The Presidents Page April 2004.

Good Friday afternoon, I wonder how you spent it? Here I am sat at the keyboard writing out this months few thoughts. I know some of you are traveling, some are already settled in caravan parks around the place and some are no doubt busy studying the inside of your eyelids.

In this household since a particular Good Friday afternoon in the late 1970's when perchance a visiting Reverend was called on to assist in helping with adjustments to the plumbing in our home's smallest room, this particular afternoon has on many years since seen me complete with cleaning rods either clearing the septic or drainage systems. But with a new wizbang sewerage system installed last year by our local council this year I expected to be safe from such duties. Except I had forgotten all about the rainwater run off system. So even this dry year there are still little holes and corresponding heaps of dirt in our back yard on Good Friday. Next year will be different, I hope. Time alone will tell.

Our AGM is here again this month, it seems to come around quicker each year. I am pleased to see there are plenty of volunteers for this years committee elections. Our thanks are due to those who have been involved in running the past years events. The committee has met on a monthly basis and we have had plenty of help from others on such event as the Hamfest, JOTA, The Science Show. and our Australia day /Labour Day times away. Thanks again to all involved.

Looking to the future we are now in a firmer position in our desire for a club building. We have the permission of the Guides the grounds committee and the council to go ahead with the sighting of a re-locatable building within the Guides compound. A small sub-committee with Ian VK3BUF will oversee this project. There will need to be working bees to make this into a reality, so, be prepared to help out when needed. We have received news that a grant has been passed to help in the project. Once in place this building will I am sure be a tremendous asset to club activities. Not the least in giving space for kit building, teaching(we still hope for an entry level license scheme) and a shack where we will be able to come and go much more freely than at present. It will give us the opportunity to enter contests as we will have our own entrance to the site.

73s Peter VK3VB.

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An Invitation To Stallholders

On the 17^th of July 2004 the Gippsland Gate Radio & Electronics Club shall be conducting their annual HAMFEST SALE for the sale of new and used electronics and radio equipment As with last year the venue shall be at the Cranbourne Community Hall on the corner of Clarendon and High streets, Cranbourne. (High Street is part of the Sth Gippsland Highway, Melway 133 K4)

Some 40 tables will be available for stall holders, but demand will be very high. Please book early to avoid Disappointment.

Observe the following details regarding bookings:

· Table hire will be $20 per table. Table hire provides access for TWO persons to operate the stall. This will also include two tickets to the door prize and free tea/coffee throughout the day.

· The $20 fee must be paid in full to the Club before the event in order to reserve a table. Cancellations made more than 14 days prior to the event will be given a full refund by cheque.

· To make a booking contact Dianne Jackson on (03) 5625 2545. Or email details to hamfest@ggrec.org.au Payment may be made by sending a cheque or money order (payable to ‘GGREC’) to Post Office Box 1098 Cranbourne 3977 or by direct payment to: BSB 063607 ACC 1015 7247.

· When making a table booking, Stall Holders will be asked to provide a Name, Postal address and Contact phone number.

· Upon recept of the $20 fee and contact details, a Booking Number will be posted with a receipt of payment. IMPORTANT! No booking is confirmed until this number has been received by the Stall Holder.

· Access to the Hall shall be from 8:30am for Stall Holders (not later than 9:30 am unless by arrangement) and 10:00am for buyers.

Last year, the sale was a great success with many hundreds of people through the door in our large Cranbourne Venue, making it a premier event for radio markets in this state.

All proceeds from the sale will contribute to the GGREC fund for the construction of a Club Shack to help promote Amateur Radio in the region.

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Funny Signs

On a Septic Tank Truck in Oregon: “Yesterday's Meals on Wheels “

On a Septic Tank Truck sign: "We're #1 in the #2 business."

Sign over a Gynecologist's Office: "Dr. Jones, at your cervix."

At a Proctologist's door "To expedite your visit please back in."

On a Plumber's truck: "We repair what your husband fixed."

On a Plumber's truck: "Don't sleep with a drip. Call your plumber."

Pizza Shop Slogan: "7 days without pizza makes one weak."

