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Messages - K9DJT

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1
General Discussion / Re: Unreal radio collection
« on: February 23, 2016, 08:38:39 PM »
There had been an article in QST a few years ago about George and his collection.  He attends the W9DXCC convention every year and I've had the honor of sharing a table with him at the banquet a couple of times.  He is also active on some of the regional nets.  I believe Chuck, W9KR, has spoke with him on the air several times.  As a matter of fact, George is looking for someone who might take ownership of the collection and create some type of museum if you well.

73, Gary
K9DJT

2
General Discussion / Re: Two transmitters, one antenna
« on: February 23, 2016, 08:24:20 PM »
You do NOT want to use a "T" between the radios.  Good possibility of damaging one of the receivers.  A switch is a good alternative or a "coupler" which could be placed outside if within some type of housing. You can couple two antennas to one radio or two radios to one antenna. You'll need to check the specifications regarding bandwidth, power rating and Db of separation.  DX Engineering is one of many distributors who offer them.

73, Gary
K9DJT

3
Wanted / Re: Antenna ID required x3
« on: September 09, 2015, 10:10:59 AM »
Hi Kevin,

As Tom, W9IPR, said on the ORC mailer; it appears to be a TV antenna on the top.  The vertical could be almost anything.  Unable to tell without some type of model number which could be Googled.

Regarding the tower itself.  It appears to be a Rohn 25G.  I have two of them at my QTH and have climbed several.  My understanding of the Rohn spec's is that it is a free standing tower at 30 feet with one yard of concrete at the base.  Also stated as 30 feet above a house bracket.  My understanding of your statement is that you have 40 feet plus the 9 foot top section.  If your house bracket is at 9 feet, that means you have 40 feet above the bracket.  With the small array on top as pictured, it has and most likely will stayed up.  I wouldn't want to put a tri-bander and/or additional wind loads on it without removing a 10 foot section.

As a side note, I would expect this posting in the antenna section of the forum rather than the "Wanted."  My thought is you'll receive more comments if you move it there.

Look forward to seeing you at the meeting tonight.

73, Gary
K9DJT



4
DXing / Re: New to understanding HF bands
« on: August 11, 2014, 08:38:53 PM »
Hi Kevin,

The are openings on 10M and even on 6M. Keep checking the cluster.  160M is primarily a night time band...and best during winter.  You'll find some nets and a lot of rag chewing on 160M.  Same goes for 80M...good at night with even some SSB DX at 3.7Mhz and up.  Call CQ above 3.6Mhz.  Also DX on CW at the bottom of the band just above 3.5Mhz. A lot of nets on 75M above 3.9 MHz late after noon.  Again, band best during the winter months.

Hope this is of help.

73, Gary
K9DJT

5
Test Equipment / Electrical Safety
« on: July 17, 2014, 09:36:20 AM »
This is my 12th installment of “Understanding Test Equipment” and it just dawned on me I hadn’t addressed anything relating to Electrical Safety.  I am ashamed because it should have been one of the first things, and something none of us shouldn’t take lightly no matter how much experience one may have.

Did you know there is actually a correct way to connect and disconnect a piece of test equipment to a unit under test (UUT)?  Especially if you are using leads with alligator clips on them.  The correct way is to connect the low side of the test equipment, i.e., the ground lead (negative) to the UUT ground first, and then connect the high side, i.e., the positive lead to the potential (voltage).  When you disconnect from the UUT you just reverse the process.  Disconnect the positive first and then the negative.  So what difference does it make?  If the UUT is already powered up, it makes a big difference.  Let’s take a look at why.  During my travels, I had met an electrician who was working on a motor-drive system and disconnected the negative lead first and let it drop.  He created a lot of unnecessary damage in doing so because the negative was in reality “HOT”, i.e., it was at the same potential (voltage) as the positive lead of the test instrument.  The SCR’s the lead struck on the way down were not happy.  Remember the meter or scope you are using has an internal impedance (resistance), which no matter how large, has the same voltage at both ends until the negative side of that instrument is connected to the negative side of the voltage you’re measuring.  Let’s say you didn’t have an insulated boot around the negative alligator clip (dumb).  You grab it and remove it from the chassis and you are now holding onto the voltage you were measuring.  And yes, you might be unwilling holding it.

