开云体育

ctrl + shift + ? for shortcuts
© 2025 开云体育
  1. QRPLabs
  2. Messages
Expanded Topics Messages Polls
Date
Re: Tone or birdie every 500 Hz in USB mode

 

开云体育

My guess is that DIGI mode has a wider bandwidth so more noise. This will cause AGC to cut the gain a little bit and the spurs will appear reduced.

Tony
AD0VC

From: [email protected] <[email protected]> on behalf of Erik Larson via groups.io <kd7ykq@...>
Sent: Wednesday, April 2, 2025 11:27 AM
To: [email protected] <[email protected]>
Subject: Re: [QRPLabs] Tone or birdie every 500 Hz in USB mode
?
For some reason I cannot get audacity to record from the QMX.. But WSJT-X sees it fine (yes, I closed WSJT-X first before trying Audacity). So no audio recordings but another picture. Mel, mine sounds very similar to yours.
?
?
I have confirmed that the pulsating tone noise at 1Khz was from the GPS module, as with it removed the noise at 1Khz is markedly reduced. I will run it this way in the morning and see if it is better able to decode MSK144 without that persistent pulsating noise at 1KHz. I still see less of these noise lines in DIGI mode than in either USB or LSB, so I think there is something different with the RX audio? in DIGI that might help with USB also if I can figure out what the difference is.
Re: V6 Sythesiser PCB link wire

 

Well it’s a lovely job. ??
Only noticed it under high magnification !?
Re: SSB audio distortion #qmx #SSB Firmware beta 1_01_003 release #qmx #ssb

 

Hi Mehmet,
?
Everything looks for me. I have no ideas now. I don't have a QMX+, instead, a QMX HB version and a QMX LB version. And 80m is the only band I had trouble with.
--
73, de BD8BTE
op: Lun Yang
Re: How to replace Q507

 

Steve, if your solder iron has enough power (at least 50 W but better a bit more) you may do this:
  1. Desolder L502.
  2. Apply ChipQuick low temp solder to the two pins of Q507.
  3. Take a bit of flux on the metal of Q507 opposite to the two pins.
  4. Take a blob of normal solder with your iron on this metal of Q507 and wait 5 or 8 (or 12) seconds or so until you could take Q507 away. Because of ChipQuick the heat coming through Q507 to the pins is enough to melt this solder.
  5. Remove all ChipQuick from the solder pads for the pins.
  6. Don't remove the solder from the pad for the body of Q507.
  7. Apply a bit flux on the solder pad for the body of Q507.
  8. Hold the new Q507 in place using tweezers and heat Q507 like in No. 3 and 4 until you feel Q507 is swimming on the solder.
  9. Remove the solder iron and hold Q507 in place until it's fixed.
  10. Solder the two pins.
  11. Solder L502.
73 Ludwig
Re: SSB audio distortion #qmx #SSB Firmware beta 1_01_003 release #qmx #ssb

 

Hi Lun,
?
The phase error plot doesnt complete for most of the bands, not just 20m. All of the plots just look random zigzags and never the same on consecutive runs. Some are just a straight lines going across the top of the screen and these seem to complete ..
?
This is what I get on 20m..
?
?
?
No Tx
?
During Tx
?
Mel, M0KMD
?
?
?
?
Re: Help ID QDX Digital voltage and band option

 

Power supply voltage does not matter for RX. It only makes a difference on TX. You could try and figure out how the output transformer is wired, but that is difficult without removing it. I would suggest powering it at 9V and seeing what the power output is. If it is a 9 V unit, power should be 4-5 W on all bands. If it is a 12 V unit, power will be about 2-3 W.?
--
73, Dan? NM3A
Re: Qmx plus rev 2 not powering up

 

Azgael, please check schematics for QMX+ Rev. 2 / 3 page 1.
Gate of Q101 together with LIN_REG_EN is connected via R101 to "+12V". With pressed vol-encoder and not running controller LIN_REG_EN is pulled to around the voltage at "+12V". After the controller gets VDD via IC101, starts to run and VDD is proper generated via Q109 the controller will pull LIN_REG_EN low to around 0 V.
?
Checking schematics Rev. 4 for QMX you will find nearly the same things but additional R115 from LIN_REG_EN to GND, forming a voltage divider 0.5:1. This pulls LIN_REG_EN for the start only to 50% of "+12V".
?
But if you would see also only 50% of "+12V" at LIN_REG_EN of your QMX+ maybe R115 is hidden somewhere in the "deep parts" of QMX+ schematics.
?
73 Ludwig
Re: Tone or birdie every 500 Hz in USB mode

 

For some reason I cannot get audacity to record from the QMX.. But WSJT-X sees it fine (yes, I closed WSJT-X first before trying Audacity). So no audio recordings but another picture. Mel, mine sounds very similar to yours.
?
?
I have confirmed that the pulsating tone noise at 1Khz was from the GPS module, as with it removed the noise at 1Khz is markedly reduced. I will run it this way in the morning and see if it is better able to decode MSK144 without that persistent pulsating noise at 1KHz. I still see less of these noise lines in DIGI mode than in either USB or LSB, so I think there is something different with the RX audio? in DIGI that might help with USB also if I can figure out what the difference is.
Re: QMX+ rev 3 freezes shortly after boot

 