At a Tire Shop in Milwaukee: "Invite us to your next blowout."

At an Optometrist's Office "If you don't see what you're looking for, you've come to the right place."

On a Taxidermist's window: "We really know our stuff."

In a Podiatrist's office: "Time wounds all heels."

On a Fence: "Salesmen welcome! Dog food is expensive."

At a Car Dealership: "The best way to get back on your feet - miss a car payment."

Outside a Muffler Shop: "No appointment necessary. We hear you coming."

In a Veterinarian's waiting room: "Be back in 5 minutes. Sit! Stay!"

At the Electric Company: "We would be delighted if you send in your payment.

In a Restaurant window: "Don't stand there and be hungry, Come on in and get fed up."

In the front yard of a Funeral Home:"Drive carefully. We'll wait"

At a Propane Filling Station, "Thank heaven for little grills."

And don't forget the sign at a Chicago Radiator Shop: "Best place in town to take a leak.

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What Features Of Our Hobby Do You Enjoy?

Accenting the positive about our hobby and our equipment, what do you find personally that lights your fire about our Ham Radio hobby? What equipment features, or new modes, do you find interesting? I started in 1968 and what a world of difference time makes. I have tried to keep current with all the newer modes, digital audio over HF, ALE or remote HF station sites etc.

I have noticed there are a number of hams that are not current, or are new enough not to have been exposed or aware of some of the new interesting developments. This might offer them a clue as to all the various facets of radio they can enjoy or check out.

I will offer up a few that intrigue me as an example.

* I love the new fully menu driven radios like the FT100-D that allow you to optimize and customize your rig, such as EXACTLY setting your mic gain at 17 for AM operation. No inaccurate knobs to collect dust. Or setting up your squelch on SSB different from FM, or being able to modify your transmit offset to make allowances for sharp mic's. The manufacturers that offer complete menu systems give the power back to the user. The less knobs I see the better.

* Having a 100 watt 6 pound rig that you can run off a 12 volt jump start battery so you can go anywhere with it, and enjoy ALL the bands… HF, VHF, and UHF without having to create some monster of a ham station that takes up the whole room of which your wife refuses to dust.

* DSP, good IF type effective noise blankers and outboard MANUAL notch filters that you can place at multiple noise sources to eliminate the snap, crackle and pop or an annoying part of the frequency band of HF in whatever mode. Outboard DSP units with manual notches and tunable DSP like the MFJ 784B are great for this. You can even double up on the DSP's, outboard and internally. DSP of 60 Hz BW is great for CW vs extra 500 KHz filters that are really not needed when using narrow CW DSP.

* Built in microphone equalization, allowing you to adapt to whatever your microphones characteristics.

* I love, through the coax antenna switches, where with the flick of a small switch you can select what antenna is best

* Auto tuners like the FC20 with 100 MEMORIES that are QUIET and that remember what adjustments were made when you were within that band and frequency last time. I notice more auto tuners coming out with more memories like MFJ and others will follow, versus just auto tuners with (no memories) that are fine but fall a step short of quick tune.

* Remote heads off small mobile HF and other rigs that fit in today's smaller car interiors or in the office where you can bring the rig to you and Velcro the head where you want it, versus having to sit in front of the thing in some formal 19th century way.

* The free software allowing us to interface with our laptop computers and a small hardware interface allowing any number of modes and allowing a VX7 with all its memories to be easily controlled without having to enter them manually or to easily manipulate the sequence of frequencies for convenience.

* The narrow bandwidth digital signals that need very little power to reach a destination, from 1 watt to 30 for solid communications.

* I like the frequency stability and accurate readout of today's multi-band rigs, and the AM capability where when you have your rig adjusted right you can fool the boat anchor people into thinking you are talking on a 200-pounder versus a 6 pound multi-band rig and an 8 foot portable loaded dipole.

* Echolink - yes it is ham radio. Where else can you work all countries at the SAME TIME? Having a chat with a mobile in the UK and chatting with a VK down under and 2 or 3 guys from the US… now that's how to communicate. Worked all states and worked all countries has a different meaning when you add the words …at the same time, not just when the propagation is occasionally in. Ham radio can be both, about talking with people direct, via a link, or via a repeater, or it can be via 100% radio, it's about meeting people.

