Date   

Re: QCX-SSB: SSB with your QCX transceiver

Manuel; DL2MAN
 

@Dean:
Thanks for your feedback. As you might have figured out already, english is not my native language. So it is of great value for me, if a native speaker gives such a feedback.
In german this would be "fett", so I thoght "fat" would be apropriate :) But now, as you mention it, I remember the term "bold". Thanks again.

Regarding C35: Valueful input. Will mention it.

L5/6 are 100µH in Guidos Schematic, and I didn´t re check those. Thanks. Will change this also.

In the next revision of manual, there will be also Mic and Key Wiring, as Guido thought, it might be helpful.
If someone else realized somthing missing or wrong, please give me a feedback.

@Christiaan:
I asked Guido to have a look at it.
As far as I can see from your Picture, you did not do the full modification since T1 is in Place and C1 is also in Place. So you did not do the SDR Mod ?
I can´t give you much input, since I went all the way (Multi Band, SDR RX and SSB TX).

73 Manuel; DL2MAN


Re: Very ow reception sensitivity/low Peak BPF/Different C1 from all pictures #qcx40 #alignment

Jelle
 

Hi Alan,

Thank you for your reply.

The table is taken with C1 in middle travel on the ground side. That should have a Peak value for a frequency. I thought I would find that with changing the alignment frequency as in the table. I do understand that there can be multiple peaks. However, if I have found a peek at 07,500,000 than a value of scale 04 reading 6+2 bars is far to low and indicate I have an issue elsewhere. Are you suggesting I should continue with lower frequencies?

Your suggestion for a 12 V supply is a good one too. However, currently not at hand.

Hope you haven't given up on me.

Have you seen this type of cap in the kits before? Does this also is fully closed when drop at centre leg? And fully open when opposite? All the above is assuming this to be the case.

Many thanks, Jelle


Re: QCX-SSB: SSB with your QCX transceiver

Christiaan PA3FUN
 

Hi All.

I did my best to build QCX-SSB as neatly as possible on a unused R4 board.

I loaded R1.02a.

Display showed 1 line of white blocks, other line blank.

Following the (excellent) "troubleshooting" section on qrp-labs website I ended up suspecting the (i2c-communication with the) Si5351a.

I stripped Guido's code to the bare minimun, just enough to initialize the LCD and write the version-info to it, see below.

Do basically ALL interaction with the Si5351a eliminated from the code.

Now the LCD awaked, see photo attached. So, processor obviously okay & up-and-running, and wiring processor<->LCD okay.

I checked I2C-wires, SDA and SCK. No short-circuit, perfect connection from the Si5153a-chip to the processor. 1K pull-ups in place.

The Si5351a -power measures 3.5V. The 27MHz oscillator works (as observed thru freq.counter &oscilloscope).

No short-circuits between any other pin of the Si5351a.

However, no output. And, after, reloading the full code-base, hang-up again. Tried the same with Hans' rev 1.5 (yes I know, not intended for this modified board) with same result. Display top-row white blocks, bottom-row blanks.

 

HELP......

 

 

void setup()
{
  digitalWrite(KEY_OUT, LOW);  // for safety: to prevent exploding PA MOSFETs, in case there was something still biasing them.


  initPins();

  lcd.begin(16, 2);  // Init LCD
  for(i = 0; i != N_FONTS; i++){  // Init fonts
    pgm_cache_item(fonts[i], 8);
    lcd.createChar(0x01 + i, /*fonts[i]*/_item);
  }

 
  show_banner();
  lcd.setCursor(7, 0); lcd.print(F(" R")); lcd.print(F(VERSION)); lcd_blanks();

}

void loop()
{
}


Re: Very ow reception sensitivity/low Peak BPF/Different C1 from all pictures #qcx40 #alignment

Jelle
 

I am looking at T1 voltages and R2 and R3 should bring T1, windings 6 and 7 to mid voltage. Not 1.77V? I'll check that now.