On Wed, Apr 2, 2025 at 01:24 AM, @Ludwig_DH8WN wrote:
Michael, please don't switch on your QMX+ in the moment. I will send more information later today.
73 Ludwig
RR! Will hold off on any more tests/debugging until I hear from you ?
Re: Gibberish characters appended onto end of Message 1

 

I had a similar experience. After deleting and re-recording the messages, it has not re-appeared.?
--
73, Dan? NM3A
How to replace Q507

 

After the great BS170 meltdown on my QMX, I'm down to replacing Q507 (Q503 and the BS170's have been replaced and look good). I do not have a hot air rework station - only ChipQuik. It looks like the drain is a pad, not directly accessible with a soldering iron.? Suggestions on how to replace Q507 with the materials I have ?
?
73,
Steve, N2IC
Re: SSB audio distortion #qmx #SSB Firmware beta 1_01_003 release #qmx #ssb

 

Stan,
?
My supply voltage is 12V, and I always use a 12V supply. The plot on 80m never comes to 2000 on the x axis, no matter how I play with the band configuration. After I disabled "20/80 BPF TXswap", the plot is still not complete as you saw, but the audio is good now.
--
73, de BD8BTE
op: Lun Yang
Re: SSB audio distortion #qmx #SSB Firmware beta 1_01_003 release #qmx #ssb

 

Lun, the first plot you showed here, with values out to 2000 on the x-axis may work fine, and give you good audio, even though the plot is not smooth.?
?
I presume your supply voltage was around 9V? (corresponds to about 2000 on the x axis).
?
The reason is, as I have verified by experiment,? that all of the values across the plot need to be initialized to avoid distortion in the audio, up through your full supply voltage range.? When the calibration does not complete,? leaving part of the plot unpopulated, audio distortion results.
Re: Gibberish characters appended onto end of Message 1

 

Is there a straightforward way to delete a message? Any special characters one has to put at the end of a message to prevent this?
?
Re: #qmx #SSB Firmware beta 1_01_003 release #qmx #ssb

 

Replying to my own question here!? I don't think the Icom 705 microphone can be made to work as the PTT and microphone output are connected together.? My guess is when you press the PTT on the microphone this applies the 3.3V feed to the microphone and powers it up.
?
However, I have discovered that a Baofeng* micriophone works perfectly and has the connections in the correct order on the 3 pole plug.? I say "perfectly" in the sense I can set a suitable gain using the microphone test.
?
*? and possbly a Yaesu microphone as well but I haven't tested this but I can find micriophones for sale which say they are suitable for Baofeng and Yaesu.
?
John
M0WIV
Re: ProgRock2 programming??

 

On 02/04/2025 14:33, Tom Smith via groups.io wrote:
How does it work without some DC going to pad 6 of the unit? It seems the unit would need the pad 6 to be connected to a voltage source.
Tom,

Yes, pin 6 or 12 needs say 5-12 volts to power the Progrock's 3.3 volt regulator
But the output of the 5351 pin 7 must not have an external voltage connected. If there is voltage a capacitor is required.
Ground is connected separately.

73 Alan G4ZFQ

.
Re: SSB audio distortion #qmx #SSB Firmware beta 1_01_003 release #qmx #ssb

 

Hi Mehmet,
?
I think the calibration procedure relies on both TX and RX. Is your RF/LPF scans look good on 20m?
?
And transmitter voltage should be near 0V when not transmitting.
--
73, de BD8BTE
op: Lun Yang
CW Practice / Rag Chew

 

开云体育


On 3/31/25 I had a CW practice / rag chew session on 20 meters. I worked one station:

Date / Time Call Bnd Frequency Mode Power Rec Snt Name SPC# Off Comments
3/31/2025 13:27 NM1I 20 14.047 CW 75 599 569 Butch MA 13:53 K3 at 75 watts 100 ft sloper doublet

Conditions were OK. SSN = 111, SFI = 171, A = 6, K = 3.

My next CW practice session will be April 04 at 09:00 EDT / 13:00 UTC on 20 meters.?Anyone and everyone is welcome. This practice is intended for operators who are new to CW or they need some practice. IT DOES NOT MATTER HOW POOR YOUR CW IS. Mistakes are OK. Poor fists are OK. Slow speed is OK. Really slow speed is OK. This practice is meant for you to improve your CW. I will do my best to adjust to your skill level. Operate at any power level. If several stations show up, I will operate as a round-table control station. I will do it as a round-table so everyone gets a chance to transmit. Please listen to my directions.

Details:
Date - April 04 2025
Time - 09:00 EDT ?13:00 UTC
Band - 20 Meters

How to find me - I will find a clear frequency and call CQ. Go to the Reverse Beacon Network and search for my call sign AB8DF.


That will tell you what frequency I am on. Tune your station to that frequency and if you hear me give me a call. If there is a QSO in progress, please wait for a break in the action. Then send your callsign. If I hear you, I will invite you to join the QSO and start a round-table QSO.

Reply to this email if you have questions.

IT DOES NOT MATTER HOW POOR CW IS

Ed
AB8DF_._,_._,_
QMX+ Volume

 

discovering more things on the rig. I finde, that the min. audio volume is still quite high but could not find a setting to alter that ( apart from muting it)
--
Martin
DK3UW
Re: Gibberish characters appended onto end of Message 1

 

I had this also, just deleted and re-entered the message and that fixed it. Weird.
1 - 20 of 140189