Thursday, April 29, 2010

News from A.R.S. KD8JHJ

Warm weather is finally here and with it the bevy of odd jobs such as lawn mowing and garage cleaning are added to the already lengthy to-do list.  Even with this extra activity I still managed to put in some quality time at the operating position of KD8JHJ.

The Straight Key Century Club's Week End Sprint was held on the 11th of April.  I had a good time making contacts mostly with the Vibroplex bug.  I worked 26 stations in 18 different US states and 2 Canadian provinces.  My ranking was 41st out of 97 entries in the 5-100 watt catagory.  A decent showing for my peanut whistle station I do believe.

This past Tuesday night was the 2 hour Straight Key Sprint.  I worked 10 stations in 9 states and 1 up in Ontario Canada.  For this contest I used my Vibroplex straight key and manually generated all my dits and dahs of Morse Code.  I ended up 33rd out of 56 entries. 

There are two ways to operate a contest.  The method I use mostly is called "search and pounce".  I tune around the band listening for stations calling "CQ CQ SKS" and answer to establish contact.  This method works great for the neophyte cw contester.  You have a chance to make sure you have correctly copied the callsign and other data from the calling station while he works other hams.  When your ready slip your call in after the current QSO wraps up but be quick because there is usually others waiting in line to work the calling station.  The second method is called "running".  Running is simply calling "CQ SKS" and working the stations one by one as they respond to your calls.  Running requires a good strong signal and some skill on the part of the operator.  You want to be able to copy callsigns correctly on the first pass.  Generally keep things moving in an orderly fashion without having to ask for repeats and minimize any errors in your own sending.  On a couple of occasions I have found myself on small runs of three or four stations and it is a thrill to know guys are lining up for a shot at your station.  Running is the key to big scores in contesting.  In order to improve my ability I use a software program called Morse Runner.  This program simulates a CW contest environment.  You are the "Running Station" and the software generates cw stations that answer your calls.  It is very realistic with calls coming at you at different speeds and pitches.  You set the parameters of  speed and level of activity.  In the "Pile Up" mode right after your call several stations answer at once.  Out of this churning soup of CW signals you have to single out one call and work that station.   The program's intended purpose is that of training aid but it is a fun and challenging game too.  You can set the time limit from 1 to 60 minutes and the computer keeps track of your contacts and shows your QSO per hour rate.

The past couple of nights I have noticed that propagation of radio waves on the 30 meter band (10 MHz) has been great.  Last night about 10:00 PM local time I established contact with Jose XE2YWX in Loreto, Mexico about 1670 miles away using the digital mode PSK-31.  Later I called CQ and was promptly answered by IK2WXW Giuseppe in Gallarate, Italy.  This QSO covering 4,361 miles also using PSK-31 and about 25 watts of power.  In between the two DX contacts I met a nice op named Don KB5VP who lives in Vermont.  Don said that after 33 years in the hobby he is still having fun and learning new things.  For example two weeks ago he successfully and for the first time received signals bounced off the moon by hams transmitting from the Aricebo radio telescope in Peurto Rico.  This technique is called EME for Earth-Moon-Earth.  Directional antennas and UHF/ VHF equipment are used for EME work.  Two way communication is possible but it is quite an accomplishment just to receive a radio transmission ricocheted off the Moon.

73 for now from KD8JHJ...

Friday, April 23, 2010

Mountain Bike

I met Isaac at The Mohican State Forest mountain bike trail.  It was late morning, calm with a clear blue sky and a temperature of around 60F.  Trail condition was very dry.  Dusty even.  We rode about 10 miles.  Words cannot describe how much fun this trail is so I will leave it at that.  Here is my vintage chromoly steel Yeti.  Set up as a single speed with 32-19 gears.  Runs like a top.