Feel free to add what you find interesting about the ham radio currently, versus the old days and any of my opinions are just that, my opinions only.

73 Rich NJ6F
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When Your Radio Has Saved You

April 1992. I was just 17 years old, since age five playing with radios and electronics in general. I was going from my hometown of Vittoria in Sicily to the Siracuse seaport with my motorbike to get the ferry to reach Malta where I was attending my American high school classes. After 40 km and 15 Km from the first urban center my motorbike just died so voiding my trip to reach the seaport (still 80 Km to go). I was in the middle of valleys and mountain's hills, that time having a mobile phone was something for the richest. I was lucky enough to have with me an old clone of the famous IC 2 2-meter rig (branded as CT-1600).

Time was running out because the ferry that lives Sicily to Malta is twice weekly and could not afford to miss important classes and tests although I was in the middle of nowhere to ask assistance for, so I decided to take out my HT radio to see if somebody could come to rescue (I was not licensed at that time SWLing only), managed to link to the local repeater at 145.600 and after several tries and the disappointment of local hams they finally called my parents so they could send me a rescue tow vehicle and at the same time my cousin to take me to my Ferry.

I felt great that everything went right, that day the radio really saved me from a bad situation and I would ever thank that Sicilian OM to take my distress call despite the fact he could have lost his license.

I would be very interested on reading similar stories how the radio and the operator made THE DIFFERENCE from turning a bad situation to a happy ending.

Enrico Li Perni
IV3SBE northeast Italy
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Operating CW on AM Broadcast Band

The AM broadcast band became an early target as a good place to operate a little CW back in 1956.

As boy scouts, we were learning Morse code and a little electricity, radio, and signaling as we went for those merit badges. The radio badge struck my interest as well as a friend that lived about two blocks away.

His dad was helpful as he had a full workbench with test equipment and of course lots of tubes and old TVs and radios that my friend and I gathered from the trash bins at the two TV shops in the little town of Placentia, Calif. We also took any wire and other useful items from the trash at the electrical contractor and phone company trash.

We learned that a one tube receiver could work better as a regenerative receiver, then we learned from my friends sister that when we turned up the regeneration, she heard us covering up the rock and roll on "color radio" KFWB. Ah, what caused that? My friend's dad explained how it transmitted when this happened.

We were quick to find out more about transmitting and soon had not only good regenerative receivers transmitting, but also good single tube broadband transmitters in the development stages. Not happy that we could not transmit back and forth from our homes yet, we increased the plate voltage and increased our antenna wires at each house. I believe we used 6AG7 tubes, but I may be wrong. The B+ came from the supply of the better AM radios that we had which used a transformer with about 180 volts or so.

Now we were able to hear each other, and nearly on any and all parts of the AM band. To use a phrase from the ARRL - "Now you're talking". No BFO needed, as the signal was rough enough to be easy copy. It was summer vacation and now we settled down to regular skeds many times each day.

This went on for a week or two, but one evening as I sat at the kitchen table having dinner as a family, there was a knock on the door. The front door in that post-war cracker box house was only about 15 feet from the kitchen table, so I could clearly hear the conversation as my dad answered the door to find the neighbor lady from two houses away. She make her point very clear - " I am sick and tired of your kid ruining my listening to the House Party program on KFI, and I want it stopped now!" My dad assured her that he knew nothing of this event, but he would get to the bottom of it.

That was the end to all the fun, and it would be another year or more until I was back on the air, but on 40 meter CW. I might add, that an older kid with a drivers license took us in his car to see how far it went and we did well over 3 miles. To listeners further from my house, they might have mistaken my CW for the CW that would come through many of the AM receivers of the time from a maritime station operating near the frequency of their I.F. strips on 455 kilocycles in Long beach. Cheaper receivers did not have a RF amplifier stage before the conversion stage and KOK maritime would go right through.

