Radio W4KAZ

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Field Day and The K3NG HomeBrew Rain Fly

With Field Day right around the corner the K3NG Home Brew Field Day Tarp Canopy seemed timely. I don’t have(i.e. “will not have”) a google account, so I couldn’t post comments to K3NG’s post. But it’s cool enough to bookmark permanently. Literally. Putting shade on the tent keeps the operating position much cooler.

My initial reaction was that K3NG’s cover would be subject to water pooling. As I kept reading, I saw that he noticed that too. Back in the swamps as a WB5, we used a similar strategery for shade and rain. Rather than risk poking holes in the tarps with center supports, our solution was to make the front posts about 18 inches longer than the rear posts. The slope was sufficient even in a heavy rain.

Our own posts were cut from pine saplings liberated from one of the club member’s farm.

With the front facing north, that also helps throw the shade a bit lower on the tents below the cover. It works pretty well at shedding rain too. Lots of chances for rain on Field Day when you are only 20 miles off the Gulf of Mexico. Ick.

O’course, it rained about three inches here at the NC KazShack Tuesday morning. My front yard becomes a small stream in these conditions, with water flowing over the driveway, down across the yard and over my neighbor’s driveway too. So much for the landscaping. Landscape timbers, mulch, even the grass – whoosh.

I sure hope the wx dries out before FD. Ugh.

Anyway, I like the rain fly solution. Kinda’ labor intensive, but worth the effort if there are enough warm bodies on hand to help throw it up.

BPFF – Guess-timating the Filter Efficacy – Part 5

Part 5 of the W4KAZ filter project series discusses filter losses, an idea for getting a very rough S-meter calibration, and trying to estimate the out of pass band attenuation provided by the filters.

The Losses:

The filters do have losses in the pass band. This is known as the insertion loss, and is reported in db. When discussing the pass band, we want the losses to be as low as possible, or approaching 0.0db of loss. The old rule of thumb is for every 3db of loss you are losing about half of your power. So, 100 watts of RF transmitted through a 3db loss component means there is only 50w coming out the other end.

Run that through the loss formula…. db loss = 10*[log(100/50)] = 10*log(2) = 10*.30103 = 3.01db of loss.

Since loss is defined as a ratio of the actual power levels, a simple watt meter and dummy load can be used to measure the losses of a component in db. That gives a nice yardstick for comparision to known commercial filters. The accuracy of the wattmeter is an issue, but part of the game is to compare the values I come up with against values measured with better test equipment. If I ever manage to hook up with one of the guys who are willing to help with that.

The set up to measure the loss in the pass band is simple.

Transmitter–> filter –> watt meter –> dummy load

By replacing the filter with a barrel connector, you can get the baseline power. The watt meter on hand here is not sensitive or accurate enough to use the same technique for measuring signals outside the passband. Not if the filters are working. 😮

Aside: This is also a good way to test a piece of unknown coaxial cable. Rather than rely on an estimate of what the loss should be for a known length of similar cable, it is pretty easy to measure the loss. A quick computation of the loss into db gives you a yardstick on the quality of the cable by comparing it to known losses specified by cable manufacturers.

The Guess-Estimate:

Anyway…. My set of NVARC filters came in measuring actual losses between 0.6db to 0.8db, and about 1.0db when installed in the integrated switch box. The set of K4VX filters came in at 0.3db to 0.6db.

The problem is that the insertion losses in the pass band tell little about their effectiveness on the 2N or N/2 harmonics.

The only tool available in the KazShack for measuring this type of loss turns out to be the S-meter on the receivers. Receivers are quite good at hearing RF. Kinda their whole purpose in life, right? The new problem is the unknown scale of the S-meter. Is it telling us anything useful?

So: How to calibrate the S-meter?

Okay. I couldn’t solve that one. Is there a possible work-around, or a way to determine the existing calibration of the S-meter?