Tuesday, April 20, 2010

Making Sawdust

  In my basement ham radio station I have two windows.  One window faces west and the other above my operating desk faces north.  I had to come up with a way to display my insulators using the natural light coming in.  The window frames are aluminum and mate right up to the surrounding cement blocks of the foundation.  The only wood is the 2" X 6" sill board that rests on the top course of blocks. Using my table saw I cut up some 1" oak into shelves, sanded them a bit and sealed the wood using Formby's Tung Oil.  I like Formby's because it has a varnish additive and if you want to go crazy you can hand rub layer after layer of this oil to your workpiece and build up a nice glossy finish.  Or in this case I just used a paint brush and slopped it on.  To hang the shelves I used brass eye bolts and hooks screwed into the sill board and measured even lengths of steel chain to support the weight of the load.  On the left are my Hemingray pieces aglow in the setting sun.  The picture on the right is the north facing window.  In the very early morning the sun actually shines on the window for a short time. 

Monday, April 19, 2010

Bike Ride

Bike:  Recumbent
Ride Time:  1:52
Distance:  24.86 miles
Average MPH:  13.2
Max Speed MPH:  24.4

Today the wind direction dictated a ride start heading that put me north-east.  The temperature was 56 degrees F at the beginning of my ride and had dropped to 51 degrees by the stop time.  Skies were sunny but a bit hazy in the country.  The steady breeze was carrying aloft dust from farmer's disking their fields.  This ride was basically a big 25 mile square that took me into the neighboring county.  After 12 miles of mostly flat roads I turned the third corner of the big square and with a following crosswind I was able to kick it up a notch.  On the last leg with the tailwind I was able to hold 20 MPH for a bit.  Even spooked a red tail hawk up out the ditch on the far side of the road.  In a flurry of flapping red and orange feathers he got airborne.  I let off the gas and he flew alongside for short time and then satisfied with me he circled back out of my vision.  Probably heading back to finish dinner.  HP running fine.  Tire pressure was 100psi.

Sunday, April 18, 2010

Springtime Hike at Clear Fork

Today was a typical Ohio spring day in mid April.  The temperatures made it into the 50's so instead of a bike ride my son and I decided on a hike in the woods.  The skies were mostly cloudy with a light breeze from the southwest.  As an afterthought I grabbed my camera and was glad I did.  The first interesting shot I found was this metal sign being slowly absorbed by a Sycamore tree. 

Springtime is a great time to get into the woods.  Temperatures are mild and pleasant with no biting flies or mesquitos yet.  Protected valleys and ravines show the first signs of new life in the forest.  That is Wyatt standing in the skunk cabbage.  The flora changes quickly so I like to get out during early spring and get one last look at the lay of the land before all the understory turns leafy and green and visibility is greatly reduced.
I doubt if any of this woods is old growth forest but due to the ruggedness of the land some of these pockets remain unmolested by human developement and the trees have grown very large.  The country through which we hiked is adjacent to the Clear Fork Reservoir, A man made lake designed and built in 1949 as a fresh water source for the city of Mansfield, Ohio.  Clear Fork is one of only eight Ohio reservoirs stocked with Muskellunge or Muskies as they are known by anglers.  Other fish species in the lake are large mouth bass, white bass, black and white crappie, bluegill and channel catfish.  On land game is plentiful as well.  Whitetail deer and wild turkey are often spotted.  I have seen Osprey and American bald eagles in the area.

Wednesday, April 14, 2010

Isaac's Monocog

Here's a pic of my friend Isaac's Redline Monocog single speed.  He recently built up his own set of wheels which I think is pretty cool.  Isaac comes from a background in Motocross so he is no stranger to two wheeled contraptions and how to work on them.  In the wonderous realm of bicycle maintenance wheel building is the one task I have yet to learn.  That and fabricating my own frame out of metal tubes.

Here's the Specs:  (In his own words.)

Frame and Fork: 2010 Redline Monocog
Wheels: Hope Pro 2 32H (qr front, ss rear), Sun equalizers, Dt swiss champions, Red alum nips.....built by me.....for a grand total of 348 bucks!
Tires: Kenda Nevegals
Brakes: Avid BB7 with jagwire cables, tektro levers.
Seat: Charge spoon, raceface evolve post, hope clamp
Bars: Easton EA50 flat(685mm wide), chunky grips, flipped syncros stem.
Crank: Truvativ five D.
BB: Truvativ square
Chain: Sram PC 870
Cog: Surly
Pedals: Candy X

Nice job Isaac.  You will have a blast on that bike for sure.  I told Isaac I will get my mountain bike out and brush off the cobwebs and we will have to go riding.  I know pathetic- mtb still hanging in the garage with last year's dirt on it but here in springtime we get rain.   I gave up mud riding about 10 years ago.  I try to put in some road miles and cruise the bike paths on my recumbent until the trails dry out enough for knobby fun.

