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Saving battery current
#mods
#qcx
#supply
I am sorry to report that I had to remove the converter from under the QCX PCB. The voltages looked clean on my oscilloscope but I could hear harmonics of the switching frequency every 58 kHz on 20m.
I am sorry to report that I had to remove the converter from under the QCX PCB. The voltages looked clean on my oscilloscope but I could hear harmonics of the switching frequency every 58 kHz on 20m.
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By
Helmut, DK2ZA
· #41040
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Saving battery current
#mods
#qcx
#supply
Simply replace the existing 7805 with a Recom r-785.0-0.5. It's pin compatible and fits neatly where the 7805 was. Then reduce the the backlight supply current by changing R48 to 1.8 k (yep, seems hig
Simply replace the existing 7805 with a Recom r-785.0-0.5. It's pin compatible and fits neatly where the 7805 was. Then reduce the the backlight supply current by changing R48 to 1.8 k (yep, seems hig
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By
Ronan Cantwell
· #40574
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Saving battery current
#mods
#qcx
#supply
Excellent example of home-brewing! Very nice, Helmut!
Excellent example of home-brewing! Very nice, Helmut!
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By
Dennis Shelton
· #40541
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Saving battery current
#mods
#qcx
#supply
OOOps, I forgot to mention that the 7805 and R48 (270 Ohm) are of course left out now!
OOOps, I forgot to mention that the 7805 and R48 (270 Ohm) are of course left out now!
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By
Helmut, DK2ZA
· #40537
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Saving battery current
#mods
#qcx
#supply
Another way to reduce current is change R48, that determines the backlight brightness Increasing it lower the brightness and the current. The stock 270 ohm is 37ma, increasing to 1000 ohms lowers it t
Another way to reduce current is change R48, that determines the backlight brightness Increasing it lower the brightness and the current. The stock 270 ohm is 37ma, increasing to 1000 ohms lowers it t
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By
ajparent1/KB1GMX
· #40533
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Saving battery current
#mods
#qcx
#supply
Hi, I am using a battery of 12 cells in series giving 12 x 1.2 V = 14.4 V. The QCX needs 14.4 V for the analog circuitry and for the PA to provide an output of 4 W. The digital circuitry and the LCD u
Hi, I am using a battery of 12 cells in series giving 12 x 1.2 V = 14.4 V. The QCX needs 14.4 V for the analog circuitry and for the PA to provide an output of 4 W. The digital circuitry and the LCD u
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By
Helmut, DK2ZA
· #40532
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Saving battery current
#mods
#qcx
#supply
Hi, Reduce the battery pack to 10 cells and the current will be reduced as well as the voltage. Your output power will be reduced but not enough to make any practical performance changes beyond reduci
Hi, Reduce the battery pack to 10 cells and the current will be reduced as well as the voltage. Your output power will be reduced but not enough to make any practical performance changes beyond reduci
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By
Bill Cromwell
· #40531
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TX clicking / woodpecker
#qcx
#mods
Hi, I just added 1 uF to C6. At my QCX-20m, there was no noticeable increase of sensitivity. Checked this with low level noise source. 73 Axel, DF1ET
Hi, I just added 1 uF to C6. At my QCX-20m, there was no noticeable increase of sensitivity. Checked this with low level noise source. 73 Axel, DF1ET
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By
Axel
· #39767
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TX clicking / woodpecker
#qcx
#mods
Hi Hans :), Amazing what some real programming can do :). Lots of fun :).
Hi Hans :), Amazing what some real programming can do :). Lots of fun :).
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By
jmh6@...
