Re: 3 tips for not blowing the finals of the QDX
#qdx
Hans,
do you plan to create a watertight enclosure?
This should work...maybe even for your competitions...
Giuseppe Marullo
IW2JWW - JN45RQ
PS: always to make some PI4 take a bath in it and overclock...never dared also because of FC77 prices
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Highest 4FSK Baud rate on the QDX?
#qdx
Hi all,
I just wondering what the hightest posable 4FSK baud is on the QDX is? (we do not have a baud limit in ZL)
I think I can get FreeDV running useing the 800XA mode (4FSK)
Thanks, Lilly ZL1LLY
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Re: Help with debugging QCX-mini for 20m
Thanks Ron,
I checked, and there doesnt seem to be continuity between the bottom two pins, although I do see the bit of exposed metal between the pins that looks like a connection.
Im going to keep digging through the schematic and see if I can come up with any other possibilities too, although I did do some heat testing (with my fingers) and found that it seems to be the L4 toroid and the Q1 transistor which are heating up.
73
Cal
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Re: Help with debugging QCX-mini for 20m
Cal, in looking at the photo you sent of the repaired board on the original thread, I see what looks like a short between the two bottom pins of the header. One of those is +5v and the other is ground. If there is truly a short there, you should remove it and try again. Might be your problem.
Ron
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For 250mW output, the current draw into my 5 volt regulator is about 200 mA. Running the transmitter (single BS170), LCD backlight on full, GPS running, and the relay board.
A LM317 linear regulator works well. I have a calculator for the resistors, if you need. The data sheet is great and I use the version with the extra filtering to keep any RF out of the supply lines.
--
---------
Paul KE7HR
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Re: Menu Select Key not working on QCX-mini
Good job Bob. Glad you got it going.?
On Sun, May 14, 2023 at 11:38 Robert Rabin < r.rabin@...> wrote: Hi Ron,
Heated the solder well on those 2 connections. Now have continuity and all the buttons are working!
Ron, thank you so much for your expert help! It certainly saved me a lot of time and anxiety!
-Bob
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Help with debugging QCX-mini for 20m
Hey everyone,
I had submitted a post about my issues after damaging some traces early, and now that I've repair those traces (although maybe to perfectly yet) I am having issues with power draw. There must be a short somewhere, but I'm having trouble finding it. When I plug the QCX-mini in I can feel the area near the transistors heating up quite a lot, and there is a faint ozone smell. I haven't let it run for too long in the fear that one of the transistors will fry. Also, I assume separately, the rotary encoder isn't functioning properly, clicking it works but using the dial it has no effect. I am pretty confident this has to do with my trace repairs.
I've watched the QCX troubleshooting video and read through the manual to see if I can figure it out, but I wonder if anyone out there might have an idea where I might look for a short that might effect the transistors?
73
Cal
VA3ZLA
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Re: Menu Select Key not working on QCX-mini
Hi Ron,
Heated the solder well on those 2 connections. Now have continuity and all the buttons are working!
Ron, thank you so much for your expert help! It certainly saved me a lot of time and anxiety!
-Bob
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Re: Menu Select Key not working on QCX-mini
Hi Ron,
Thanks! That's makes more sense.
Indeed, there's no continuity from pins 6 and 8 from the header to the control board.
Now my challenge will be to use a hot enough setting to solder a good connection.
-Bob?
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Roberto,
With a finals failure, there is a high probability of IC5 failing as a low resistance on the 5volt regulator IC2.? Carefully inspect the 74ACT08 IC5 for a blemish or surface heating.? If you are comfortable with SMD work, you could remove IC5 and see if the current on receive drops below 200ma.? Also, check on the IC2 temperature.? It should not be hot.
A quick test of IC5 with the BS170s removed (or L14 removed) measures the gate voltages on the BS170 finals.? They should be 0 volts receiving and 2.5 volts transmitting.? Use the Terminal transmitter test program to trigger transmission.? If you have an oscilloscope that will work at the transmitting frequency, you should see a 5-volt square wave with transmitting.
73
Evan
AC9TU
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Re: PROGROCK2 Not communicating w/MS 10 laptop
Hi Dale,?
You need to use something like PuTTY to communicate with the board. Check which serial port Windows assigned to the board and attempt to connect with PuTTY. You'll have to hit the return key once it appears to have connected in order to see the session, IIRC. Good instructions on the website as to how to make desired changes, but bottom line, it's a very minimalist configuration environment due to the chip in use.
73, Brock VA7AV?
On Sun, May 14, 2023, 7:05 a.m. Dale Mecomber < dalen2dm@...> wrote: Hi de N2DM, Dale May 14
I bought 3 progrock2's, when plugged into my win10laptop, all I get is an asscending dual tone that?
recognizes a device is connected. Nothing else. No wizard or acknowledgement on win explorer.
