nobcha23のエアバンド受信機自作ブログ DIY airband receiver 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

R909-DSP2

R909-DSP1/2のTA2003各端子デジタルテスター測定電圧値を比較し不具合要因を探る Comparing the measuring value with the data sheets.

I could not find the cause of backgound noise from TA2003 or the former section. I shall compare the measuring value with the TA2003 data sheet listed. I measured all nodes of R909-DSP1 and R909-DSP2. However I could not claer this isuue. …

R909-DSP2のフロントエンドフィルターコイルについて About the front end filter for R909-DSP2

I will introduce the R909-DSP2’s front end filter. I used the 2-stage stagger for R909-DSP1. This time I adopted 3 stage Chebyshev characteritic filter. It is sharply high cut but there is deep ripple. Please look at the last photo. R909-…

R909-DSP2が何とか動き出す R909-DSP2 is scarcely working.

R909-DSP2 is a follower of R909-DSP radio and composed with TA2003+Si5351a+Si4732+TDA2822. I scarcely finalised debugging it. After winding coils it receives the signal from the airplane who is approacing to Itami airport. It could not re…