It is not confortable for assembling into a case that LCD&KEY shield is. I changed LCD to i2c LCD. As a result Arduino UNO is controlling all devices via i2c buss as a block diagram. I'm showing you i2c circuit of LCD mojule and key pad mojule.
As i2c LCD mojule is connecting with 4 wire cables, I could easily furnish it into case as next task.
In spring I had tried to improve pass band characteritics for PCB pattern style front end filter. And I found that to bend the capcitors effcted better characteristics for that.
最近RFワールドNo52を買って、nano VNAの取り扱いを勉強してみたので、その勢いをかってフロントエンドフィルターの特性をチェックし、特性改善テクニックを再現してみます。 Recently I bought the magazine of RF world for reading nano VNA articles. After then I had achieved experiment to measure junk parts dummys and homebrew dummys. With momentum I should try to check PCB pattern coil measurement.
しかし、この受信機の回路構成では局発が不安定です。そこで、デジタル方式の局発を作り、外部から供給することにしました。 Then I had found that this kit weekness was unstable local oscillator. I had started trying to make up digital controlled oscilltor.
その6-外部局発入力 Arduino制御でSi5351aを使う、XTALフィルタで低ノイズ、高感度。スケルチフィーリングも改良。 To ease to develop digital controlled oscillator I had changed the micon from PIC to Arduino. And also I adopt Xtal filter to improve sencitibity and low noize.
To ease debugging I had changed CPU into Arduino UNO. So I should prepare connection board bedween SWs, LCD, receiver, Si5351a breakout PCB. I'm studying to introduce functions by showing video.
There are 8 functions by entering 4 function keys. 1. On turning on memorized frequency is recovered and you can tune by rotary encoder with step frequency.
2. Long time pushing of F function key effects to store current frequency into EEPROM.
3. When STEP function mode you can select 6 kinds of step frequency.
4. Long time pushing of STEP function key effects to store current step frequency into EEPROM.
5. SCAN key is calling up memorized channel frequency of 50 kinds.
6. Long time pushing of SCAN key brings to scan memorized channel frequency of 50 kinds in turn.
7. Memory key provide memory number selection.
8. Long time pushing of Memory key brings to store the current frequency into directed memory channel.
There are many remodeling from original receiver kit and I will show you block diagram of set. The below picture shows connection of parts in the case.