this is my home Amateur Radio Station setup.

I built a simple 1x2 rack and paneled it with 1/4"birch plywood.

it is powered by two computer power supplies in parallel. 

Shelves are removable, all radios, and power supplies are secured to the shelves.

Finally re-installed my radios in my F150 Ford pick up. I wanted to clean up the installation a bit. I used a over head storage/gun shelf I purchased through JC Whitney. I then obtained some light gauge metal the length of the shelf, had it bent. Then with careful measuring I cut openings for my cobra CB radio, Yaesu FT-100D, Z100 auto tuner, and the Bearcat scanner. I also drilled out all mounting holes for brackets and for attaching the metal cover to the shelf. everything is held together with 3/16" fasteners. (nut and bolt combos).  all wiring and coax is routed to centralized plug in play on back of shelf hidden from all view. 

CHEAP POWER SUPPLY

The other day I acquired a OKLA 500-ATX 500 watt computer power supply.  I did a little research  as I was wanting to build or modify this for Ham Radio.  What I found is that it is possible and relatively in expensive to modify this model.
i began to rummage through my electronics tool box for a 10 watt thermal resistor, a on /off switch, 2 330 ohm resistors. Then I went to radio shack for the binding posts,a chassis mount fuse holder, and 2 LED's.

Now to make this unit produce power it needs to see a need.  That's where the thermal resistor comes in.  I connected 5VDC to it and other end to ground. next I found the supply power lead (sp) on my unit its the grey wire. and located the power good (pgs) lead , on mine its the purple wire.  I connected each wire to a LED. the other end of the LED 's through a 330 ohm resistor to ground.  Then found the wire labeled on/off on the circuit board, on mine its the green wire and connected it to a on/off switch, and to ground.

Next I mounted my chassis fuse holder, and binding posts, then simply soldered the 12VDC wires (on my unit its the yellow wires) through the fuse holder and to the binding posts I wanted to use for 12VDC. then I connected the 5VDC (on my unit its the red)wires to a binding post. Then connected the black ground wires to the black or ground binding posts.

that's it!!  I secured the necessary wiring, sandbar resistor, and eliminated unnecessary wiring. put it back together and tested it. first verifying the supplied voltage and then powered a IC-208H V/UHF radio on the air at 5, 10, 25, and 50 watts.  reports were a flawless clean signal!

Latest in the tape measure yagi antennas

This author has taken the tape measure yagi antenna project one step further.  Completing another 4 element tape measure antenna, I  decided to try and stack the two yagi antennas 1/2 wavelength apart and co-phase the two together.
Remember when co phasing antennas, the feed lines are exactly the same length.  To achieve this, I changed coax feed line to LMR-400.
Preliminary testing is generating some good results.  Have been able to access distance repeaters that I was unable to with the rubber duck antenna on the HT.

This is the test station in operation.  HT is a Icom T2H with extension mic, on 1 watt output power.

tape measure yagi antenna

latest in my antenna designs and builds is a 4 element tape measure yagi for 2meters.  its compromised of a
41 3/8" reflector,
 driven element 17 3/4" each.
 1director 35 3/8",
 2nd director 33 3/8" .
boom spacing from reflector,  8" to driven element.
from driven element to 1st director 12"
from 1st director to 2nd  14"

8" AWG 14 gauge wire as a hair pin match. fed with RG 58U coax.

Fox hunting bidirectional loop

this type of antenna is a Receive Only antenna.  when hunting RF signals you are triangulating RF signal strength. you do not need to transmit.   This antenna is a simple one to build and it can be fashioned out of any type of wire from a coat hanger to brazing rod or even aluminum rod or copper tubing.   I fashioned this one from aluminum rod left over from the LPDA project.

Using a tubing bender, or by hand bend the antenna conductor material in a complete 7 - 8" circle. Now  cut the circle into two equal halves.  Now take a piece of non conductive material, like CPVC TEE which I used and cut it in half and drill two holes. One hole in each side of the tee. flatten your antenna rod half and drill a similiar size hole in that. and fasten with #6 nut and screws. At the top of the loop slip a piece of shink tubing over both ends, but be sure to maintain a air gap of 1/2" between the ends of the loop.
 now you can connect a bnc or sma connector, whichever is needed to connect to your handheld.  Connect the short coax just like a dipole.  center to one side and shield to the other.
 It is that simple to build a bidirectional fox hunting antenna.

The 4 element LDPA

This is a new take on an old design. This author read a article couple of years ago in January 2010 QST magazine about this antenna and the success that author had. I had to build one to see for my self. what I discovered in building this antenna is there are many varying factors that will lead to a success or a failure. Those factors are the type of coax used to feed the antenna, the element spacing and the double boom spacing.

The idea behind the Log periodic Dipole array(LPDA) is very simple. The antenna is driven from the end elements, and the mast. the mast or boom is separated and insulated from each other. Thus. the coax is connected with the center lead to one side and the shield to the other side of the antenna.
This 4 element LPDA being built entirely out of aluminum, is very portable and light weight. it is also very directional and has a high gain.
 The Feed line variable;
You will want to  feed with RG-58 U coax in an odd multiple of 1/4 wave lengths of 2meters. feeding the antenna in this manner it has a broad band coverage of 1.3:1 at 140 MHZ to 1.2:1 at 150 MHZ with a dip of 1:1 at 144 to 146 MHZ. This author discovered that using RG-8U or the mini 8 coax  caused undesirable readings and performance.
Construction ;
the antenna boom is constructed of two (2) pieces of 3/4" aluminum angle cut at a length of 23 1/2".  starting at one end you can mark holes for drilling a 1/4" hole in both angles.  You can clamp both angles back to back to drill.

Hole spacings ;
1)  1" from end
 2)  4"
3)  8"
4)  12"
These are for your antenna radials to mount to.  Now, unclamp your mast and switch it so you can drill through the other half of the angles.  put the undrilled sides back to back.  This will allow you to drill boom spacing mounts and antenna mounting points.
boom Spacing measured from same end as Radial #1 hole.
1)   6"
2)  18"
Okay now your boom is almost complete. You can begin to assemble it.  you will need (8) 1/4"x1/2" bolts, couplers.  These are for your antenna radials to mount two.
For your boom spacing, you will need (2) 1/4" x2" nylon screws and (6) 1/4" nylon nuts.  start with a boom spacing of  1/2". 
For the  eight antenna radials,  you'll need to cut 1/4" aluminum rod into the following lengths.
4) 19 3/4"
3) 17 3/4"
2)  16 1/4"
1) 16"
Now that you have (8) radials cut you need a way to mount them.  on one end of each radial you will need to install 1/4"x20 threads about one inch long.  This will allow enough threads to install locking nuts on each radial.
Feed Line installation.
As discussed earlier in this blog, cut an odd length  multiple of 2m.  Using RG-58U coax.  strip and separate about 4" of the coax.  I recommend soldering on lug rings that will attach under the #4 couplers. Remember, center lead to one side of boom and shield to the other.  I also installed a ferrite core along the coax 6" from the feed point.