Re: Very ow reception sensitivity/low Peak BPF/Different C1 from all pictures #qcx40 #alignment

Alan G4ZFQ
 

Jelle,

C1 has long travel with Peak BPF of scale 04 bars 7+2. Travel includes fully open (I think). I also read in the group to set C1 in middle position and find max BPF reading with the below results.
If the capacitor is fully open then that means resonance is too low. Remove turns.
Maybe your tests did not go low enough?

8.1 Aling frq 8.7 Peak BPF
07,020,000 scale: 03 bars: 12+2
I took the DC voltage reading table from the manual and completed it first with an external DVM and after firmware upgrade to 1.05v, took it again with internal DVM (with lower supply voltage). Please see the results below:
I find these confusing with different supply voltages.
Use 12V and check with the internal meter, compare with the chart. Effects on the audio output are not documented.
A quick glance looks OK. In any case are there other problems?

73 Alan G4ZFQ


Re: U3S SUB-MESSAGE PROGRAMMING

Hans Summers
 

Hi Peter

JT65 sends 13 characters. 

If you want to send successive JT65 messages, with different segments of the message, you would need to split the Message string into 13-character sets, with the delimiter character between them. 

Then you would need to configure a separate slot in the transmissions (16 slots available), one for each of the sub-message segments. Each transmission lets you link to a desired sub-message. 

73 Hans G0UPL
http://qrp-labs.com

On Fri, May 8, 2020 at 8:41 AM sturtp2001 <vk2ztv@...> wrote:
Hi All,
I am having problems with sub-messaging for use in JT65A, the project is a multi-mode beacon - PI4, CW ID, JT65A CW ID (full message) and then WSPR with a few CW (short version) as padding to get the time slots right. So far all good except the JT65A picks up the start of the full message which is: DE VK2RHV QF57SC MOUNT SUGARLOAF NEWCASTLE.
The decoded JT65A message is DE VK2RHV Q.  The mode selection is JT65A        00 0.

The message menu is spaces(_) __ DE_VK2RHV_QF57SC_MOUNT_SUGARLOAF_NEWCASTLE__ followed by the delimiter character the full block QF57 then the full block, I assume it knows that this is sub message 00 .
What am I doing wrong?
Regards
Peter VK2ZTV
   
l


Re: Very ow reception sensitivity/low Peak BPF/Different C1 from all pictures #qcx40 #alignment

Jelle
 

C1 picture attached
 
Many thanks, Jelle


Very ow reception sensitivity/low Peak BPF/Different C1 from all pictures #qcx40 #alignment

Jelle
 

Hi all, I hope to find help with getting QCX through alignment.

PCB Rev 5 Firmware 1.05v

C1 has long travel with Peak BPF of scale 04 bars 7+2. Travel includes fully open (I think). I also read in the group to set C1 in middle position and find max BPF reading with the below results.

8.1 Aling frq 8.7 Peak BPF
07,020,000 scale: 03 bars: 12+2
07,000,000 scale: 03 bars: 12+2
06,500,000 scale: 03 bars: 7
06,000,000 scale: 02 bars: 8+2
08,000,000 scale: 03 bars: 10+2
07,500,000 scale: 04 bars: 6+2
07,300,000 scale: 03 bars: 9+2
07,800,000 scale: 03 bars: 6+2
07,400,000 scale: 03 bars: 12+2
07,600,000 scale: 03 bars: 14
07,550,000 scale: 04 bars: 6
07,525,000 scale: 04 bars: 5+2
07.575,000 scale: 04 bars: 6

Max at 07,500,000 of scale 04 reading 6+2 bars. I realise that we could have multiple peaks and I have not found the real peak.

I have checked RF continuity and T1. I am not sure about QSD. However, RF could already be too weak. I checked R43 120k. What else could be an issue?