This puts me off into an area that may eventually turn out to have little real-world validity, but here’s what I came up with. The FT-920 has a three step attenuator pad which is a known quantity. Assuming a simple resistance pad can be easily calculated and implmented by engineers capable of designing such an otherwise comlpetely slick gizmo. For some reason the pad is coincidentally in 6db steps, giving 6,12, and 18db. How convenient. 😮

The unofficial rule of thumb is that an S-unit is supposed to be 6db, with S-9 the 50 microvolt level. So with 18db attenuation, an S-9 signal should be knocked down to S-6. I don’t have a 50Ö¶ standard, one of countless other things I don’t have, but I am able to generate a signal at various levels. So I decided to use the attenuator pad to calibrate the S-meter markings. Although I may have no idea what level actually causes the meter to read S-9, I CAN use the known values to figure out the values from S-9 down, or S-9 up. I still don’t know the actual signal levels or what signal level corresponds to an S-9 meter reading, but the scale allows measurement of the relative differences in known quantities. In this case, that is exactly what I need.

What this gives me is a round-about way to guess-estimate the effectiveness of the filters where it counts, on the sub harmonics or harmonics. If I know the value of attenuation causing a signal drop from between S-9 to S-2, inserting a filter that causes that same drop will have that amount of attenuation on that frequency.

Nothing is ever THAT easy. S-meters are known far and wide for non-linear behavior, right? Sheesh. But life is full of surprises.

Previous in series: Band Pass Filter Fever – The Kludgy Switch Box – Part 4

Next in Series: BPFF – The Guess-timated Scale and actual Guess-timates – Part 6

BPFF – The Kludgy Switch Box – Part4

Part 4 of the W4KAZ filter project series comments on the process leading up to the integrated box full of NVARC Ugly filters for use in the KazShack. The quest continues.

Notes: Link to photos of the project at bottom of this page. If you want to read about the project from the beginning, go to the”Band Pass Filter Fever” series page.

Part of the project goal is to put all of the NVARC filters into a switched box to allow for SO2R and use at Field Day and on IOTA expedition. The original idea was to use a simple rotary switch. Somewhere along the way the idea morphed into using relays set up to allow control from a band decoder.Toying with the relay switching idea brought up a couple of issues that I chose to avoid. Instead, the individual filters were tied together with a two pole ten position switch.

A previous project resulted in a seven position remote antenna switch.That switch is lossy on 15m and 10m because of the point to point dead-bug style wiring. I didn’t see an easy way to avoid this problem, and I’m not set up for PCB design/manufacture. Using PCB’s and strip line runs would solve the issue. I have an idea for making strip lines that may work, but it is a bit Rube Goldberg-ish, so I chose to shelve that temporarily.

So, back to the rotary switch. I had a 2-pole 10 position switch in the junk box. The contacts are silvered brass, and seem beefy enough for the job, so I tested it out by wiring up the input/output to a bypass position.

Ick. Needless to say, it is not an ideal solution. The loss through the switch alone on 10m is about 0.6db. Losses are lower on 40m and 80m, just barely measurable.

So, WTF. I used it anyway. More suitable switches are a bit pricy if bought new, and this one was already in my sweaty little hands. Impatience, “good enough”, and zero cost won out over quality. Engineer the possible.

After all of that hand wringing was done, some other practical construction choices needed to be thought out. The end goal of constructing a switched filter box could have been implemented in several ways.

Method 1: Use the existing set of filters, switching them in via an external switch box, all connected via a rat’s nest of coax jumpers.

Method Zwei: Build another set of filters into a larger enclosure, and incorporate the switch into the new design.

Method III: Use some less aesthetically pleasing choice that will also benefit from poorly conceived and hacked together engineering practices.

Well the choice was clear – use Method III!

The rationale unfolded as a matter of “least inconvenient compromise” rather than “optimal design”. I was limited in the number of parts available. That was the primary limiting factor for method 2, not enough capacitors of the proper values on hand for a full second set of filters. Keeping the individual filters available was desirable for the sake of future flexibility, so ripping them apart and re-assembling was not considered.

