NA7RH - Bob

Scottsdale, AZ

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The very neat and compact NA7RH vintage shack.

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Bob at the operating position and live on 3870.  Xmtr is a single 6DQ5, modulated by four 1625's in P-P/parallel, both homebrewed from 1950's-era ARRL Handbook designs (see below).  Rec is a Knight R55 circa 1961.  Funky Eico scope monitors mod levels.  SSB rig is an Icom 735.

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The 6DQ5 Transmitter was originally built as a novice rig by Bob in 1962 upon being licensed as WN5FNJ in El Paso, Texas.  See PDF write-up below for the complete story.

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The back view of the 6DQ5 xmtr shows the band-switching  plate tank circuitry and scrounged power supply components. 

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The bottom view of the transmitter showing circuitry installed by 15-year-old WN5FNJ and preserved as an artifact of youthful inexperience.

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Circuit details and complete history of this 40+year-old transmitter that holds its own on the 80- and 40-meter AM nets. (~1Meg)




 



Schematic diagram of 6DQ5 xmtr - click picture for full page.  See below for complete Handbook article in PDF format.

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Complete ARRL Handbook article on 6DQ5 Transmitter in PDF format. (~925KB)  
   




 



The Push-Pull/Parallel 1625 modulator, rear view.  Power supply sold separately.

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Top View of modulator.


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Bottom view of modulator showing classic, neat-as-a-pin, component layout and point-to-point wiring.

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Schematic diagram of push-pull/parallel 1625 modulator - click picture for full page.  See below for complete Handbook article in PDF format.

(Click here for full-page diagram  ~200K)

Complete ARRL Handbook article on Push-Pull/Parallel 1625 Modulator in PDF format. (~760KB)

 Bob describes his career as VQ9RH to David, W6PSS






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