I took the DC voltage reading table from the manual and completed it first with an external DVM and after firmware upgrade to 1.05v, took it again with internal DVM (with lower supply voltage). Please see the results below:

Location Example ext DVM int DVM Comment
+ supply terminal 11.98 9.45 8.91 As I already mentioned: a 12V supply
Clk0 test pin ~1.70 1.59 1.5 ~ 1.7 The Clk0 pin in normal operation has a 3.3V peak-peak squarewave with 50% duty cycle. The DVM is measuring the average of that. Measuring here makes a lot of nasty noise in the audio.
Clk1 test pin ~1.70 1.59 1.5 ~ 1.7 The Clk1 pin in normal operation has a 3.3V peak-peak squarewave with 50% duty cycle. The DVM is measuring the average of that. Measuring here makes a lot of nast noise in the audio.
Left side of C2 3.40 3.39 3.40 This is the voltage of the Si5351A supply, pins 1 & 7
Right side of C2 0.00 0.00
Right side of D2 4.96 4.97 5.00 This is the +5V regulated supply
Regulator Top 4.98 5.02 7805 VO
Regulator Mid 0.00 0.00 7805 GND
Regulator Bot 9.10 8.56 7806 VI
T1 pins 1, 2, 3 & 4 0.00 0.00 0.00
T1 pins 5, 6, 7 & 8 2.36 2.53 1.77
Top side of C43 2.28 2.53 1.83 C43-46 are the QSD integrating capacitors. The voltage across each one differs slightly. The following measurements show these small differences.
Top side of C44 2.44 2.53 2.35 slow beat on audio
Top side of C45 2.42 2.53 1.83 slow beat on audio
Top side of C46 2.30 2.53 1.61 Audio muted at measurement
IC5 pin 1 2.64 2.55 2.60 IC5a output, the pre-amp I output
IC5 pin 2 2.46 2.50 2.52 slow beat
IC5 pin 3 2.26 2.50 1.57 Audio muted at measurement
IC5 pin 4 0.00 0.00 0.00
IC5 pin 5 2.28 2.50 1.83 slow beat
IC5 pin 6 2.46 2.50 2.52 slow beat
IC5 pin 7 2.44 2.54 2.54 IC5b output, the pre-amp Q output
IC5 pin 8 11.67 9.15 8.54 This is the supply voltage minus the voltage drop caused by the reverse polarity protection diode D3
IC6 pin 1 2.44 2.57 2.52 IC6a output
IC6 pin 2 2.44 2.57 2.52 slow beat (audio volume drop)
IC6 pin 3 1.63 2.57 1.83
IC6 pin 4 0.00 0.00 0.00
IC6 pin 5 1.55 2.57 1.69
IC6 pin 6 2.44 2.57 2.54 slow beat (audio volume drop)
IC6 pin 7 2.44 2.57 2.54 IC6b output
IC6 pin 8 11.67 9.14 8.54
IC7 pin 1 2.64 2.61 2.60 IC7a output
IC7 pin 2 2.64 2.61 2.60 slow beat (audio volume drop)
IC7 pin 3 1.99 2.61 1.95
IC7 pin 4 0.00 0.00 0.00
IC7 pin 5 1.89 2.61 1.87
IC7 pin 6 2.64 2.61 2.60 slow beat (audio volume drop)
IC7 pin 7 2.64 2.61 2.60 IC7b output
IC7 pin 8 11.67 9.14 8.54
IC8 pin 1 2.46 2.56 2.54 IC8a output
IC8 pin 2 2.46 2.56 2.54
IC8 pin 3 0.65 2.56 0.69 Audio muted at measurement
IC8 pin 4 0.00 0.00 0.00
IC8 pin 5 0.67 2.56 0.69 Audio muted at measurement
IC8 pin 6 2.48 2.58 2.56
IC8 pin 7 2.48 4.58 2.56 IC8b output
IC8 pin 8 11.67 9.14 8.54
IC9 pin 1 4.84 4.80 4.84 IC9a output
IC9 pin 2 4.84 4.80 4.84
IC9 pin 3 0.65 4.48 0.67 Audio muted at measurement
IC9 pin 4 0.00 0.00 0.00
IC9 pin 5 0.67 2.53 0.67 Audio muted at measurement
IC9 pin 6 2.44 2.55 2.52
IC9 pin 7 2.44 2.55 2.52 IC9b output
IC9 pin 8 11.67 9.14 8.54
IC10 pin 1 5.83 4.59 4.25 IC10a output
IC10 pin 2 5.83 4.59 4.26
IC10 pin 3 5.83 4.59 4.26
IC10 pin 4 0.00 0.00 0.00
IC10 pin 5 4.21 4.56 3.05
IC10 pin 6 3.94 4.56 2.74 Audio muted at measurement
IC10 pin 7 5.83 4.59 4.25 IC10b output
IC10 pin 8 11.67 9.14 8.54
LCD pin 1 (leftmost) 0.00 x 0.00 LCD VSS supply pin
LCD pin 2 4.94 x 4.98 LCD VDD supply pin
LCD pin 3 0.57 x 0.89 LCD Constrast
LCD pin 4 4.92 x 0.04 LCD RS pin
LCD pin 5 0.00 x 0.00 LCD RW pin
LCD pin 6 0.00 x 0.00 LCD E pin
LCD pin 7 1.08 x 1.52 LCD DB0 pin
LCD pin 8 1.08 x 0.00 LCD DB1 pin
LCD pin 9 1.06 x 1.52 LCD DB2 pin
LCD pin 10 1.04 x 1.52 LCD DB3 pin
LCD pin 11 0.00 x 1.53 LCD DB4 pin
LCD pin 12 4.94 x 4.96 LCD DB5 pin
LCD pin 13 4.92 x 0.00 LCD DB6 pin
LCD pin 14 0.00 x 0.00 LCD DB7 pin
LCD pin 15 4.41 x 3.82 LCD backlight anode
LCD pin 16 (rightmost) 0.00 x 0.00 LCD backlight cathode

