Radio W4KAZ

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SixPak Online

Finished wiring up the control cables for the Array Solutions SixPak. There’s a mistake on one of the control cable assemblies that were too hastily assembled, a W4KAZ problem, not anything wrong with the SixPak. The work around was easier than re-wiring the cable, so I just re-connected the wires inside the control box to fix the problem.

Using Cat5 cable, the color coding inside the KazShack “Should Be” as follows:

10m – orange 15m – white/orange stripe 20m – green 40m – white/green stripe 80m – blue 160m-white/blue stripe 12v or gnd – brown and white with brown stripe (tied to #7)

Note: The SixPak wiring block in the controlboxallows 12v+ to be sent down one cable and 12v gnd on the other cable. I could just have easily sent 12v+ down wire #7 and used wire # 8 for ground. That would allow the SixPak to function using either switch position alone with a single control cable. That’s also probably how most folks would wire the cables, since at leastone radiowill work when wired that way.

For quick connects, I used a set of 8-wire computer power cable extensions(ATX power extensions). Each extension is 8 inches long, and cutting one in half gives a mating connector pair. Easy enough to splice on, but I obviously screwed one up somewhere. When testing, Radio B was found to have 10m/40m and 15m/20m pairs reversed. Again, rather than re work the cable, I just rewired the four appropriate wires inside the […]

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Pollenating The Antennas – More 80m Folded Dipole

Whilst toying with some new KazShack toys, I found out an interesting and useful fun fact. The 80m folded dipole does a great job at ignoring some of the AM harmonic mixes. Death to harmonics! W4SAT seems to have the best on-line description of a folded dipole.There is very little written on the internet about this great antenna option. My own original post has a link to a web reprint of the original ARRL design article.

The KazShack is less than a mile from the 50KW WPTF(680) transmitter, and only about two miles from the 10KW WRBZ(850) transmitter. This results in all manner of harmonics and harmonic mixes that I can hear and identify. Pretty much any combination of the numbers 680 and 850 added and subtracted together produce a frequency that have audible audio artifacts that can be identified as from either AM station. Some of the mixes are much worse than others. Some are barely audible. The mixes that fall within the ham bands are obviously the ones of the most pertinent concern.

While playing with some new home brew band pass filters filters and the SixPak, I flipped the radio to 80m. While connected to either 40m antenna or the 20m antenna, I could hear a loud garbled mix centered at about 3570. The WPTF audio was clear. The WBRZ audio was also identifiable, although very garbled. That works out to the 4th harmonic of WPTF mixed with WBRZ’s 850. (i.e., [4*680]+850=3570)

This seemed really curious, since […]

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BPFF – The Guinea Pigs – Part3

So, a long hiatus between band pass filter musings. In Part 1, I laid out several reference sources for band pass filter projects. Part 2 details the decision process, plus some notes on what happened with initial attempts at reproducing the K4VX Filter and NVARC filter projects.

Here I have a bit more detail on each project. After obtaining a small supply of the capacitors specified by the NVARC design, I’ve completed the 40m and 80m filters.

Measurements on the 40m NVARC filter show about 0.8db loss through the filter, with the SWR pass band covering the entire band easily. Outside the band, the SWR rises rapidly above 7.370 Mc, and below about 6.775Mc. That would seem to indicate the filter is resonant lower in the band, but it actually shows about 2 watts more attenuation at the bottom of the CW segment than it does at top of the SSB area.

The 80m NVARC filter also shows about 0.8db of loss through the filter. The SWR is about 1.5:1 across the entire band, and the filter seens to have its sweet spot right near the SSB DX window at about 3.775 Mc. That should prove fortuitous, since it is also where my 80m folded dipole resonates, but it is completely by chance.

These last two filters probably have slightly higher losses than they should due to construction techniques. The cases I had available for their enclosures were not ideal. Their assembly did not allow easy construction by the NVARC […]

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Lost Island DX Society

Don’t miss the best source for up to date contesting news available on the internet. The new source for all manner of contest trivial is now up and running at the home page of the Lost Island DX Society. I sure wish I were going to be at Hamvention this year to catch the L.I.D.S. hospitality suite.

PVRC Contesting Webinars

PVRC club members received word from PVRC president Ken, K4ZW, that PVRC will be introducing a series of Webinars on various contest subjects. Jamie, NS3T has a news release posted with a bit more info. Most of the webinars will be available to all contesters, although I suspect there may be a few club internal “stategery” sessions held more tightly to the vest.

I sprung for the original PVRC 2005 “Contest College” DVD, which has a lot of great information on it. Not every subject was a priority interest to me personally(e.g., VHF contesting), but each was well conceived and delivered. Really wanted to make the original PVRC “Contest College” in VA, but could not.

PVRC Contest College evolved quickly beyond the club into Contest University at Dayton Hamvention, and has already been taken internationally by K3LR, drawing on local talent for lecture sessions. Given the hundreds of years experience held in the minds of so many great operators and technical folks, this is a great idea.

A repository of simlar webinars would be a great asset. It will be of greatest benefit to folks who are in rural areas, and not able to get the sort of elmering that can be obtained by joining a club, or who cannot make a long pilgrimage to CTU at Hamvention.

Built it, and they will come….

Time to Kill

Or a way to kill time. WB4AEJ has a matrix with a slew of assorted hame domain links. Just scratched the surface….

Pollenating the Antennas – Crossed Dipoles on 40m and 20m

The tree pollen is really flying now. It is thick enough that it looks like a light snowfall or a misty rain when seen with the sun at the right angle. (Ahhhh-CHOOO!)

Pollen must be good for antennas. Two new ones sprouted up over the past weekend on new lines I shot into the biological supports before the kids’ spring break from skool.

I somewhat reluctantly packed up the 15m/10m nested rectangular loops. The support was just too good a height(about 15m/50 ft.) and location to leave it being used on relatively unproductive bands. In its place there is now a 40m dipole that favors the NW/SE directions. A bit of tuning around the 40m band doing A/B comparisons between the new dipole and the old NE/SW dipole showed promising results. The new dipole is much better into 8-land and 9-land. The old is better into 2-land and Europe. For some reason most of FL seems about the same on both. Interesting.

The differences on rx signal strength is more than I expected in a lot of cases. It makes little difference for strong signals, but a lot of difference on weaker signals. Hopefully this will help add Q’s to the contest logs. It also is a bit of commentary on the non-linearity of S-meters.

The antennas are at an almost perfect 90 degree angle to one another. They do not actually cross one another. Looking down from above they form an L shape with the south end of the […]

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