Ten Tec Omni V Station

Pictured above is an electronic device for converting insectival prestidigitation, iambic compression, and transduced, bovine scat laden, torrid, air into high frequency, modulated, wave forms designed to break the cupric, atmospheric, boundary for world wide distribution....Otherwise known as the fantastic, much acclaimed, soon to be world famous,W5TOM  Ten Tec Omni V station.

It was built in 1989 by Ten Tec and is possibly the best crystal-mixing receiver they ever made.  It has two roofing filters, a 2.4kc and a 1.5kc that can be cascaded.  In the second IF it has 2.4kc, 1.8kc, 500c and, 250c crystal filters.  Needless to say it is very selective and sports wonderful low noise RX circuitry.                

It contains the Omni V, the Hercules II 500 Watt Amplifier, the 238 Tuner, the 961 Power Supply, a Tectronix 222 Scope, MFJ 447 Keyer, a Bird 43 Peak reading Wattmeter, an Apple Shuffle for auto CQ calling, a large black olive PTT switch, and a Astron 30M Power Supply.  The amp and the rig run on a 12v deep cycle battery which is paralled with the Astron and a Schumacher SEM 1562A battery maintainer.  When the station is in use, the Astron is turned on.  It can keep up with the drain on the battery very easily, and the six feet of 14ga wire connecting it to the battery keeps the current in the 3 to 15 amp range with it's resistive voltage drop.  When not in use, the Schumacher keeps the battery fully charged and happy as a clam.

The Microphone is a W5TOM original with an electret element, which is the best match for the Ten Tec four pin rigs.  I call it my D-102.   The work lamp is a vintage Tensor 110v model. The station works exceptionally well on both CW and SSB


 

Here is the way the station looked before the Hercules II amplifier and other assorted Ham candy was added.


 

On the CW side I have a 100th Anniversary Vibroplex Bug and a set of Brown Brothers paddles that have been converted to magnetic.  They also feature a set of custom made finger pieces.  The bug has a custom made weight and finger pieces. .  This doubles the amount of weight and makes it possible to operate as low as 14 wpm.  The scope monitors both the received and transited signals by sampling the RF out and audio on channels 1 and 2 respectively.  In the pix you see the TX RF and the side tone.  The Tektronix 222 does just as well on SSB.  The bug and the keyer are paralleled into the rig, so I can switch in the middle of a word if desired...keeps 'em guessing.  


 

     

Frequency accuracy and readout calibration is the biggest complaint by modern users of this rig, who think that all stations tuned must have zeros on the readout when clarified.  Here is my solution. This is the band oscillator door I added so the frequency calibration can be easily achieved.  It is the aluminum strip in the middle with a screw on each end.  This mod gives access to the row of trim caps without disassembly and introduction of cold air that would distort the adjustment.  The frequency readout on this rig is very accurate and stable after 1/2 hour warm up.


 

   

This is the only contact with the outside world.  It is an electrical outlet and plug.  It makes an easy quick disconnect and is the only ground for the station, which is three ground rods and the house electrical ground.  The antennas are the all band dipole and the vertical full wave loop for 17 meters.  They work well and no interference with the surrounding station or household electrics is experienced.


 

 

Here is the connection from the 50 Ohm coax to the Radio Works 4:1 balun and to the homemade 2 inch ladder line.  The clamp on ferrite chokes probably don't do anything, but they look much better here than in the junk box.


 

 

The sun is reflecting off of the Omni antenna.  It is a asymmetrical dipole at 40ft. that is about 83ft. on one side and about 12 ft. on the other.  It is fed with homemade 2"ladder line.  Also in the pix is the "SGC Vertical" and a 10m/20m coax fed dipole. The 17m loop is in the tree at the left. The antenna works very well, and is the type of antenna that is meant to be tuned with the TT 238 tuner.  So the old station is true to the design and period.