Finished My RF Safety Report

Had a really nice one about 90% finished that I'd been working on for three days.

Then I was editing a section of it this morning (no coffee!), and I NUKED the whole damn document..............RATS!

Just finished a frantic 6 hour push to get at least something presentable printed out.

The question of RF Safety on the Iowa is something that's a bit overblown, as getting to the Disc/Cage antenna on the bow means going through a locked gate that only authorized people have the key for. The public can't get within 50 feet of it.

The Trussed Monopole antenna at the stern is located on top of the Helo Ops shack, and is a good 10' above the deck.

Assuming ZERO feedline loss (we don't have a clue what the line loss is, but I'll bet it's at least 2~3dB), the fact that we run *maybe* 100 Watts out of the transmitter, and the fact that the Duty Factor for SSB is 20%, and CW is 40%, the minimum safe distance for the "Uncontrolled Area" (where the public is allowed) is FIVE feet.

There's just no way we're pumping out enough RF to do anything to anybody.

Got Those "Term Paper" Blues......

Well, not exactly a "Term Paper", but it makes me glad I wrote all of them in high-school and College.

I've been asked to do a short report on RF Safety, and how it pertains to the Amateur Radio operations aboard the Iowa.

Actually, I was asked to do a full report, and oh, by the way, can you have a short one available for our meeting this Wednesday?

Now, all the Hams I know are quite conversant on RF Safety, and we've all performed our FCC mandated RF Evaluations of our stations.

I don't know a single Ham who has not done this, and nobody I know has a station that doesn't meet the requirements.

The "problem" arises when you say "RADIATION" around most lay people, who don't know the difference between an X-ray, cosmic ray, a sun ray, or even a "Ray of Hope". All you have to do is mention "RADIATION", and people start thinking of giant ants, giant grasshoppers, or Big Things We Accidentally Created/Let Loose/Got Pissed Off.

Since Radio Frequency radiation is NON-Ionizing, it's extremely unlikely to cause gigantic tomatoes and bugs to start appearing under your antenna. It just doesn't work that way.

The primary harm the high levels of RF can cause, are thermal hazards, similar to sticking something into your microwave oven and cranking it up.

And even that has requirements to be met before the object will heat up.

It's true that in the "Olde Days" Diathermy used a frequency in the vicinity of 30 MHz, but the patient was positioned in almost direct contact with the antenna, and the antenna was designed to concentrate the RF field into a very small area.

They weren't having people stand under a half-wave dipole and applying 100 Watts to it.

So, I'm writing this with the LCD principle, trying to make it simple so non-technical people can understand it, while keeping it technically accurate, and not boring the people that actually understand it.

I just hope it doesn't get picked apart by the people who are "just too busy" to take this task on themselves, but yet not so busy that can find the time to read it, and nit-pick it to death.....

More Rain on the Way

We probably won't get as much as Wirecutter will, but still, they're predicting at least an inch, and probably more.

The bad thing is that this time we're going to get it all in about 24~36 hours.

Hopefully the backyard won't flood too bad, as all the dirt is still wet from the last rain that came through.

And for an AAR on Saturday's "NRA First Steps" class, it was another winner.

We had 22 students, the max the classroom can hold, and 4 assistant instructors.

The lead instructor handled the three people who had prior experience with firearms, but wanted to get some training, and the rest of us handled the 'balanceof the students.

Everybody listened, was safe, and we saw some students go from Can't hit the paper", to scoring 80% or better on the last 10 rounds on target session.

Another great day ay the range!

December 7th, 2014 on the Battleship Iowa

Spent all day on the Battleship Iowa today, mostly in the radio room working HUGE pile-ups calling us.

Everybody we talked to thanked us for getting and keeping the Iowa on the Ham Bands, and manning it so often.

We operate NI6BB every holiday, except Thanksgiving and Christmas day when the ship is closed, and almost every Wednesday, during the hours the ship is open.

We talked to the Missouri, the Lexington, the Hornet, the Midway, several of the museum submarines, and heard the Wisconsin, but couldn’t get through to them.

We had an elderly man at the morning ceremony who is a Pearl Harbor Survivor, and a wonderful gentleman.

Later in the day I was honored to meet and talk to a 93 year old woman who was a nurse on a hospital ship stationed at Pearl during the raid.
 
And they both told everybody they met to never forget what can happen to Our Nation when it gets complacent.

Quite a somber day.

Busy Weekend Coming Up

Well, let's see....

