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Showing posts from August, 2015

Building a new beam antenna installation at N6QW ~ Part 11

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More Preparations for the Rotor and Mast Installation Since this is Part 11 you can well see that I have abandoned Roman Numerals and counting in Latin. Too bad Miss Bushnell! This is the third day since the concrete was placed (not poured) and so it is OK now to remove the forms (yes I waited only one day). The three days is to allow the concrete to set enough to proceed with the follow on work. I can say this is not the best placing of concrete I have done but it is "good enough" for this install. The first thing I wanted to do was a "fit check" of the rotor assembly. This is where you get that sinking feeling that the anchor bolts are in the wrong place or may have shifted during the concrete placement. Well I am happy to report that the rotor plate assembly fits on the anchor bolts and you can see that below. I wear a size 10 shoe and you can see that as a reference point in the photo. (So OK I could have cropped the photo and my shoe would disappear but this d…

Building a new Antenna at N6QW ~ Part 10

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Placing the Concrete Base We are victims of our past experience! Upon graduation from college (BSEE) I had to serve four years in the US Navy Civil Engineer Corps. That scholarship from the US Navy entailed a large payback -- four years of my life. During that four years I got to operate as DX from Midway Island (then KM6) but unfortunately no operation from South Vietnam during my two trips there. As with all industries, workplaces or even the military there is certain acceptable and respected common language. Much of the construction  work of the "Seabees" involved concrete, and the proper terminology was "placing concrete" not "pouring concrete". The real subtle difference was that placing had an air of precision whereas pouring sounded like a "random spilling out" that literally went everywhere. So for my project, obviously involving precision and the "knack", I placed the hand mixed concrete into the homebrew form. Don't get…

New Beam Antenna at N6QW ~ Part 9b.1

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Building the Concrete Form for the Base Mounted Rotator ~ Updated 2X Today we will cover the construction of the temporary wooden structure that will provide the form for the concrete base. Our initial calculation was that the reinforced concrete base would be about one foot cube with a portion above ground and the remainder below grade. While that seems sufficient there are other critical dimensions which include the actual area of the top surface. The US Tower base mounting plate is essentially triangular since it is intended to be mounted within a triangular steel tower. My selection of the RP-3 (the smallest) is identified as "fitting" within a 10 inch top section thus we have approximate dimensions, likely the triangle altitude (known a "h")  being close to 10 inches --well it is something less than that. The baseplate assembly, L brackets and anchor bolts are shown below, and were described in 9a. At times it is the "practical" that drives the final…

A Trip Down Memory Lane -- N6QW's first experiece with Solid State Devices

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Case Zero -- How it Started On August 23rd, 2015 I had cause to do an Internet Search on one of the most popular electronics magazines that started in October 1954. Oddly enough it was called Popular Electronics. In that issue I spotted an advertisement for one of the very early transistors that was available to electronic enthusiasts. Enter the Raytheon CK722 and you can see a snip of the ad below. Actually I had been using a CK722 prior to this ad --I must have been about 11 or 12 years old at the time and my use was as an audio amplifier for one of my crystal sets. Here you see the ad for building an electronic timer. Imagine what you could do with a solid state timer back in 1954. Keep in mind the scientists at Bell Labs had invented the transistor a scant six years earlier. From a lab to the consumer in such a short period of time was simply amazing in 1950! Think about it -- there had to be a wholesale development of manufacturing techniques to mass produce transistors. Buildi…

New Antenna at N6QW ~ Part 9a Contiuned

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Photos of the RP-3 Base Plate, L Brackets and Anchor Bolts* Current Antenna Moved ~ Staying on the Air During Construction
Work began in earnest today on assembling some of the major support structures. The use of Simpson Products L Brackets has greatly facilitated the build. The brackets come pre-drilled and one of the holes aligns perfectly with the RP-3 base. An opposite hole is enlarged to 1/2 inch to accommodate the anchor bolts. This was easily done on my Sears pedestal mounted drill press. About 20 Minutes of total work. The hole size in the RP-3 and the Simpson L Bracket is 1/4 inch so no additional drilling required there. Just for grins --with shipping the RP-3 cost nearly $100. The L Brackets and Bolts were cheap --about $12 with the Stainless Steel bolts and nuts for the RP-3 Plate to bracket assembly.