Parts count also played a part in ruling out method 1, as it would use up 20-plus pl-259’s, plus the coax.

My compromised solution was to use the individual filters with a slight modification. Rather than remove the so-239 connectors, I merely tacked on a pigtail of coax for the runs to and from each switch. It is a compromise in every way, electrically, mechanically, and aesthetically. But it sure was simple.

It also seemed to work electrically better than I expected, as none of the loss figures vary substantially from the losses I would expect from the switch plus those of the original individual filters. In other words, the db losses through the filter added to the db losses from the switch in bypass add up to the total loss, when each band is measured separately.

The completed box shows losses on all bands of approximately 1.0 db. This is a bit odd, given the losses of the switch itself vary by band. But the insertion losses of the filters are lowest on 10m, and highest on 80m. Since the losses through the switch component are high on 10m and low on 80m, they all seem to coincidentally hover in the 1.0db range.

It appears that the insertion losses on 40m and 80m filters are a bit higher than the NVARC spec. This is probably because of compromises made in the physical construction, as the coils in those filters are closer to the sides of the enclosure than they should be. They were built last and the enclosure used were more difficult to work with due to their non-standard construction.

The insertion losses in the 1.0 db range are significant enough to be a concern, but everything is a compromise. This is the compromise I’m required to make for SO2R without outlay of more ca$h. The ca$h reserves are currently at less than optimal levels, but there is a lot of that going on. It will be an even larger compromise operating with low power than it would be if the filters were followed by an amplifier, but such is life. Engineer the possible!

In the grand scheme, the finished NVARC box shows about 0.2db more losses than I could expect from the commercial Dunestar series, and maybe 0.4db more loss than is expected from the W3NQN variety. On a positve note, this one cost less than $50.00USD in materials, not to mention everything I learned during the construction. The time required for construction was an educational investment, and was well spent.

Pictures of the KazShack NVARC filter box and K4VX filter sample.

Previous in series: Band Pass Filter Fever – The Guinea Pigs – Part 3

Next in series: BPFF – Guess-timating the Filter Efficacy – Part 5.

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:

  1. 10m – orange
  2. 15m – white/orange stripe
  3. 20m – green
  4. 40m – white/green stripe
  5. 80m – blue
  6. 160m-white/blue stripe
  7. 12v or gnd – brown and white with brown stripe
  8. (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 control box, and taped a sticky note inside the cover to remind me I dorked up that radio B cable assembly.

Now a bit more cable assembly will have most of the bits in place for some new operating fun.

Outstanding KazShack Issues:

  1. hoisting 15m loop
  2. 10m antenna(???what to try???)(???and why bother???)
  3. 160m antenna on ground
  4. 40m antenna switch
  5. 20m antenna switch
  6. Tuning K2 for 80m/160m
  7. Shack layout redesign
  8. Operate!

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 this never seemed to be a problem before. On the 40m antenna broadside to WPTF, the mix was S9+, and at least S7 on the other 40m and 20m antennas. So, it will probably blow my socks off when I switch to the 80m folded dipole, right?

Nope. Switching to the 80m folded dipole, the mix disappeared completely. No more WPTF audio on 3570. No more WBRZ. Both were Gone. Zip, zero, nada. Hmmmm.

Then I rememberated reading that folded dipoles were useful on their primary frequencies and their odd harmonics. So an 80m folded dipole could possibly be pressed into service on 30m, but it is deaf as a dummy load on 40m. That was a fact I have proven experimentally, both on purpose and by accidently flipping to 40m and wondering where all of the signals have gone(duh-uh!). The 80m antenna was rejecting the WPTF fourth harmonic well enough to eliminate the two station mix.

It would appear that a folded dipole also helps to reject the even sub-harmonics as well. This would probably have been obvious, but the thought had never crystalized within my addled gray matter before that moment. That fact could prove very useful for several settings. SO2R. Field Day. Field DXpeditions. IOTA. Sweet.