I don't seem to have any issue with the display. I have gone through the rest of the alignment but think that low Peak BPF needs to be resolved first? All values were quite high.

I hope to get suggestion on what to look at next.

Many thanks Jelle


Re: QCX-SSB: SSB with your QCX transceiver

Dean Smith
 

Ok scrub C32 comment its grounded on topside of pcb! Just looked.


Re: QCX-SSB: SSB with your QCX transceiver

Dean Smith
 

Hi, Manuel, all,
Thought I'd add a couple of pointers to documentation for rev5 pcb, that people might find helpful when following the instructions.
Firstly the value (fat if changed) word fat would be better as bold.
C35 should be soldered slightly higher off the pcb to allow you to solder the pin nearest IC2. Otherwise it will be uber tricky!
C32 the ground pad on the Pcb looks as if it's floating. I'll assume the minus lead of the capacitor needs a board ground.
L5, 6 100uh. 47uh are supplied. I take it that's a typo.
Best
Dean (G7EOB)


Re: U3S not getting decodes #u3s

Alan G4ZFQ
 

but despite many attempts with modifications, foam insulation, cooling and calibration I couldn’t make it work. It's too unstable.
Allan,

All my attempts have shown reasonable stability at least as far as HF without any real effort.
Some, like you, have said they have not got it stable.
My reckoning therefore is that there is something that is preventing stability. I'd try changing the crystal, maybe some of those are more sensitive to temperature changes than others.
Drift was a common problem in the early days when the U3 used a DDS but I do not see many posts about unstable Si5351s on HF. Yes, above 30MHz may be more of a problem, I do not know.

73 Alan G4ZFQ


Re: U3S

Alan G4ZFQ
 

I bought a U3S kit it 2015 but was unable to build it due to illness.
Ive just dug it out of the box but cant seem to find any instructions online. Anyone know how i can get them?
Gary,

http://www.qrp-labs.com/ultimate3/u3s.html Says you need 4 files.
For a start what board revision? (Maybe go down to Instructions: translations and previous PCB versions?)
Then firmware version? Or, maybe update?