Sunday, April 11, 2010

Insulator Post

Cable Insulator
Secondary Power Distribution
Voltage Rating: 6,600 Volts
Produced 1910-1940
Known as "Mickey Mouse Ears" or just "Mickeys".  The power cable rode in the saddle groove on the top of the insulator.  A Big chunk of glass.  5" tall and weighs 2 pounds.

Thursday, April 8, 2010

The KD8JHJ Bug Tamer

After a product development and testing phase that has lasted 6 months I believe I have finally perfected the KD8JHJ Bug Tamer.  The picture above shows the Vibroplex Original semi-automatic key with the standard moveable weight installed on the pendulum arm.  The pendulum is connected to the lever of the key by a piece of flat spring steel.  When the lever is actuated the pendulum begins a back and forth oscillation.  This movement quickly closes and opens the "dot" contact creating a stream of  Morse Code "dots" which continue until the lever is released.  
One of the myriad of adjustments available to the bug operator is the sliding weight.  Moving the mass further away from the spring slows the oscillation of the pendulum arm while positioning the weight closer to the pivot point speeds up the motion.  By nature of it's design the Vibroplex is a speed key.  It works at code speeds starting around 25 or 30 Words Per Minute and depending on the skill of the operator speeds of 40 and even 50 wpm are possible.  By contrast the traditional straight key familiar to most as seen in movies and tv produces speeds ranging from 5 wpm to 20 wpm or a little faster if the operator is highly skilled.  In years past the Vibroplex shipped with a weight half the size of the standard weight shown above.  In the early days a Vibroplex typically cost a telegrapher a couple weeks worth of wages so by the time an operator could afford to upgrade he was already proficient at copying high speed code.  In my case even after one year of using Morse Code my copy speed was not up to even the slowest speeds of the Vibroplex.  Because of my desire to use this key on the air for amateur radio at my comfort level of 18 to 20 wpm I would have to either buy or build a means of slowing the pendulum action of my key.
There are commercially made devices available to slow down the dot stream but I thought this would be a great opportunity to exercise the old ham tradition of  "build it yourself" or homebrewing as it is known.  I studied all the pictures I could find on the internet of different designs both commercial and homebrew.  I settled on a design based on the parts I could find at the local hardware store.  The final revision of the KD8JHJ Bug Tamer is shown below positioned to yield sending of about 20 wpm.

The silver weights are steel shaft collars with a set screw that locks down the collar in place.  I found a piece of brass tubing that fit over the round steel pendulum arm.  The locking collars in turn slide onto the diameter of the brass tube and are held in place by their set screws.  Hidden from view is a short piece of solid brass rod about 5/8" long that fills the empty end of the tube that extends out past the end of the steel pendulum arm.  (The brass rod is positioned under the three weights.)
During the testing phase I experimented with different tube lengths and number of locking collars to add more weight and to get an idea of how the placement of mass affected the performance of the key.  My initial version was set up with all the weights at the end of the tube farthest away from the pivot.  During the course of a QSO the whole assembly would slowly creep outwards letting the mass move furthur and further from the spring, slowing down the characters.  To fix this problem I positioned one of the locking collars at the inside end of the brass tube.  Snugging the set screw prevented the slow creep during use yet remaining loose enough to allow the bug tamer to be moved in and out to adjust the dot speed.
Not only does the position of the mass affect the action of the pendulum but the amount of weight also contributes to the smoothness or lack thereof in the keys operation.  Through my experimentation I was able to get an idea of the parameters of weight and placement of the mass to come up with a design that slowed the action of the key while still providing crisp closing of the electrical contact.  If the mass is too far out past the damper assembly it causes the key to feel "clunky" and makes it more difficult to make accurate transitions between the dashes and dots of the code characters.  In some of my earlier pictures only two weights were positioned at the end of the brass tube and the whole bug tamer would be extended out further.  This did provide crisp feel but the dots seemed softer or "mushy".  Adding another weight and running the bug tamer closer in to the pivot point let the contact close with more authority and seems to produce the nicest sounding dots. 
The Vibroplex is a wonderful mechanism and makes a great test bed for tinkering if one is so inclined.  I believe that this exercise has helped me to better understand the intricate workings of the semi-automatic key.  After 6 months using the key on the air I have become confident in my sending with the bug and have received several compliments on my good bug fist.  I truly believe that in order to be a good bug op one has to have a solid understanding of the mechanics of the bug key.  The only way to gain this understanding is to spend time playing with the various adjustments and observing how these changes interact with the operation of the key.  From time to time I do put the original weight back on and do some practice sending but still find it a bit too fast for accurate sending.  As a rule a ham should send out a call at a speed he or she can easily copy as the op who answers the call will usually do so at the same speed.   