Hal, N6TZ@arrl.net
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GGREC Event Queue

Date / Time	Event	Details
Friday 2^nd April	Prac Night
Monday 5^th April	Committee Meeting	John VK3XJW QTH @ 8.00pm
Friday 16^th April	General Meeting	Annual General Meeting
Sunday 18^th April	Hamfest	Midland Amateur Radio Club Inc. Doors open 10.00am, Entry $8.00
Saturday 24^th April	Shack Visit	Mike & Naree QTH. Barby BYO
Saturday 1^st May	Exams
Monday 3^rd May	Committee Meeting	TBA
Friday 7^th May	Prac Night
Friday 21^st May	General Meeting	John Edwards VK3YTV talk about UHF bands
Friday 4^th June	Prac Night
Monday 7^th June	Committee Meeting	TBA
Friday 18^th June	General Meeting	TBA
Saturday 26^th June	Mid Year Dinner	At Guide Hall
Friday 2^nd July	Prac Night
Monday 5^th July	Committee Meeting	TBA
Friday 16^th July	General Meeting	TBA
Saturday 17^th July	GGREC Hamfest	Cranbourne Public Hall, Sth Gippsland Hwy.
Monday 2^nd August	Committee Meeting	TBA
Friday 6^th August	Prac Night
Friday 20^th August	General Meeting	TBA

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My Most Electrically 'Shocking' Moment

It was the snowy winter of 1957. November, I think.

I had saved my high school lunch money for a year, and had just received a superb package of goodies, from Burstein Appebee Company in Kansas City MO. I was going to build a Power Supply, for a future Amateur power amplifier that I was going to build, from a QST magazine article.

I unpacked my new treasures, they included; 1 High voltage transformer 800V - 0 -800V at 250MA, 2 866A Mercury vapor rectifiers, 1 filter choke, a proper bleeder resistor, and several high voltage filter capacitors.

Over the next couple of days, I purchased chassis, tube sockets, terminal strips etc, from my favorite Electronic supply shops, grabbed my trusty Thor electric drill, and built the power supply. I had to build the supply in my bedroom, which was primarily my "workshop" with a place to sleep. It was a nice room, really. Paneled and carpeted, but I had given it the 15 year old kid electronics experimenter atmosphere. My mother sort of tolerated this, in the spirit of learning, self-education, and keeping me busy. She was like that. I remember the dark winter night Mom drove me across town, in a blinding Snow Storm, to a High School Shop Teacher, so I could pass off my Radio and Electronics Merit badge.

Anyway, after I built the Power Supply, with some fear, and trembling hands, I flipped the 866A filament voltage on. In about 2 minutes, the mercury, that had coated the inside of the glass 866A rectifier tubes, had disappeared, leaving clear glass envelopes. The orange filament glow was visible just below the tube plates, in the tops of the tubes.

Trembling, and wanting to plug my ears, in case a filter capacitor exploded, I flipped the Plate switch on, and quickly ducked below the table. No noise, no smoke.

Standing up again, I saw the blue glow of ionized mercury vapor. The Power Supply seemed to be working. The bleeder resistor was getting just a bit warm, and there was a faint hum.

I was very excited to measure the Power Supply output voltage. I grabbed my EICO model 232P Vacuum Tube Voltmeter, and clipped the meter ground lead to the Power Supply chassis. Since the voltmeter was plugged in farther away, the EICO probe would not quite reach to the Power Supply output terminal (a 2 terminal Cinch-Jones barrier strip). With the voltmeter probe in my right hand, I reached over and grabbed the Power Supply chassis, moved it closer to the probe, and touched the well-insulated voltmeter probe, to the Power Supply high voltage terminal.

Time instantly seemed to stand still. I saw the 2 mercury rectifiers light up brighter; my arms were hurting bad, I was shaking, and desperately wanted to move, but my muscles would not let me move. I could feel the current. I then must have blacked out.

I awoke in a strange place. When I could think more clearly, I discovered that I was on the floor, on the far side of my bed, between the bed and the wall (a small space). My chest, back, and hands hurt, and I was having considerable trouble breathing. I managed to get up, and went into the bathroom to observe the damage. I was breathing better now, but my arms were still asleep. I noted, with relief, that I appeared pretty much OK.