August 21 ~ Moved the current antenna about 3 feet to open an area for construction of the new concrete base. This area will be suitable for this antenna in the permanent s…

A new beam antenna build at N6QW ~ Part 9

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Project Update I have become great friends with the local UPS delivery man assigned to my route. He keeps dropping off packages and religiously inquires about the status of my beam antenna project. So the blog readers I am sure would also like to know the current status. Essentially the rotor mechanism will be located at the base and the entire mast and beam will rotate. The Configuration  Diagrammatically the antenna installation will look like the sketch below:  Starting with the base which will be 1 foot cube of reinforced concrete using rebar this will provide a platform to anchor the rotator and vertical mast. The rotator will sit on a US Tower RP-3 Base Plate which is elevated approximately 3inches from the top of the base using commercial L brackets from Simpson Products. The L Brackets are anchored into the concrete using three 1/2 Inch by 8" long anchor bolts.

The Yaesu Model G450 (good for 10 Sq. Ft. of wind load) is bottom mounted on the US Tower RP-3 Plate Mounting a…

Arduinos embedded within homebrew test gear ~ N6QW Part II

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The Mystery Is Solved! As a recap, in my prior post I was just starting to investigate the use of Arduino's that could be embedded into homebrew test gear. There are many programs floating around and many incredible, and might I add, sophisticated pieces of test equipment that can be built employing the Arduino. Many of these are in Altoids Tins. But I simply wanted to learn how to generate and display data beyond push that there and pull this here. Thus I thought a simple display of a sine wave would be an easy entry for me to learn about how to generate the data and more importantly how to display the data. I should confess that my days of learning about trigonometric functions was 6 decades ago and thus I can claim that many of my brain cells have died along the way so I am missing some critical pieces of information. Which I was. The plot shown in Part I are not sine waves! They look like a sine wave because  I wanted so badly for them to look like a sine. Here is why they ar…

Arduinos embedded within Homebrew Test Equipment ~ N6QW

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More uses for the Arduino -- Test Equipment There is always something on the bench! While I await some critical antenna parts still to come and a few parts I need for the two SSB transceivers, I thought I would turn my attention back to some investigations with the Arduino Nano coupled with TFT Color Displays. I am amazed at how many sophisticated homebrew measuring devices  (many fitting in Altoids tins) are showing up in YouTube videos and on websites. Among these are Scalar Network Analyzers, Digital SWR Bridges, Audio Test Equipment and on and on. In some of my own efforts I figured out how to add a moving bar S Meter to the bottom of a color display so that up until S9 the bar was one color and beyond S9 another color. Thinking that was pretty cool my attention turned to how would you add real time plots to a color display such as you might have in checking out a homebrew crystal filter (I know this is what a SNA does). But I wanted to see what makes things tick. So my first th…

New Radios on the Bench at N6QW ~ A 20M SSB Transceiver

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More Surface Mount as Applied to a New 20M SSB XCVR Peter Parker VK3YE is probably one of the most prolific ham radio homebrewer's and you only need to look at his YouTube channel and you will be well convinced. One of his creations is called the Knobless Wonder. Basically Peter has built a simple SSB transceiver using crystals in the 40M ham band and by doing so has eliminated the need for a local oscillator. The 7 MHz BFO serves as the main frequency determining element and thus becomes essentially a single channel SSB transceiver. Brilliant idea, Peter! This keeps the circuitry simple and power consumption low. So why not? I had thought about duplicating that project and I think Peter's crystals were in the 7.150 MHz range. That would be ideal. Alas I was unable to find those crystals from US distributors but did purchase some cylindrical crystals at 7.2 MHz from Digi-Key. Somehow I don't think those are going to work too well and 7.2 Mhz here on the left coast (Califo…

New Radios on the Bench at N6QW

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New Radios in the Queue!  While I await some of the beam parts to arrive I have taken up building (or should I say rebuilding) some new radios. The two new builds are SSB transceivers with one being on 40 Meters and the second on 20 Meters. The 30M CW Transceiver is Sacrificed! In 2013 I was convinced to write an Article for QRP Quarterly that would center around a 30M CW transceiver complete with narrow filter and even an RIT. I built that project wrote the article and even had two QSO's with the radio. After having taken some nice photos for the article the radio was put into the back of the closet. That seemed a good place for the project seeing as I had no emails of inquiry and despite having some nice features no one was interested in building it. Previously I had another CW article only this one was for a 40M CW transceiver. Again not much interest. The most interest has come from my SSB radio projects and the recent LBS series of articles is testament that most new to hom…