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Re: QCX 5th birthday

 

Good thing you took the time to clean up the first design Hans! That would have been very difficult tokit and build! :))
Re: QDX Only 1.5 Watts on 20m band #qdx #power

 

Do not continue this thread....I could fix this issue by moving the L4 turns as close as possible on the toroid. Tweaking the turns fixed it. Now I got 4.5Watts on 20 meters and over 5Watts on 30m...?
Thanks for Evan's support here.?

73 de µþ¨¦±ô²¹
Re: QDX Small output power in some of the bands #qdx #power

 

Ahhhh... Evan, this worked. I condensed the turns on L4 as much I could and Now I got about 4.5Watts output power on 20 meters. On 30meters even higher than 5volts.?
Many thanks for your proposal. This was really helpful.?

73 de µþ¨¦±ô²¹ HA4BM
Re: QDX with Bluetooth? #qdx #bluetooth

 

The "FT-897 Bluetooth dongle" (well, not really a dongle) is a TTL Serial to Bluetooth (serial protocol) device - NOT a USB device at all.
My best guess (or at least the version I made for my FT100D) uses a standard "Serial Bluetooth Module" (I used a Sparkfun Bluetooth Mate).
The FT-897 Bluetooth dongle uses the old fashion Baud (standard values), Data (7 or 8 bits), Parity (standard values), Stop (standard values).

Although USB does have the word "Serial" in it (a better term would be "Universal Streaming Bus"), it is not 'directly' compatible with the old COMM connections that the FT-897 uses.
The "normal" FT-897 USB interface (like RTSystems USB-62C)? uses an extra chip (typically an FT232 or the like) to convert the COMM style data to USB style streaming data.
This FT232 chip (or CP210x) has a driver (for the attached computer) that defines the USB stream as it is formatted from the radio COMM port.

NOTE: The QDX actually has 2 streams coming over the USB connection -> Audio and COMM.
??????????? Even if you did get the "FT-897 Bluetooth dongle" to work, it could only do CAT control.? You would not get audio.
--
Rob KB8RCO
Re: QDX Small output power in some of the bands #qdx #power

 

Hi Evan,?

I checked the LPF selection.?
The cathodes are near 0 on the selected LPFs the un-selected ones are on 11V level. (not 5V)

It is following the configuration:
+---Band configuration-------------------------------------------------------+
?|? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? |
?|? Band name (m)? ? ? 80? ? ? ?60? ? ? ?40? ? ? ?30? ? ? ?20? ? ? ?0? ? ? ? ?|
?|? Audio gain (dB)? ? 60? ? ? ?60? ? ? ?60? ? ? ?60? ? ? ?80? ? ? ?0? ? ? ? ?|
?|? Frequency min.? ? ?1400000? 4000000? 6000000? 7500000? 10500000 0? ? ? ? ?|
?|? Frequency center? ?3573000? 5357000? 7074000? 10136000 14074000 0? ? ? ? ?|
?|? Frequency max.? ? ?4000000? 6000000? 7500000? 10500000 14500000 0? ? ? ? ?|
?|? Sweep start? ? ? ? 3200000? 4000000? 5000000? 8000000? 11000000 0? ? ? ? ?|
?|? Sweep step? ? ? ? ?20000? ? 50000? ? 50000? ? 50000? ? 100000? ?0? ? ? ? ?|
?|? BPF number (0-3)? ?0? ? ? ? 1? ? ? ? 1? ? ? ? 2? ? ? ? 3? ? ? ? 0? ? ? ? ?|
?|? LPF number (0-2)? ?0? ? ? ? 1? ? ? ? 2? ? ? ? 2? ? ? ? 2? ? ? ? 0? ? ? ? ?|
?|? Transmit? ? ? ? ? ?ENABLED? ENABLED? ENABLED? ENABLED? ENABLED? DISABLED? |
?|? PTT +5V positive? ?DISABLED DISABLED DISABLED DISABLED DISABLED DISABLED? |
?|? PTT grounded? ? ? ?DISABLED DISABLED DISABLED DISABLED DISABLED DISABLED? |
?|? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? |
?+------------------------------------------------------------Ctrl-Q = Quit---+