Much returned to normal, over the next few days, but I had a large blister on the palms of both hands, for a couple of weeks, and I had upper back pain continuously for several years. I still experience upper back pain. One doctor told me that the back muscles had contracted, and yanked on my spine hard.

Post Thrill Analysis: The EICO 232 Vacuum Voltmeter probe had a setscrew, to keep the coax cable, from backing out of the probe body. In tightening the setscrew, every so often, I had driven the setscrew in through the outer insulation, through the shield braid, through the coax insulation, and it was in contact with

the center (high voltage) coax conductor. My left hand was on the power supply negative (the chassis), and my right hand was on the power supply positive output voltage (through the probe cable set screw). Boy did I ever learn a few things about working around high current, and high voltage!

I do not know if EICO changed the set-screw set-up on the probe, but just be aware, that If you are going to use your classic EICO 232 (a great vacuum tube voltmeter), make sure the set screw is only seated on the probe cable outer insulation, or you too could end up on the floor.

Did I ever tell Mom what happened, while she was at work that fateful day? NO. That would probably have been the end of my brief Electronics building era. If she is somehow now watching me relate this incident, her blue-green eyes would be flashing with the familiar scary sparks, as she prepares to chastise me for never telling her that almost "whacked" myself, back in the winter of 1957.

The Power Supply took it all in stride, and seemed to have no regrets. After the above incident, It was sitting there glowing, and waiting for a much more meaningful load, than me.

My family keeps telling me that "that shock" is why I am like I am. I don't know what that means, and I don't think I want to know Hi Hi.

73 Kent Jarvis (W7DUD)

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Jokes

About 1900, a very respectable western lawyer was filing some insurance

papers when he came to the question: "If your father is dead, state the

cause." Unwilling to reveal that his father had been hanged for cattle

rustling, the lawyer evaded the problem by answering this way: "He died

while taking part in a public ceremony when the platform gave way."

At a medical convention, a noted internist arises to announce that he has

discovered a new miracle antibiotic.

"What's it cure?" asks a member of the audience.

"Nothing we don't already have a drug for," the internist replies.

"Well, what's so miraculous about it?"

"One of the side effects is short-term memory loss. Several of my patients

have paid my bill three or four times."
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FOR SALE

7 COLOR LIGHT PENS

$4.00 EACH WITH BATTERIES

FOR SALE

12V 35-42AH S/H SEALED & WET CELL BATTERIES

$10.00 EACH



50% OF PROCEEDS GO TO CLUB

BUILDING FUND

ORDER FROM REG VK3UK

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Decibels Made Easy (Without Logarithms)
Bruce Spratling, Jr.

Suppose your station has a transmitter that puts out 50 watts of power, a feed line that loses all but 40% of the power, a duplexer that loses half the power, and an antenna that produces enough gain to make the signal 4 times as strong as a dipole antenna. To find the effective radiated power of your station you need to multiply 50 watts times .4 (feed line loss) times .5 (duplexer loss) times 4 (antenna gain) = 40 watts.

Rather than multiply all these factors together, someone decided it would be good to represent them in a way that allows us to add them. An increase of a factor of 10 is defined to be a 10 decibel increase. Decibels are abbreviated dB. Two 10dB increases produces a 20dB increase, because we add decibel increases.

Two increases by a factor of 10 results in an increase of 10 X 10 = 100; therefore 20dB = 100. Three 10dB increases is 30dB, which is 10 X 10 X 10 = 1000.

Because we want to be able to add the dB increases, 0 dB is a factor of 1. Multiplying something by 1 does not change it, just as adding 0 to something results in no change.

Decibels	0	10	20	30
Factor	1	10	100	1000

It’s easy to figure out the meaning of 10, 20, 30, 40... dB, but how about decibels less than 10?

Note that if we multiply 2 by itself 10 times, it generates the following: 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024.

2 times itself 10 times is 1024, which is slightly more than 1000, which is 30dB. 3 added to itself 10 times is 30, and 30dB is a factor of 1000. Therefore, 3dB represents a factor of (approximately) 2.