During my early years in electronics, age 12 to 20, it wasn’t uncommon to see many cartoons of some character being electrocuted and supposedly unable to let go of the wires.  It was always common to hear that we should work with one hand behind your back, which is still a very good practice, and stand on a rubber mat, which is also a good thing to do.  Well, of course I didn’t believe in this stuff.  I had already had so many shocks working on five tube radios and TV’s and was always able to pull away.  What nonsense I thought.  Well, it caught up to me while attending MATC.  My lab partner and I were setting up an experiment and all the stuff we were using was bread boarded.  The mature (older) hams will remember transformers, inductors, potentiometers, resistors and capacitors mounted on wooded boards with their leads to some type of spring connector which you pushed down and slid a wire trough.  It turns out my lab partner, who’s name I still remember and called on as a customer at GE Medical, had taken a power transformer, which had a line cord permanently attached to the primary, and plugged it in…WITH NOTHING CONNECTED TO THE SECONDARY!!!  No one would do anything like that.  Right?  Being fearless as I was, I proceeded to set up the circuit without ensuring the transformer was dead…and in doing so had a pair of fingers of one hand holding one end of the secondary while only one finger of the other hand just touching the terminal of the other end of the secondary.  400VAC hand-to-hand!  Unable to let go…unable to speak…everything going dark.  The momentary passing out is what save me as I fell off the lab stool.  I still remember the helpless feeling when trying to talk and all the other students laughing at me while thinking I was pretending and acting silly.  The above is a long story to make the point of; never trust anyone else regarding a circuit being dead or disconnected!  An example being a coworker or friend who may say, “I turned the breaker off.”  Don’t believe them…test all dead circuits yourself to ensure they are in fact dead.  How do should we test for a dead circuit?  No matter what you use, a VOM, DMM or Volt-Alert wand device, always test the instrument first on a known live circuit first.  This lets you know it is in fact working,  Then test the circuit which you believe to be dead.  Assuming it is dead by showing a zero voltage/potential, take the instrument back to the know live source again and ensure it is still working.  In this way you know the measuring device is working before, during and after the test of the dead circuit.  This is most important when using an instrument having test leads which may become intermittent.

I met many many people during my years as a sales engineer who experienced many close calls or knew someone who wasn’t as lucky as I.  The thing is, I never met a dumb electrician…all the dumb ones are dead!  Safety, relating to anything, is being smart and aware of your surroundings.  THINK about what you are doing!!!

Be safe out there!

73, Gary
K9DJT

6
General Discussion / Re: Time Lapse Video From Field Day 2014
« on: July 02, 2014, 11:03:40 AM »
LeFrog does their FD on the bluff in Port Washington.  And ORC does theirs in Washington County.  Go figure!   :D

Very nice job on the video Bob.  I'm hoping Brian and figure a way to make it available on our web site.  We all know he has nothing better to do!   ;)

73, Gary
K9DJT

7
General Discussion / Re: Baofeng UV-82X HT links
« on: July 02, 2014, 10:01:30 AM »
Had great success with the CHIRP software.  Turned out the cable I have for my Kenwood TH-G71 also works with the UV-82X.  Went on to program all the 220 machines between here and my cabin along with a few simplex frequencies.  Then programed several VHF machines, simplex frequencies and all the NOAA weather channels.  The upload to the UV-82X was flawless.

The caveat I came across though, was when I turned on the Baofeng it remained in the "Frequency" mode and I couldn't figure out how to see the "Memory" channels I just programed.  There was nothing in the menu which allowed me to switch.  So, I started to depress buttons while turning the power on and had success.  With that being said, the following is what needs to be done to toggle from the "Frequency" mode to "Channel/Memory" mode and back:  "TURN OFF THE UV-82X, HOLD THE MENU BUTTON DOWN WHILE TURNING THE RADIO BACK ON." Everything you programed should be there.  If you want to revert back, just repeat the process.

The second caveat I came across was with the software where you're able to open up files like the "Repeater Book" predefined channels and wanting to dump them into the radio.  (At this point you should have already created a new file to program the channels.)  This is what needs to be done:  "OPEN THE FILE FROM THE REPEATER BOOK, e.g., OZAUKEE COUNTY REPEATERS, AND GOTO FILE, CHOOSE EXPORT, AND SAVE SOMEWHERE AS A .CSV FILE.  NOW GO TO THE NEW FILE YOU CREATED TO PROGRAM THE RADIO, AND IMPORT THE CSV FILE INTO THAT."  It should it work.  At this point you are able to insert blank lines above and below entries and you are also able to move entries up and down within your list.

Please find the attachment of the what I created for my radio.  You should be able to import it into yours!

Hope you find this of help.

73, Gary
K9DJT

8
General Discussion / Re: Baofeng UV-82X HT links
« on: June 26, 2014, 09:34:05 AM »
I really want to thank Tom for providing the links.  I don't have a programing cable yet, so at this point I found the first miklor.com link he posted to be the most helpful.  It provides the main stuff we'd be looking for in a manual...unlike the one which comes with the radio.

Had a QSO with N9LAD and K9QLP this morning on 220 Mhz and received good reports.