· #39543
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TX clicking / woodpecker
#qcx
#mods
Very clever. Congratulations, it seems a rather ideal solution so long as the interupt doesn't create latency for some other item. Joe
Very clever. Congratulations, it seems a rather ideal solution so long as the interupt doesn't create latency for some other item. Joe
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By
Joe Street
· #39541
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TX clicking / woodpecker
#qcx
#mods
Hello Karlis, all I managed to solve the sidetone click by firmware alone... this article is now updated with 'scope screenshots: http://www.qrp-labs.com/qcx/qcxmods/sidetone.html#firmmod I am running
Hello Karlis, all I managed to solve the sidetone click by firmware alone... this article is now updated with 'scope screenshots: http://www.qrp-labs.com/qcx/qcxmods/sidetone.html#firmmod I am running
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By
Hans Summers
· #39540
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TX clicking / woodpecker
#qcx
#mods
Too late bro... I'm going to sleep now, to dream of abused PWMs and narrow slices of CPU time. And will have one more try in the morning... 73 Hans G0UPL
Too late bro... I'm going to sleep now, to dream of abused PWMs and narrow slices of CPU time. And will have one more try in the morning... 73 Hans G0UPL
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By
Hans Summers
· #39520
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TX clicking / woodpecker
#qcx
#mods
I know the feeling when the solution seems just around the corner, but let me not take away your time from QSX :)
I know the feeling when the solution seems just around the corner, but let me not take away your time from QSX :)
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By
Kārlis Goba
· #39519
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TX clicking / woodpecker
#qcx
#mods
Hello Karlis Yes, I tried various different things along these lines that you suggest. In the end after many hours I still couldn't make it work cleanly. It may be that some other interrupt with varia
Hello Karlis Yes, I tried various different things along these lines that you suggest. In the end after many hours I still couldn't make it work cleanly. It may be that some other interrupt with varia
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By
Hans Summers
· #39514
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TX clicking / woodpecker
#qcx
#mods
Hi Hans, I have an idea for the SIDETONE PWM signal, but it depends on how tight your timing/memory requirements are in your QCX code. You'd probably have to squeeze a high-frequency interrupt routine
Hi Hans, I have an idea for the SIDETONE PWM signal, but it depends on how tight your timing/memory requirements are in your QCX code. You'd probably have to squeeze a high-frequency interrupt routine
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By
Kārlis Goba
· #39510
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TX clicking / woodpecker
#qcx
#mods
Hi Karlis, all I *almost* made the sidetone click improvement in firmware too! I tried to play with the PWM signal, by arranging for its duty cycle to be 50% but for there to still be a 700Hz frequenc
Hi Karlis, all I *almost* made the sidetone click improvement in firmware too! I tried to play with the PWM signal, by arranging for its duty cycle to be 50% but for there to still be a 700Hz frequenc
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By
Hans Summers
· #39488
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TX clicking / woodpecker
#qcx
#mods
I'm so happy now that I made the effort to do the FW updates in situ with the USBasp it will make upgrading the firmware a breeze. Thanks Hans for the continued improvements. Paul DJ0CU.
I'm so happy now that I made the effort to do the FW updates in situ with the USBasp it will make upgrading the firmware a breeze. Thanks Hans for the continued improvements. Paul DJ0CU.
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By
Paul Harrison
· #39482
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TX clicking / woodpecker
#qcx
#mods
Hello again Karlis Yes I did have the idea of a resistor too and I tried it. Both on the LCD_RS line and on the SDA signal to the Si5351A. On the RS line made no difference. On the SDA line, a small v
Hello again Karlis Yes I did have the idea of a resistor too and I tried it. Both on the LCD_RS line and on the SDA signal to the Si5351A. On the RS line made no difference. On the SDA line, a small v
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By
Hans Summers
· #39481
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TX clicking / woodpecker
#qcx
#mods
Hi Steve Yes! Guido PE1NNZ told me! That's right, I remember now. Well it was a very good tip! While it was not directly the solution to the problem, it did point in the correct direction and so enabl
Hi Steve Yes! Guido PE1NNZ told me! That's right, I remember now. Well it was a very good tip! While it was not directly the solution to the problem, it did point in the correct direction and so enabl
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By
Hans Summers
· #39477
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TX clicking / woodpecker
#qcx
#mods
Hans, It was Guido Pe1nnz who gave you the hint. Yours, sleepily enjoying a beer with Alan at Schipol prior to flying home, Steve G0XAR
Hans, It was Guido Pe1nnz who gave you the hint. Yours, sleepily enjoying a beer with Alan at Schipol prior to flying home, Steve G0XAR
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By
Stephen Farthing G0XAR JO92ON97
· #39446
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