The band sweep on 20m band looks like this:?
12 |.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?. ? ? ? ? .? ? ? ? ?.? ? ? ? ?.
? ?|.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?**? ? ? ? . ***? ? ?.? ? ? ? ?.? ? ? ? ?.
? ?|.? ? ? ? ?.? ? ? ? ?.? ? ? ***.? ? ? ? ?.? ? **? ?.? ? ? *? .? ? ? ? ?.
? ?|.? ? ? ? ?.? ? ? ? ?.? ?***? ?.? ? ? ? ?.? ? ? ***? ? ? ? ?.
? ?|.? ? ? ? ?.? ? ? ? ?.***? ? ? .? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.*? ? ? ? .
? ?|.? ? ? ? ?.? ? ? ?***? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?. *? ? ? ?.
? ?|.? ? ? ? ?.? ? ***? .? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? *? ? ? .
? ?|.? ? ? ? ?.? **? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ?*? ? ?.
? ?|.? ? ? ? ?. *? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? *? ? .
? ?|.? ? ? ? ?**? ? ? ? .? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? *? ? .
? ?|.? ? ? ? *.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ?*? ?.
? ?|.? ? ? ** .? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? *? .
? ?|.? ? ?*? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ?* .
? ?|.? ? *? ? .? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? *.
? ?|.? ?*? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?*
0? |.. * . . ... . . . ... . . . ... . . . ... . . . ... . . . ... . . . .*. . .
? ?|.**? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.*
? ?|*? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?. *
? ?|.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? *
? ?|.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ?*
-4 |.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? ? ? ?.? ? *
? ? ----------------------------------------------------------------------------

The top is at 14MHz aprox, the max value is on 12...
How is your sweep looking like??

L4 seems to be evenly tweaked... I adjust the turns see if that helps.?

µþ¨¦±ô²¹
?
Re: QDX with Bluetooth? #qdx #bluetooth

 

Just out of interest, I modified my FT-897 bluetooth dongle to fit the USB A-B lead connection to the QDX. However, although I could pair with the device and two basic serial COM pots were allocated under Windows 11, using Putty or Hypertermnal, I was unable to get any data connection to the QDX.
I also tried using my QLG2 GPS module that has a serial output, but no data seen. I tried various baud rates (default being 9600) to no success.
This never worked very well with Hamcomm and my FT-897 so I was happy to modify it.
Not really sure why this did not work..was just an exercise really, but if anyone has some ideas to try, they are welcome.

73 Ken G4APB
QDX Only 1.5 Watts on 20m band #qdx #power

 

Hello Team,?

I got QDX 12Volts version. Using 50 ohms dummy I?measure:
4.5Ws on 80m (850mA)
5Ws on? 60m (930mA)
5.2Ws on 40m (1A)
5Ws on 30m (970mA)
1.5Ws on 20m (470mA)
(not a very precise PWR meter)

All is fine except the PWR on the 14MHz.?

Do you have a suggestion how could I troubleshoot the 20m bands. I did remove already one turn from the LPF but it did not help. Any suggestion is very welcome.?

73 de µþ¨¦±ô²¹ HA4BM





?
Re: FOR SALE: QCX-mini (20m) Rev 3 and two U4B's

 

All items have been sold - thanks.
Re: QDX USB problems - new build #building #qdx

 

Using 3s lipo batteries, just over 12v. Tried 2 sets and same behavior.
Re: QCX loud noise on power on

 

Hi Nico. It sounds to me like you are getting an oscillation in one of the audio gain stages. Please measure the DC voltage on pins 1 and 7 of ICs 5,6,7,8,9 & 10. Those might point to the general location of the problem. Good luck .. Ron
Re: QDX rev 3a board PCB fault #qdx

 

On 22/08/2022 14:47, pa2pim@... wrote:
Finally current consumption in Rx-mode will drop several mA (Forgot how many)
Pim,

Under the fault condition I think about +20mA has been mentioned.
And receive has been reported as very poor, audio very low.