73 Alan G4ZFQ


Re: U3S not getting decodes #u3s

Allan Nelsson
 

The reason for the curved lines is instability. My original U3, ran with reasonable stability at 30 metres, but after upgrading to the U3S with relay board and LP filters for multiple bands, it went wrong. My intention was to run with successive switching between more bands including  6 metres, but despite many attempts with modifications, foam insulation, cooling and calibration I couldn’t make it work. It's too unstable. So in the future I decided to run WSPR with the Rfzero (www.RFzero.net), which is rock stable. And fortunately the fine QRPlabs filter board can be re-used. :-)

73, Allan


U3S

Gary Swain
 

I bought a U3S kit it 2015 but was unable to build it due to illness.
Ive just dug it out of the box but cant seem to find any instructions online. Anyone know how i can get them?

TIA Gary


Re: U3S not getting decodes #u3s

Hans Summers
 

See also App Note AN001 http://qrp-labs.com/appnotes on the topic of reducing drift. This can make it usable on 6m even without the OCXO. 

73 Hans G0UPL
http://qrp-labs.com

On Fri, May 8, 2020 at 10:01 AM James Anderson <james21170@...> wrote:

Hello Brian. 

I would 2nd what Ken has just said. 

The 6m waterfall has huge drift. I use the OCXO to prevent this. 

I can get Zero drift on most TX periods but occasionally. Park mode utilised etc. 
Can you receive your own signal to check for drift?
I also use Argo to see a better interpretation of my signal as it happens. 

It’s as we all know an unpredictable band and also the output power of my 2nd U3S struggles a bit on output power. Very low but perfect to drive the10w linear.
This U3S is an early version.

I’m working on the 10w linear to give it a bit more Oomph but even then I’m not expecting any miracles. 


All the best with it. James. 


Re: U3S not getting decodes #u3s

James Anderson
 

Hello Brian. 

I would 2nd what Ken has just said. 

The 6m waterfall has huge drift. I use the OCXO to prevent this. 

I can get Zero drift on most TX periods but occasionally. Park mode utilised etc. 
Can you receive your own signal to check for drift?
I also use Argo to see a better interpretation of my signal as it happens. 

It’s as we all know an unpredictable band and also the output power of my 2nd U3S struggles a bit on output power. Very low but perfect to drive the10w linear.
This U3S is an early version.

I’m working on the 10w linear to give it a bit more Oomph but even then I’m not expecting any miracles. 


All the best with it. James. 


Re: Notes and Feedback on QCX Kit That Just Arrived

Trystan G0KAY
 

The parts list isn't on the parts list either.

I had a boss once, who returned and grammatically corrected my memo that I sent to him excusing my berevement leave due to my father's passing.

Trystan


Re: QCX 20M with very low power

Alan G4ZFQ
 

Charles,

My mistake I meant decrease. My seemed stable as low as it was.
You were correct the first time.
Low power (~1 watt) with power increasing as the capacitors get warm is the symptom reported by those who have had faulty capacitors.
Note that replacements can be the same type. Get from a reliable supplier. Hans has changed his supplier so the problem should not occur on new kits.

73 Alan G4ZFQ


Re: No Lights on the QLG1 ?

KEN G4APB
 

Hi Paul,
the red led is across the 5v supply so should come on regardless if the gps is working or not. Have you fitted the leds the correct way round? 
Have you connected the 4 way connector up backwards? Easily done.
Until you get the red light on, nothing else will work.

73 Ken G4APB


Re: QCX-SSB: SSB with your QCX transceiver

Manuel; DL2MAN
 

Hello David,

Red outlined sections are changed in comparison to original schematic.
The missing sections are..... Missing ;)

Please read Guidos info from the project page.
(His link named other Infos) and you should be good to go.

73 Manuel DL2MAN