nobcha23のABブログ Airband receiver kit BLOG

エアバンドレシーバーキットの組み立て、改造を手掛けます Assemble and remodel Chinese airband receiver kit

Arduinoを使ったデジタル局発のデバッグ実験継続中 I'm doing digital local oscillator experiment still.

Arduiono互換基板のProlificチップ問題を回避するため、秋月Arduino UNO互換基板でプログラム書き込み、チップを付け替えデバッグと言う実験方法で推進中です。






As my arduino compatible PCB being with Profilic old pirate chip, WIN 10 driver update function is effecting badly to change new one and the mew one rejects fake chip. So I
shall correspond to this issue and I write soft on the other Arduino PCB and exchange ATMega tip. It takes much for debugging and replace software.

Nevertheless I had come to be able to monitor the nearest airport daily radio communication steadly. Please refer my latest sketch as linked and circuit diagram.

I'm just wondering that AGC signal is adequate for S-meter souce. Today I had checked AGC voltage comparing with HRD-737 rexeiver RSSI value. The HRD-737 and Chinese receiver kit are sharing same ANT signal with T-port BNC connector.

Surely AGC voltage is not well representing signal strength.






BTW, I had connected 30dB LNA on front end of the Chinese receiver kit. It brings more signal with more noise. Also there is more effected by IM or other channel intervened.

I think that more gain should be with narrower band range to avoid harmfull noise.



Si5351a with 25MHz Xtal