QRPp contacts, QRPp QSO

2009/12/03                       日本語は下にあります。  ve3cgc@hotmail.com


“ QRPp contacts “    QRPp  QSO


The Michigan Mighty Mite (the MMM ) is a one transistor Xtal controlled QRPp transmitter generating about 300mW to 400mW.   The key parts required are as follows:

(1)   transistor 2N2222 or equivalent, one required

(2)   resistor 10K ohms, one required

(3)   resistor 27 ohms, one required

(4)   capacitor 0.05 micro farad, one required

(5)   variable capacitor 365pF, one required

(6)   Xtal, 7Mhz freq., one required

(7)   Homebrew coil, one required

The schematic diagram can be found in internet websites under “ 500mW CW Transmitter” by “VE7OUC” as well as KC6WDK.


I up-loaded the pictures on my MMM, 40m and 20m version under “the MMM” in Dec. 3, 2009 in the album of this blog.  To enlarge the picture, please click the image.



QRPp contact #1:

I built the Michigan Mighty Mite(MMM20), 20m version, in Feb. 2007.  There is a story of the MMM20 in my blog, “2007/Mar/04”.  It generates 80mW only and I was disappointed with the power because I was not sure if I could make any contact at the time.  Since the MMM20 was made, no test QSO was made because the condx on 20m band has been poor and I had no chance for QSO.


On Oct. 27, 2009, I finally made my first QSO successfully with this MMM with VE1BA, John,  in Kingston, NS (about 1,000KM or more away from my QTH) with RST 549.  Obviously I was so excited because I have tried sending “CQ” hundreds of times in the past and no one came back.  But I was sure one day I would make a contact with 80mW of power.


I was using a triple bazooka I design and homebrewed.  The height is about 4.5m (14 feet) but SWR shows almost 1.0, well balanced.  John was using Yaesu FT-817, 5w out, and a 3 ele Yagi beam.   After every QSO with the MMM, I have been amazed with the capability of a small transistor.  And this time I was even more surprised and impressed with the power of 80mW generated by a small black transistor on the bread board HI.   So I waited for 2years and 7 months from building to the first QSO.  That is a kind of fun for QRP.



QRPp contact #2:

In Dec. 2004 at the Christmas holiday, I built my first MMM for 40m band.  The MMM40 did not work for nearly one year till Dec. 2005 because I misunderstood the leg positions on the transistor.   Finally the MMM40 generated about 300mW and I went on air with 300mW.  This MMM40 became dead in 2009 , no longer oscillating so I re-worked and re-wired in Feb. 2009.  Now it generates 350mW on 40m band.  I experimented and homebrewed the coil on my MMM so as to be able to go on 80m, 40m, 30m and 20m back in 2005 and my MMM40 is a multi-bander QRP.


On Oct. 29, 2009, I checked in the CW net controlled by KC5GXC, Pete, with the MMM (350mW of pwr) and he gave me the report of 449 which was not bad.  He is located about 1,000 KM or more, straight south from my QTH in Poplarville, in the Mississippi state, U.S.A.  I was using a loop antenna at my backyard up 25 feet high.   My wife does not allow me to have high antennas, HI.   As an old ham, I am more than happy for having wire antennas at low height above ground for the safety reason.  More stories for the MMM can be read in this blog on “2006/Feb/16” and “2006/05/18”.







In Japanese



1石トランジスターの送信機を自作して、CONDXをみて、電波を出しています。 PWR100mwから300mwですが、面白いQSOが出来ます。 最近のQRPpQSOを書きます。 自作の送信機はミシガン マイティー マイト(MMM)と呼ばれ、部品の数も少なく、手持ちの部品箱にあるようなもので、組み上がります。 部品表は上の英語の部分にありますが、組むのも簡単で、私は2台、MMM4040m)とMMM2020m)を自作しました。 写真はこのブログのアルバムの2009123日の「the MMM」にあり、写真をクリックすると、大きくなり、良く見えます。 Google のサーチエンジンに “ 500mW CW Transmitter” VE7OUC KC6WDK “Michigan Mighty Mite” (ミシガン マイティー マイト) をタイプするといろいろなサイトがあり、配線図なども見つけられます。



その1: MMM2020072月に組み、以来condxが悪く、テストのQSOも出来ませんでした。 本年1027日、運良く、VE1BA ジョーン、カナダ ノバスコシア州と80Wで、自作のトリプル バズーカ アンテナでRST 549をいただきました。 27ヶ月も待って、初めて出来たQSOですから、とてもうれしかったです。 PWRが少なく、QSOは出来ないかなあと、思ったこともあり、あらためて、MMMの実力を感じました。


その2: 私は7.050Mhz1200 UTC、にCWのネットに出て、チェックインします。 本年20091029日にMMMPWR 350Wでチェックインしてみました。 NCSKC5GXC ピート、(Poplarville, Mississippi 州 U.S.A.)でRST449 をいただきました。 当局からの距離は多分1000KMくらいはゆうにあると思います。 やはり、MMMのすごさに驚き、送信トランジスターをじっと見て、ラジオの不思議さを感じました。 この私のブログ “2006216 “2006518にもMMMの話がありますので、読んで下さい。





はやし ひろ  VE3CGC


This entry was posted in ハム ラジオ、アマチュア無線、ham radio, amateur radio. Bookmark the permalink.

One Response to QRPp contacts, QRPp QSO

  1. Unknown says:


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s