# Ratin

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5

1. ## Is there a way for measuring or know, input impedance of MICIN1 pin of Allwinner H3?

Special Thanks Ford!. for direct use of An Electret Mic , I think your are right. But how about indirect input(Pre Amplified Microphone Signal to MICIN1 pin)? I mean like whats I did, when we connect Output of an PreAmplifier to MICIN1,Which Determine F-3db freq? As you know, output impedance of Amplifiers are very low, so I think input resistanse of MICIN1 pin should be considered . Maybe that Input impedance combined with decoupling Cap (in this case 100nF and in my schematic C6=1uF) make HPF ? So whats your Idea? What is Maximum capacitor(C6) value that i can use for this circuit?
2. ## Is there a way for measuring or know, input impedance of MICIN1 pin of Allwinner H3?

Hi Ford ! thanks for your answer. Do you said that because of Matching Impedance Theory? But there is a problem! we need a Decoupling Cap in input of MICIN1 pin of Allwinner; That i saw in here it is 100nF. [see attached image] With that 100nf and even 4Kohm, we make a HightPass Filter with F-3dB = 400 Hz!? So, Sounds like somthing go wrong! because the Amount of That HPF must be designed to acheive as low as possible frequency (Like 1 Hz or even lower).
3. ## Is there a way for measuring or know, input impedance of MICIN1 pin of Allwinner H3?

hi all! my problem is simple! Is there a way for measuring or know, input impedance of Microphone input pin (MICIN1) ? in case C.H.I.P , but because it's prossesor is Allwinner A13(=R8), it must be same. thanks in advance
4. ## NanoPI NEO / AIR

Hi All, As you know, with Default OS presented by FreandlyARM, Many apps & Features are disabled. for example, it hasn't nano editor, python3 and either it's most known libraries,flexibility for installing most of new apps, and so on. I really can't tolerate this situation that i had to try many ways, just for installing one python3 library!! . while your Beta OS is extremely better in this fields, but it is suffers too from Somethings like AUDIO Output(& maybe input?), Usb device compatibility , OTG support, and long boot time. So,you will be glad all, if you can work harder to make better one, that you can support, and we can relay that.a version with good performance and application. I Know that you can. Go Ahead leaders! (Sorry for poor English )
5. ## NanoPI NEO / AIR

Hi Dear Tkaiser! Thank you for your great work in Modifying Linux to prepare a better OS for our IOT projects. But, there is some problem with beta images that released in Armbian Site that i couldnt solve them till now : OS Checked : Armbian_5.17_Nanopineo_Debian_jessie_4.6.7 Armbian_5.17_Nanopineo_Debian_jessie_4.7.2 Armbian_5.17_Nanopineo_Debian_jessie_3.4.112 Armbian_5.17_Nanopineo_Ubuntu_xenial_3.4.112 1. Connecting WiFi Dongle (MAIN PROBLEM) : Mine is EDUP 802.11N Dongle that works properly in Raspberry pi B+, But in Any Armbian OS in Nanopi NEo , I cant use it. Error is : [ 52.823742] rtl8192cu: Chip version 0x10 [ 52.921565] rtl8192cu: MAC address: e8:4e:06:32:29:2d [ 52.927211] rtl8192cu: Board Type 0 [ 52.931436] rtlwifi: rx_max_size 15360, rx_urb_num 8, in_ep 1 [ 52.937967] rtl8192cu: Loading firmware rtlwifi/rtl8192cufw.bin [ 52.945062] usbcore: registered new interface driver rtl8192cu [ 52.951813] rtlwifi: Firmware rtlwifi/rtl8192cufw.bin not available [ 53.010557] Error: Driver 'rtl8192cu' is already registered, aborting... Dongle's LED not even turn on, let alone blink! 2. USB OTG Doesn't work in Armbian_5.17_Nanopineo_Debian_jessie _4.7.2 . may be additional setting needed in may Windows laptop for that? i dont know ! 3. Alsamixer, Amixer, aplay,.... not installed or enabled by default in last beta version of Vanilla version. For must use of IOT , it is better tat be Enabled . Would you please give me some help for fix this problems?