73 Alan G4ZFQ
FOR SALE: QCX-mini (20m) Rev 3 and two U4B's

 

I won't be getting to these projects.

for 20m (no case) - $45
Two - $90 for the two

I pay shipping; US only please. PP, money order or Zelle

TNX/73,

John AE5X
Re: QDX rev 3a board PCB fault #qdx

 

By following the instructions in the manual you will not be " fixing"? C41. Without the the modification the junction of IC9B-5, C74 and R37 is grounded. Physically that occurs at the grounded site of C41. Following the instructions will remove that unwanted ground and IC9B-5 will come back to around half of Vcc. That brings the IQ processing back in balance which results in improved unwanted sideband rejection. Also all kind of " regular" spurs in the waterfall display will be gone. Finally current consumption in Rx-mode will drop several mA (Forgot how many)

rgds,
Pim
Re: QCX 5th birthday

 

Hi Steve

> Is that an on/off power switch in the pre-prototype??

Sharp eyes. Yes. And a 5mm yellow LED next to it. Normally when I am working on any dev lash up, I include both a power switch such as this, and a LED. The reason is that it makes it fast to make modifications. I don't have to plug/unplug power cables or switch on/off a power supply (which may well be in use for powering more than one project). The LED I find very valuable as a visual indication (read: WARNING!) that a circuit is powered. The LED tells me I should switch off before poking around?with my soldering iron.?

When working on hollow state projects I do the same thing, but in this case a neon across the B+ / HT. In this case that neon indicator is then telling me to switch off before poking around with my fingers OR the soldering iron :-/?

73 Hans G0UPL



On Mon, Aug 22, 2022 at 5:10 PM Steve Z <zabarnick@...> wrote:
Is that an on/off power switch in the pre-prototype??

Steve N9SZ

Re: QDX BPF LPF #qdx #bpf #lpf

 

I have got something very weird going on here, I need to do some more testing of my board.
I get the same response for 20m RF scan regardless of the settings of BPF and LPF. There are no L12 taps or capacitors for 80m to 30m inc.
Time to get the VNA out.
Re: QCX 5th birthday

 

Is that an on/off power switch in the pre-prototype??

Steve N9SZ
Re: QDX BPF LPF #qdx #bpf #lpf

 

IC3 changed with cbt3253.? It has the resistance between those pins.??

I need some guidance on how to set frequencies in the Band setting menu to get proper filter response.? I understand there was an issue.?

73 Bojan S53DZ
Re: QDX with Bluetooth? #qdx #bluetooth

 

Hello,

Disclaimer: I am not a qualified engineer or professional programmer.

I was looking at the schematics of the QDX and was thinking of this idea, of adding a Bluetooth. I think hooking up a Bluetooth module to the unused I/O pins of the STM32 would be possible. For instance, a reasonably cheap CSR8645 module provides audio in/out over I2S as well as Bluetooth Serial profile for CAT control.

Since the module would be an add-on, existing USB functionality would be retained. I guess the caveats would be that the Bluetooth firmware on mentioned Qualcomm chip would have to be customized with their SDK and a software menu would need to be added for switching between USB/Bluetooth audio (or maybe auto-sense?).

What I'm not entirely sure about however, is how a connected Bluetooth device would behave, since audio recording over Bluetooth normally works during a phone call. There are gaming wireless headsets with microphones however, so that must work somehow (I'm not completely familiar with Bluetooth profiles). Making a Bluetooth chipset work in that mode would enable bidirectional audio, thus solving this problem.

Regards,
George Sz
Re: No spots on wsrnet.org.

 

The problem is that those links require an end user to look for them.

They don't, they go straight to what wsprnet shows in the top left and corner
and then get confused.

The website really needs to include what I call the "direct tx freqs" too
in order to spoon feed the newbies who don't bother to read Hans's
manuals that also include these "direct tx freqs".

There can only be three causes of WSPRnot being decoded.

Timing. You can start to tx cycle upto about 6 seconds late and it will decode.
You cannot start a cycle even 1 second early, it will fail.

TX FREQ. If it's not within the 200Hz wide WINDOW then it will fail.

DRIFT. More than 4Hz and it will fail. This can be down to environmental factors.
An open PCB with air currents around the ref xtal will ruin things.
A ref xtal will tend to suffer less drift in hotter climates.
That's why TXCO / OXCO's exist ;-)


- 73 de Andy -
Re: QDX and 20M and 40M QCX minis for sale SOLD

 

Both Minis and the QDX have been sold.

Thank you and enjoy.

Phil, K3UT
54461 - 54480 of 144317