【AD9833をオーバー・クロックで使う】 abstract I will now attempt to overclock the DDS-IC AD9833. According to the datasheet, the upper clock limit of the AD9833 is 25MHz. My guess is that 25MHz is too low. In my tests, the AD9833 worked fine even with a clock of over 100MHz. I will get a clean 30MHz signal from the AD9833 DDS module.Now the $2 DDS module has a new value. (2020.12.30 de JA9TTT/1 Takahiro Kato)

Photo : 2021.02.06 14:46 JST

【回路：中華カウンタとプリアンプ】 I made a kit for a frequency counter. This kit was purchased by mail order from China. It was only $2.9-. The frequency counter was lacking in input sensitivity as it is. So I will build a pre-amp to increase the sensitivity. I put an amplifier on it and it started counting at an input of about 100mV. This is very practical.  (2020.07.05  de JA9TTT/1  Takahiro Kato)

【自作好きHAM用のWindows10 PC】  < Abstract > Support for Windows 7 has ended, so I can still enjoy  "Hand making Rigs" with Win 7 PC.  But I decided to move to Windows 10 because of the need to connect to a network environment safely.   Unfortunately, my old PC couldn't update to Win 10.  So I bought a used, updated laptop. Also, I should install some apps for the HAM who loves "Hand making Rigs".

【ALINCO DM-330MVの修理】 abstract I repaired an Alinco DM-330MV power supply. The failure of that power supply was mainly due to overheating and unstable output voltage.I got the cooling fan from amazon and replaced it. I also corrected the contact failure. The method is very simple. Switch a few times. Let the variable resistor slowly rotate a few times. This is the only way to solve the

 【ebayでお買い物は？】 【ebayって？】 コロナ禍であまり出掛けられません。　まあ、大して気にしなければ良いんでしょうが、気持ちは若いつもりでも若くはありませんからね。　感染は気になります。　それで、通販を楽しむことになるんですが少し幅を広げたいと思います。 　最近の電子工作は、国内の通販だけでなく中華通販を含めて部品調達の範囲は幅広くなっています。今まで見つけられなかったようなアイテムが簡単に手に入ったり、思いがけずお買い得なことも珍しくありません。　ご存知の通り、信用に関しては国内通販に比べてイマイチな部分もあります。しかし、それなりの注意を払えばなんとかなるものです。 　　　　　　　　　　　　　　　　　　　☆ 　最近になってebay（イーベイ）を本格的に使い始めたので様子を書いてみたいと思います。すでに利用中の人も多いとは思いますが、もしまだでしたら如何でしょうか

【ローバンド用アンテナを改造す】   The low-band antenna I'm using needs to be modified. This is because Japan's Amateur Radio Band (HAM Band) has been changed.　The 160m band of the Top Band has been extended to the lower frequencies. First, I add about 2 feet of test leads to both ends. Then I look at the transfer of the resonant frequency. I modified the antenna according to the results of that

【MC3340Pを使った低周波AGCアンプ】   I made an Audio-frequency AGC amplifier with MC3340P, an IC for electronic volume control made by Motorola. Even if the input signal changed by 60dB, the change in output was limited to only 6dB. It would be suitable for a direct conversion receiver (DC-RX) or an Audio frequency amplifier for an Autodyne receiver. And it can also be used as a compression

【アンテナ：160mバンドアンテナを最終調整】   This article is a continuation of the low band antenna modification.　I've been experimenting with this antenna for two months now with a temporary response. As the result was good, I completed the modification. I soldered the extension of the antenna element. As a result, the operation was very stable. It seems that a proper response is still necessary.   (

【ECL-ICの使い方ノート（１）】   Are you familiar with the logic IC family called MECL?　 MECL is the nickname of Motorola's ECL-IC family. It is characterized by high speed and low noise generation. I will use MECLs a few times on this Blog. The first time I make a crystal oscillator using a MC10116P. This oscillator will be used as a clock oscillator in next experiment.   (2020.05.23   de