifying glass attached. They are O.K for some jobs but are nowhere near as good as the ones I have put the link to. They are available on Ebay and various other places and I reckon it is one of the best things I have bought in a long while....? apart from the QCX+ kit I am currently putting together. I have two QCX and now two QCX+ (including the one being worked on) the first three were built using a jewellers loupe at 20* magnification. This time the "Head magnifier" makes everything a lot easier.

Reg????? G4NFR


Re: JS8 QSO Party this weekend

 

Al,
If I see you on, I'll respond. You are a good stretch from my QTH so 20m would be the best chance. 40m seems weak here right now. I have only listened to JS8 so far so there is a good chance I would screw up my first transmission attempt anyway, ha, ha!

73,
Gregg W7GRM

On Sat, Nov 13, 2021 at 11:59 AM Al Holt <grovekid2@...> wrote:
Gregg,
Looks like a good variety! I'll add @QRP and @QRPLABS to mine. Don't have the QDX yet, but I do have 4 QCX's and a couple of U3S.'
I'm going to try using the RS-HFIQ rig I have that pushes 4W today on JS8Call.

--Al
WD4AH


Re: JS8 QSO Party this weekend

 

Gregg,
Looks like a good variety! I'll add @QRP and @QRPLABS to mine. Don't have the QDX yet, but I do have 4 QCX's and a couple of U3S.'
I'm going to try using the RS-HFIQ rig I have that pushes 4W today on JS8Call.

--Al
WD4AH


Re: QDX Isues with sWindows10 #qdx

 

Hi Evan,

Ok, well if you want me to check any setting on my Windows 10 laptop, just let me know. Per your question in another thread on how to listen to the QDX signal, you can do it from the Windows Sound Control panel. In Sound Settings -> Sound Control Panel ->?
1. Pick the Recording Tab
2. Select QDX Transceiver
3. Click Properties
4. On the List Tab, Choose Listen to this device

73,
Gregg W7GRM


On Sat, Nov 13, 2021 at 11:40 AM Evan Hand <elhandjr@...> wrote:
Greg,

I will try turning off the sleep command in Windows.? That would not explain why when then connecting to the Raspberry Pi that I have to restart the QDX multiple times to get the audio to work.

A further note:? I had a fellow build club mentor come over to my QTH to find out why his QDX would not show more than 2 watts on 40 meters.? In the process again we had issues with connecting his Windoes10 laptop PC.? We went to the Raspberry Pi and had to reboot 3 times to get it to connect with an audio signal, the CAT and even the input bar reported that it was working on the first 2 tries.

Based on that experience I went back and tried the 3 reboot tries with the Windows laptop and now it works.? I have left it running to see if it can duplicate the Raspberry Pi time of 12 hours continuous receive.? I did note that this time I ran the QDX on battery rather than one of my shack 13.8 volts power supplies.

I searched in the log file of the QDX and did not find any errors, so it is not an error that is reported in the QDX log file.

Will keep trying
73
Evan
AC9TU


Re: QDX Isues with sWindows10 #qdx

 

Greg,

I will try turning off the sleep command in Windows.? That would not explain why when then connecting to the Raspberry Pi that I have to restart the QDX multiple times to get the audio to work.

A further note:? I had a fellow build club mentor come over to my QTH to find out why his QDX would not show more than 2 watts on 40 meters.? In the process again we had issues with connecting his Windoes10 laptop PC.? We went to the Raspberry Pi and had to reboot 3 times to get it to connect with an audio signal, the CAT and even the input bar reported that it was working on the first 2 tries.

Based on that experience I went back and tried the 3 reboot tries with the Windows laptop and now it works.? I have left it running to see if it can duplicate the Raspberry Pi time of 12 hours continuous receive.? I did note that this time I ran the QDX on battery rather than one of my shack 13.8 volts power supplies.

I searched in the log file of the QDX and did not find any errors, so it is not an error that is reported in the QDX log file.

Will keep trying
73
Evan
AC9TU


Re: QDX TX power was almost zero.

 

Hi just measured my C2 and it 1.67??F so 25% down, so will replace.

73


Andrew G8UUG


Re: QDX issues: please include info: #qdx

 

John,

Thank you, I have done that in the past.?

The issue is how to do it in the field where I would not have the rig.? I would use my ZM-2 manual tuner when I work out how to hear the signal at the same time that I am connected to the QDZ.? I did read a post on how to do that here somewhere.? I may also try it with the signal level bar to see how that works.

73
Evan


Re: QDX issues: please include info: #qdx

 

On Fri, Nov 12, 2021 at 06:09 AM, Evan Hand wrote:
I do not have an antenna for 30 or 80 meters that does not require a tuner and am not comfortable in using the output of the QDX to trigger the MFJ auto-tuner that is required for the Ultimax 100 random wire antenna that I do have for 30 and 80.
Evan, you can use your main rig to trigger the autotuner. Once its found a match on 30 or 80, swap the main rig out for the QDX. It will see a matched antenna at that point.
?
--
John AE5X


Re: QDX #qdx

 

Here is the link to the thread

/g/QRPLabs/topic/86737876#74070

Hans said in this thread that it would be a few weeks before the parts would be ready for another round.

I think that the timing would be around Christmas to early next year


Re: JS8 QSO Party this weekend

 

Here's a helpful (and short) video for using groups in JS8:

--
John AE5X


Re: QDX IC7 fouls case #qdx

 

Fyi, I tried all orientations of both sides of the case and none of them would fit for me. It appeared that the board cut from the panel had more clearance on one side compared to the other. It ended up being an easy few minute fix anyway.

73,
Gregg

On Sat, Nov 13, 2021 at 10:02 AM Mike Besemer - WM4B <mwbesemer@...> wrote:

I wonder if everyone who is experiencing this is trying the board in both directions using both halves of the clamshell.? I find that there is plenty of clearance in 3 of the 4 possibilities, with only one snagging the slightest amount.? I¡¯m guessing this is a discrepancy in the manufacturing of the clamshell, not the PCB.

?

Mike

WM4B

?

?

From: [email protected] [mailto:[email protected]] On Behalf Of Gregg Myers
Sent: Saturday, November 13, 2021 11:50 AM
To: [email protected]
Subject: Re: [QRPLabs] QDX IC7 fouls case #QDX

?

I also had this issue with sliding the QDX board in the case due to not enough clearance with one of?the ICs. In my case, a few minutes of careful filing? with a small file allowed the board to slide into place.

?

73,

Gregg W7GRM

?

?

On Sun, Nov 7, 2021 at 1:28 AM Alan G4ZFQ <alan4alan@...> wrote:

>? IC7 is just about flush with the board edge.

Attached picture shows my cut. Done with a cheap Dremel-like tool. About
30 minutes of cutting..

QDX now working although like some others I get some strange self-test
results.

73 Alan G4ZFQ