So, one additional yet seldom documented method to reduce the n/2 sub harmonic is to use a folded dipole. I would expect the folded dipole will also attenuate an interference your transmitter is generating on it’s 2nd harmonic, so switching either antenna to a folded dipole will probably help. This won’t help a 40m/15m problem, but applies to the other common harmonic situations.

Every little bit helps.

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 guidelines, and the coils are probably mounted less than optimally inside their cases. Through experimentation I found that slight variations in coil positioning had an effect on their insertion losses.

Additionally, the 15m filter began acting up, showing terrible losses. It turns out that in slinging it around the shield had become dislodged and was either in contact with or too close to one of the coils. Re-securing the shield solved the problem, and put the filter back very close to the NVARC spec’d performance.

By comparison, the K4VX set I have show less attenuation. I have K4VX versions for 20m, 40m, and 80m. Both the 40m and 80m filters show very low losses through the filters, both at about 0.3db of loss, only a couple of watts. The 20m version shows losses similar toits NVARC counterpart, in the vicinity of 0.7db. I expect to rebuild the 20m filter from this series using the ceramic caps rather than silver mica caps. It will be interesting to see if the loss figures change.

I have not yet built the 10m and 15m versions of this design, and may not. The attenuation specified by K4VX on these bandsis not as good as the NVARC spec. It might be worth trying the NVARC filter designwith toroids rather than air wound coils. An excellent experiment idea, and the 10m and 15m NVARC design seems to work well as described and reproduced here.

Given the low losses through the K4VX design, I may use that set for the run station, and the NVARC design for the mult station in an SO2R setting. The K4VX design is also physically much smaller, another practical advantage. The NVARC design has a better set of attenuation figures specified, but it will be nice to get actual measurements on the filters before declaring them a better choice. Some actual on-air testing can’t hurt either.

The coax stub project has been placed on the shelf for the moment. It is worth noting that coaxial stubs are probably better described as notch filters rather than band pass filters, as they are designed to place a notch on the harmonic or sub-harmonic frequencies. The book by W2VJN, “Managing Interstation Interference – Coaxial Stubs and Filters”is a treasure trove of useful information. For anyone with an interest in the subject of coaxial stubs, the book is worth every red penny of its price. Add it to your library and you won’t be displeased.

Previous in series: Band Pass Filter Fever – Untangling The Web – Part 2

Next in Series:Band Pass Filter Fever – The Kludgy Switch Box – Part 4.

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 NE/SW antenna pointing towards the eastern most tip of the NW/SE antenna. Modeling showed ther was little interaction between two dipoles in that configuration, but it seems likely they are not completely invisible to one another. I’m happy with it so far.

40m turned out so well I decided to do the same thing for 20m. The new NW/SE 20m dipole may be somewhat less productive, but maybe it will help to bag AK and NT and BC in the domestic tests. Unlike the 40m pair, these two antennas definitely show a difference in coverage into FL. Over the weekend there was one FQP station that was in the noise on the NE antenna, and peaking at S-5 on the SE antenna. (More S-meter non-linearity?)

The lesson learned here is that a single fixed dipole is leaving gaps in the coverage. The solution is simple. If it is practical to do so, adding a second dipole at 90 degrees to the original will definitely help fill in the holes. It’s not as good as a yagi, but better than a single fixed dipole. A rotatable dipole would also do the job if you remember to turn it. Note: switching between dipoles is a lot faster than a rotator, but coverage is less continuous .

S&P vs Running

Ed, N4EMG stirred the mental pot with his recent post about S&P contesting. Since I really have not met a lot of contesters that prefer S&P to running stations, it is difficult to address some of the questions Ed raises.

As luck would have it, contesting S&P with modest antennas is almost the only sort of contesting experience I have. Only in the last year have I begun to mix in runs with my more typical S&P operating. A quick glance at my scores by year page show only a couple of contests with 500+ QSO’s. 2006 Sweeps is a good sample of my best mostly S&P effort. It’s also one of the few contests I have kept my BIC for most of the duration.