Thursday, April 1, 2010

KD8JHJ 1st 40 meter QRP/portable Operation

This first portable outing was really more of an antenna test than anything.  About a month ago I had purchased a Radio Wavz 20 meter End Fed Half Wave antenna with the intention of putting it up at the home QTH.  Upon my initial inspection of this antenna I noticed that although the Radio Wavz sticker on the matching unit said "20 meter" someone had taken a sharpie and wrote "40m" on the cylindrical body of the matching unit.  I put it up anyway on the tower and proceded to check it out with the MFJ-259B antenna analyzer.  To my dismay the best Standing Wave Ratio I could find was 8:1 and no where near the 20 meter band.  I took it down and replaced it with the 30 meter EFHW described in an earlier post.  The antenna sat coiled on the floor of the shack until today when I measured off 67 feet of AWG #12 copper wire that I had left over from a electrical project at my shop.  I soldered on a ring terminal and attached it to the 20 meter matching unit.  I fashioned a couple insulators from 1/4" Lexan polycarbonate for each end of the antenna wire. 
I packaged up my MFJ QRP transceiver and test equipment into a 5 gallon bucket and hopped in the car for the short trip south of town to the public park near our town's fresh water reservoir.  This area has lots of open spaces and trees- perfect.  I tied some string to a 1/2" bolt and on my very first try launched the line high into the bare branches of a tree.  I tied the string to the end of the antenna insulator and pulled it up.  the other end with the matching unit I fixed to a post near my car so that the feed point was about 10 feet off the ground.  For connection to the rig I used a 50' piece of coax. The end result was roughly a 40 degree slope of antenna wire.  I used an online antenna length calculator to figure how long of a piece of wire to cut.  7.060 MHz showed a length of 66.2 feet so I cut the wire at 67 feet and figured I could trim it down once I had it in the air and got a measurement with the analyzer.  As expected with the wire a bit long the resonant point was 6.990 MHz with a SWR of 1.1: 1  This also confirmed the screw up at Radio Wavz with the 40 meter matching unit being miss labeled a 20 meter unit.  I suspect as often happens the antenna was returned as defective and sent back out upon the next order.  Not a big deal because I needed a 40 meter unit anyway for my single band transceiver. 
My plans were to trim the antenna to resonance around 7.060 MHz but of course I forgot the wire cutters.  I decided to let it be for now and give it go.   As I had hoped reception away from town was great and I could here many signals loud and clear.  I called QRL? and sent some CQ's at a few places between 7.030 and 7.060 MHz with no response.  Finally around 7.040 MHz somebody responded with "KD8??".  I sent my call again slowly and then on the second repeat I noticed that my battery pack had reached the low voltage point and could no longer provide the required juice.  I think I then copied something from the other op about my signal dropping off. 
Unfortunately activity was cut short just as things were getting underway.  Overall I came home happy with the experience.  It was fun to select a site and deploy the wire.  Getting the end of the wire up high was no trouble at all.  The best part of all was being outside on a warm spring day.  I can tell already that portable/qrp operations is something I will be doing alot of this summer.  Letting down the antenna and packing up the gear was even quicker than the setup.  This weekend I plan to get out again and if I can remember the wire cutters I will trim the wire down to get the resonant point to the middle of the CW band maximizing the effectiveness of my 5 watts.