73, Gary

9
General Discussion / Re: Baofeng UV-82X HT links
« on: June 25, 2014, 08:04:21 PM »
Just received mine today.  Set it up on 220 but was not sure on the negative offset. As Tom posted, it's 1.6 MHz! Thank you to Jerry for replying on 97. Had trouble believing it was that large. Anyway, I was able to pull the machine up.

73, Gary
K9DJT


73, Gary

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10
Swag (Hats/Jackets) / Re: New Items Available!!!
« on: June 07, 2014, 06:03:49 AM »
Hi Tom,

The polo is a 60% cotton/40% polyester blend. The wind shirt is 100% polyester.  No wool! ;-)


73, Gary

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11
Test Equipment / Ohmmeter and Insulation Testing
« on: June 06, 2014, 11:23:47 AM »
Last month I presented the idea of diagnosing electrical problems by measuring, or should I say looking for voltage drops in unlikely places, e.g., simple components such switches, connectors, lugs, terminals and wires.  One might ask why I wouldn’t recommend using the ohmmeter in the DMM (Digital Multimeter).  The main reason is that a higher energy component, whatever it might be, is not being stressed by the ohmmeter in contrast to being under a full load or operational stress.  So when would I use an ohmmeter?  I only use it for very simple, extremely low voltage and/or signal carrying connections.  The best example I can think of would be a mic cable, connector combination.  Basically from one pin or wire to the other end of the wire/connector.  When doing so, I would normally use alligator clips on the test leads so I am able to use both hands and flex the cable at both ends while looking for an intermittent open or short.  It’s a great measurement for such things.  Could I use it to measure the contact resistance of a relay?  Yup!  It would be perfect for antenna relay…you’re not going to look for a voltage there as you might on a DC circuit.  What you need to remember though, is to take the test lead resistance in consideration with the measurement.  A good set of test leads when shorted together should read anywhere from .1 to .5 ohms max.  You can mentally subtract that from your test measurement, or use the “Delta” feature I explained in a previous article, which will cause the meter to display the difference of the first measurement to the second.
OK, let’s say you want to check a transformer or choke in that old radio you just bought at Dayton before turning it on.  It isn’t that you don’t appreciate the adrenaline rush with a smoking transformer, but prefer not stinking up the whole house with the smell.  What you really want to do is measure the resistance of the insulation of the wire used in the transformer.  So, is this a place to use the ohmmeter?  Yes and No…meaning you would be able to detect a direct short to the transformer housing…maybe.  Think of what type of stress a standard ohmmeter places on that winding.  If it isn’t an old analog Simpson, it’s less than a volt and a half.  Do you think that is even close enough to detecting a failure in a questionable winding?   You’re right, it isn’t!  We need to stress this thing with some real voltage to see if the insulation has any leakage or will actually break down.  Hence, the “Insulation Tester” which is aka “Megger”.  Basically, an Insulation Tester is an ohmmeter which uses a very large voltage, i.e., up to 5,000 VDC, but a low current which is limited to about 2 mA.  It has selectable  voltage ranges and will detect leakage between windings and/or the housing.  The display reading is typically in the meg ohm range.  You normally will test a winding at twice its operating voltage, e.g., 480 VAC would be tested at 1000 VDC and a good winding would be 1000 ohms per volt.  In this case, 1000V X 1000 ohms = 1 meg ohm or greater.  Any value less than 1 meg would be considered a questionable device.  I just presented the very basic test.  We can make it more complicated in a future article!

See you on the radio!

73, Gary
K9DJT


12
Swag (Hats/Jackets) / Re: New Items Available!!!
« on: June 06, 2014, 11:17:05 AM »
I managed to get a little better pricing on the new items.  The polo cost is $24 and the wind is $30.  Both of the items I am wearing in the pictures are XL, and I feel the wind shirt is running just a hair smaller than I would like, so you might want to order it one size up.

Hope you like them!

73, Gary
K9DJT

13
DXing / Re: Who does DX?
« on: June 03, 2014, 08:02:13 AM »
Hi Kevin,

Are you familiar with the DX Clusters available on the internet. If not, you need to check them out.  This is only one of many:  http://www.dxwatch.com/dxsd1/dxsd1.php?f=603

73, Gary


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14
Wanted / Re: Wanted: HF rig and tuner
« on: June 03, 2014, 07:51:19 AM »
Hi Kevin,

I have an FT-450 which is in excellent condition except that the antenna tuner no longer works. The tuner could be repaired, or my other consideration would be purchasing a LDG-450 (I think that is the model) which would have a broader tuning range. There is a picture of the radio on my QRZ page cabin location.

73, Gary


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15
Can you draw some kind of sketch of what you have?


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