Another way to derive that 3dB represents a factor of 2 is this: If we add 3dB to itself 3 times we get 9dB, which is less than, but close to, 10dB. If we multiply 2 times itself 3 times we get 2X2X2=8, which is close to, but less than 10. This is good because 9dB should be less than 10 (since 10 dB is 10). We have to multiply 8 by 5/4 to equal 10, and we have to add 1dB to 9dB to equal 10dB. Having 3dB = 2 will work if 1dB = 5/4. Does 1 dB represent a factor of 5/4? If we apply 1dB 3 times, we’ll have 3dB, which = 2. (5/4)X(5/4)X(5/4) = 125/64, which is close to 2. Therefore, a 3dB increase represents a 2 times increase, and 1 dB represents an increase of 1.25.

6dB = 3dB + 3dB. A 3dB increase is a factor of 2, so 6dB = 2 X 2 = 4. Similarly, 9 dB = 2 X 2 X 2 = 8.

So far we have:

Decibels	0	1	2	3	4	5	6	7	8	9	10
Factor	1	1.25		2			4			8	10

Let’s consider negative decibels. -1dB changes 10dB to 9dB, which changes 10 to 8. Therefore, -1 dB is .8, because .8 times 10 = 8.

To find 8dB, think of 8dB as 9dB – 1dB = 8 X .8 = 6.4. To find 5dB, think of 5dB as 6dB - 1dB = 4 times .8 = 3.2. Note that 5dB + 5dB = 10dB = 10. Using 5dB = 3.2: 3.2 X 3.2 = 10.24, which is about 10. To find 2dB, use 2dB = 3dB – 1dB = 2 X .8 = 1.6

Decibels	0	1	2	3	4	5	6	7	8	9	10
Estimated Factor	1	1.25	1.6	2	2.5	3.2	4	5	6.4	8	10
Actual Value	1	1.26	1.58	1.99	2.51	3.16	3.985	5.01	6.31	7.94	10
% Error		.714	-.944	-.236	.475	-.178	-.473	.237	-1.41	-.708	0

You’ll notice from the chart that the results are all within 1.5%.

To summarize the system:

Realize that 3dB = 2, so 6dB = 4, and 9dB = 8.

You know the value for 3, 6, and 9dB (2, 4, 8).

To find 2, 5, or 8dB (1 less than 3dB, 6dB, or 9dB), use -1dB = .8.

If you want to know 4 or 7dB (1 more than 3dB or 6dB), use 1dB = 1.25.

To find fractions of 1dB, realize that 1dB represents a 25% increase, so .1dB is a 2.5% increase, .2dB is a 5% increase, .4dB is a 10% increase. (This interpolation method isn’t exact, but it’s fairly close when dealing with such small values).

You can carry this further for hundredths of a decibel. .01dB is one tenth of .1dB. .1dB is 2.5%, so .01dB is .25%. .04 dB is 1%.

An example: Suppose an antenna has a gain of 17.68 dB. How much increase is this? Note that 17.68 = 10 + 7 + .68. A 10 dB increase is a factor of 10. A 7 dB increase is a factor of 5. Therefore, a 17 dB increase is a factor of 10 X 5 = 50. .6 dB is 15%, .08 dB is 2%, so .68 dB is about 17%. 50 X 1.17 = 58.5, so the antenna increases the signal strength by a factor of 58.5, the signal is 58.5 times as strong (the exact value is 58.61).

Another example: An antenna’s signal is 25 times stronger than a dipole antenna. How many decibels is this? This is actually quite easy. A 10 dB increase is a factor of 10. Because 25 = 10 X 2.5, we still have an increase of 2.5 to account for. An increase of 2.5 is 4 dB, so the total increase = 10 dB + 4 dB = 14 dB (the exact value is 13.98 dB).

Suppose we have an increase of a factor of 30. How many decibels is this? 30 = 10 X 3. To multiply by 10 requires 10dB. But, we need to add the decibels needed to multiply by 3. 4dB is 2.5, but we need 20% more (3 is 20% more than 2.5). 20% is about .8dB, so 30 = 14.8dB (the exact value is 14.77).

Well, that’s my little system for decibels, and as promised, I didn’t mention logarithms!

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