Saturday morning I have the "First Saturday Of The Month" breakfast with the radio club I'll be bailing out on (long rant, check the older posts), and then I'll be helping with another "NRA First Steps" pistol class, then a reunion party for a bunch of my former work mates from the satellite launch place I retired/got laid-off from, and then I'll be on the Iowa all day Sunday for the Pearl Harbor Memorial.

I'll be wearing one of my "NRA Certified Instructor" shirts to the breakfast, which will probably pop the fuses in the one Ultra-Liberal, Politically Correct member we have.

Oh, well.....no use trying to please everyone.

Rainy Day on the Iowa

Spent today aboard doing Grey Radio stuff, mostly reading the manuals, as yours truly has been "appointed" as the Lead Technician to get the original transmitters fired back up.

So, after helping the 70 and 80 year old guys go down to Broadway in search of some replacement parts for one of the "Red Phones", I spent some reading the manuals on the exciter, power amplifier, and the auto-couplers.

I learned that the exciter only puts out around 100 mW (+20dBm), and the high voltage in the power amp is 2250 Volts.

The amps are capable of running up to 1500 Watts output, but the manual cautions to not go over 1250 Watts, which is a kick because EACH of the power tubes is rated for about 5kW plate dissipation!

Man, talk about OVER designed!

And then I helped the Old Guys (I'm a youngster there!) work on the "Coke Machine", which is this beautifully built rack of equipment (Hughes Aircraft in Irvine, CA built it) that basically a switching matrix to route secure and non-secure communications around the ship.

I ponied up for a big 24VDC power supply so they could get parts of it working, but ALL of the circuit cards were pulled from it while it was in the Mothball Fleet, as it's a system still in use.

None of it's classified, and we're having a hard time finding stuff for it.

Anybody have any "1149570 TIM Manual Patch Cards", or "1149565 LIM Manual Patch Card" spares just sitting around?

Sure would make it easier to set up the manual patches we need to make so we can route audio from the "Red Phones" to and from the Radio Room and Transmitter Room.......

A Little Rainy Day Music

By Bachman Turner Overdrive.

This is one of their lesser know songs.

Has some really nice guitar work.

Enjoy!

Rain!

And boy, we need it!

It started raining about 0500 this morning, and is supposed to keep up through Wednesday morning.

So far it's been a nice, steady rain, with the rain gauge showing .39" since this storm began, but it's starting to pool in all the low spots in the backyard, and the scanner has a lot of traffic about road closures due to flooding.

No word on any mud slides, though.

And the dog, who doesn't like to go out in the rain, is in "Max Bladder Hold Mode" right now. She'll go scratch at the door, I'll open it, and she sticks her head out the door, looks up at me, and heads back in the house.

As soon as it beaks a bit, I'll grab her and get her to go out, whether she likes it or not.

AND, we're up to .93" since midnight, which is quite a bit for us to get all at once.

Visio 2010 Is A MAJOR PITA!!

God, I can't believe how freaking AWFUL this software is.

I've been using Visio for over 10 years, I've mad over 100 drawings with it, and it seems like every single time I stop using it for a few weeks, I have to learn it all over again.

Even doing something simple like changing the default line weight is cumbersome, and the changes you make don't carry over to the individual stencils/shapes stored in your library.

The earlier versions at least had the menus laid out in a logical manner, but nooooo, that wasn't good enough for Micro$oft, and they changed everything around, and I can't find sh1t in their newer structure.

IfI have to bang my head against the keyboard until Its bloody learning this POS software again, I'll just take the time to learn one of the Linux vector drawing programs I have, as they don't change things around on a whim.

Either that or I'll just make the damn drawings by hand, scan them, and convert them to a pdf for distribution.

Gawd.......what a pain this little project has become!

UPDATE

Did the entire project in about 35 minutes using "gschem" on my Linux box, and I'd never used the program before.

It reminds me a lot of the free software (Windoze only) that PCBExpress gives you to do your boards.

Since this will be hand-wired, and I don't need boards produced, I just wanted a nice looking schematic to go into the operating manual.

The project is an interface board from a sound card on a PC to a Kenwood HF radio so we can do "Digital Modes" on the Iowa.

Here's a copy of the schematic, but it didn't render very cleanly when I did a quickie rendering from PostScript to PNG format.

Rain On The Way....YAY!

Heavy overcast this morning, and I can smell rain on the wind.

NOAA forecast is for scattered showers today and tonight, haevy rain starting Monday night through Wednesday morning.

We sure need the rain, and hopefully we'll have a wet winter.

It's been extremely dry out here the last 5 years or so, and the reservoirs are down to their lowest levels in 20 years.

This afternoon's satellite view:

Happy Thanksgiving

Hope you all have a very Happy Thanksgiving!