Category Archives: ham radio, amateur radio

A 72ohm to 50ohm broadband toroidal balun

2008/12/24               日本語は下にあります。 “ A 72 ohm to 50 ohm broadband toroidal balun “  「72オーム / 50オーム 強制バランの製作」   I designed and homebrewed a broadband toroidal balun for 72 ohm balanced to 50 ohm unbalanced for the Hallicraft HT-18 (assembled in 1949).  The balun was … Continue reading

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A QRP dummy load

2008/10/02             日本語は下にあります。   “ A QRP Dummy Load “  「QRP ダミー ロード」   I built a dummy load for QRP transmitters, primarily for my homebrew projects.  I used ten pieces of 100 ohm resistors connected in parallel.  So the resistor value is theoretically … Continue reading

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T/R Switch

2008/09/11                                     日本語は下の方にあります。   “ A T/R Switch   送信、受信切り替えスイッチ”     I operate QRP homebrew transmitters and built a transmitting / receiving switch last month. ( The schematic I made by "WORD" is not shown somehow here.  Sorry.)           Jack … Continue reading

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“The Tube QRP that did not work.”

2008/08/10                                   日本語は下の方にあります。   “The Tube QRP that did not work.”   I built my first tube QRP transmitter, 2W 20m monobander 6BA6, 6AQ5, Xtal controlled in 2005.  The picture of this transmitter is shown in the album of this blog under … Continue reading

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