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<p class=MsoNormal><font size=2 color="#1f497d" face=Calibri><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>A
neběžà ti na to RPi náhodou OSMC, nebo Libreelec? Poslouchám to houkánà taky a
řekl bych že to vzniká v systému.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color="#1f497d" face=Calibri><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color="#1f497d" face=Calibri><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></font></p>
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<p class=MsoNormal><b><font size=2 face=Tahoma><span style='font-size:10.0pt;
font-family:"Tahoma","sans-serif";font-weight:bold'>From:</span></font></b><font
size=2 face=Tahoma><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>
Hw-list [mailto:hw-list-bounces@list.hw.cz] <b><span style='font-weight:bold'>On
Behalf Of </span></b>Michal Grunt<br>
<b><span style='font-weight:bold'>Sent:</span></b> Thursday, May 20, 2021 10:02
PM<br>
<b><span style='font-weight:bold'>To:</span></b> HW-news<br>
<b><span style='font-weight:bold'>Subject:</span></b> RušenĂ z podsvĂcenĂ LCD<o:p></o:p></span></font></p>
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12.0pt'><o:p> </o:p></span></font></p>
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<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>Mám na stole pospojovany bastl:<o:p></o:p></span></font></p>
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<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>Lipol baterka, DC/DC měnič na 5V, RPi Zero, 5" HDMI displej, malý
audio zesilovaÄŤ s PAM8403.<o:p></o:p></span></font></p>
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<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>ProblĂ©m je, Ĺľe asi obvody pro podsvĂcenĂ LCD zanasi do napájenĂ rušenĂ,
kterĂ© se projevuje pĂskotem v reproduktorech (takove vysokĂ© G) skoro nezávisle
na hlasitosti resp. je to slyšet i na nejnižšà hlasitost. Displej má regulacĂ
jasu tlaÄŤĂtkem a pokud jas stáhnu na minimum tak je piskot minimálnĂ i kdyĹľ
trochu slyšet je (pĹ™idánĂm jasu to zaÄŤne pĂskat vĂce mĂ©nÄ› stejnÄ› hlasitÄ› aĹľ do
100% a trochu to měnà tón). Pokud displej napajim samostatně z powerbanky tak
je to bez problémů (piskot tam neni). Projevuje se to i když neni audio vstup
zesilovace připojen k displeji a je "v luftě" (displej má svůj audio
vystup, kterĂ˝ jde z RPi po HDMI). To je asi tak všechno co jsem zatĂm zjistil.
Jak to rušenà vyblokovat? Zkoušel jsem 100nF i většà kapacitu (470uF)
pripojovat k napájenĂ LCD, ale bez vĂ˝sledku. Asi to bude chtĂt nÄ›co vĂce
sofistikovanejsiho.<o:p></o:p></span></font></p>
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<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
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<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>MG<o:p></o:p></span></font></p>
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