Any hints from others on this problem?
Thanks, Dale.
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Re: Newly built version 5 QDX high band transceiver not booting correctly problem
Yes, you can see the eprom file when it comes up emulating a drive.? You can change to an earlier version of the firmware and it will show up when you restart the QDX in a firmware update mode.? It appears to be accepting updates.
Here's what I'm seeing....when you first apply power the LED constantly blinks.? Nevee goes solid.
If you unplug the power and wait 10 seconds or so, reapply power the LED comes on solid and it is in the firmware mode.
Gary a.
Gary,
When you connect using the USB disk emulation, do you see the current version and EEPROM file in the folder?? There has been at least one case where the EEPROM failed and would not save the firmware or configuration data.
73
Evan
AC9TU
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Thanks Jeffrey
I'm in Italy.? I hope to find help with less DHL engagement :-) but, anyway, will take your offer under attention
I already checked Q6, and receiving current is 250 mA with L14 disconnected, so i suspect failure happened also in RX circuitry.
thanks in advance for any further suggestion
--
I2RWR
Roberto Ranzani - JN45mn
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Re: Newly built version 5 QDX high band transceiver not booting correctly problem
Gary,
When you connect using the USB disk emulation, do you see the current version and EEPROM file in the folder?? There has been at least one case where the EEPROM failed and would not save the firmware or configuration data.
73
Evan
AC9TU
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PROGROCK2 Not communicating w/MS 10 laptop
Hi de N2DM, Dale May 14
I bought 3 progrock2's, when plugged into my win10laptop, all I get is an asscending dual tone that?
recognizes a device is connected. Nothing else. No wizard or acknowledgement on win explorer.
Any hints from others on this problem?
Thanks, Dale.
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Re: Menu Select Key not working on QCX-mini
Hi Bob. No I¡¯m talking about the 8 pin header on the small board with the controls and buttons. Something could have changed after it was built and tested. If you follow the schematic you should see that you need continuity between pin 6 (third from the top on the right column) of the header to pin 26 (buttons) of the microcontroller. If you don¡¯t see it, then you need to check one segment at a time till you find the open. Also make sure you have 5v on pin 8 (lower right corner pin) of the header.?
If all of that looks good then the problem is likely on the controls board itself. Follow the schematic and find where the open circuit is.?
Ron
On Sat, May 13, 2023 at 21:39 Robert Rabin < r.rabin@...> wrote: Ron, is that the 10 pin male header on the board with the display?
As far as I can tell, the continuity looks good when it is connected to the other board.
This unit was purchased assembled.
Thanks, -Bob
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Re: Newly built version 5 QDX high band transceiver not booting correctly problem
Al,
Yes, I have gone over the board very closely with a jewelers eyepiece and it all look good.? Cleaned the rosin and found no changes in the symptoms.
Hope to ask Hans later this week while in Dayton.
Thanks for the input.
Gary a. - W0MNA
Gary,
Have you tried going over the board with a toothbrush lightly dipped in isopropyl alcohol? This is good practice for clearing up residual rosen on the board, but it can also help flush out small solder blobs and wire whiskers lurking on the PCB. I usually follow that up dabbing the board with a paper towel; that seems to leave less fibers hanging on protruding wires.
Very close inspection around the processor and EEPROM seems in order, too.
Good luck with the project!
--Al
WD4AH
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Re: Newly built version 5 QDX high band transceiver not booting correctly problem
Rick,
Good thought.? I tried a different power source with a good solid 9vdc under load and no change in the symptoms.? Also fed 12 volts into it which is still in the range but again no symptom change.
Thanks for the input.
Gary a. -W0MNA
Hi Garry.
?I had a similar issue with my low band version a few weeks ago.
It turned out to be a poor battery supply.
I built mine 9V and it wants a good quality of 9 volts!
Hth.
Rick.
DE G6UZT.
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OK Mike! That is progress. Good luck!
JZ KJ4A
Hi John. I have checked T202 first and found that it is incorrectly mounted on the pcb. This was corrected and now with 1v p-p on each driver gate I am getting some output albeit very low. I measured the signal on the drains of each driver and can see 2v p-p. I now need to check the position of T201 as you suggested. Can't believe I got this wrong twice.Mike
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Hi John. I have checked T202 first and found that it is incorrectly mounted on the pcb. This was corrected and now with 1v p-p on each driver gate I am getting some output albeit very low. I measured the signal on the drains of each driver and can see 2v p-p. I now need to check the position of T201 as you suggested. Can't believe I got this wrong twice.Mike
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Ronald Taylor
Paul Jorgenson KE7HR