Beyond that, there is not a lot of information you can use as a comparison. Unless you know the type of station someone uses, it is difficult to make comparisons. Even then, the differences in geographic location, amount of time operated in the contest, antenna height and quality, and operator skill level all come into play. Operator skill level is a tremendous factor. A good operator will run rings around a less experienced op. “Butt In Chair” factor is therefore not limited to the current contest, but is also a cumulative factor. There is no substitute for experience, and that is not unique to contesting.

Contesters seem to migrate away from all S&P fairly rapidly. Many begin that way when first discovering radiosport, although I suppose some jump in and start running right away. Folks come to the point where they realize(as Ed has) that running is the best way to increase rate. Some of the good operators will do all S&P when they are time limited, but even then most folks seem to prefer running. So the data on “all S&P” operating would be further limited if it were available at all.

Power level matters. Running with low power is a challenge. But if you want proof that good scores can be done successfully with low power and modest antennas, I’d refer anyone to look up some of the scores posted by N4YDU. Nate is a run operator, S&P’ing less often, but he is a great op and can rack up QSO’s. He has operated HP a few times, but most of his scores are in the LP category. There are also no tall towers at N4YDU. Nate has a tri-bander at about 30 feet, and a lot of various wire antennas. “Various wire antennas” because Nate likes to try out different things, including dipoles, doublets, loops, half squares, etc.

For low power, CW is the mode to concentrate on. A LP op will have more punch on CW, and better luck holding a run. But don’t expect to be able to hold a run forever with LP and modest wire antennas. There are a lot of HP stations that will see you spotted and squat only 100hz above you to poach your run fq. There are some who won’t even allow the dignity of the 100hz offset. (I have a name for those sort, but it is not suitable for refined company;) Sometimes it is worth dueling, sometimes it is just time to move along.

I personally enjoy S&P operating more than running stations. S&P is fun because it keeps me focused. My best single hour rates are just under 60 QSOS/hr on SSB, and 49 Qsos/hr on CW. The ten minute rate can and does often go higher, but I find it hard to tune, copy, and dupe check much faster than that. Better ops can S&P at higher rates, but their time is better spent running. This is probably why So2R has appeal. When runs slow down the second radio keeps one from dying of boredom in a rate productive manner. Reading a magazine seldom translates into QSOs.

I also find that rate is easier on SSB, when conditions are good. Better CW ops may find just the opposite. Probably everyone would agree that good conditions make S&P a real blast. Except for those that hate S&P.

S&P is really fun when three or four bands are open at the same time. 10m is also fun when it opens. On 10m SSB the bandwidth is so large that by the time you have finished the first S&P pass across the band and start a second pass, all of the run stations might be new ones. That is fun, and I sure hope it happens again. The sooner the better!

Other ways to improve S&P rate are by using packet spots and making use of the temporary memories, if your logging software supports them. I use the memories for those juicy mults/DX. Writelog has three. I generally load two stations needed in the first two memories, and the current frequency into the last. Then I can toggle back and forth between then using mouse clicks as if they were spots.

Even when not connected to packet, using the band map window to load Q’s is useful. By loading a station into the band map, I get to see a “preview” of who might be there when I scan through the second and third times.

A lot of the QRP and LP stations have good antenna systems. QRP is a challenge of a different sort for them. Great antennas are better than QRO, because they work on receive too.

Just some ideas, some of which you already have probably either used or seen elsewhere before. However you choose to do it, concentrate on the fun first. That’s the motivator for everything else.

Simple Two Position Remote Antenna Switch

The current plan is to incorporate a SixPak into the antenna switching scheme here in the KazShack. The SixPak is to help enable an exploratory foray into SO2R operating.

It would also be useful to have the ability to use more than one resonant antenna on a given band. For example, the station is currently limited to a single dipole on 40 meters. It would possibly be helpful to have another dipole at right angles to the first. This would likely help bring up stations that are off the ends of the current dipole. It might be even more helpful on 20m where the antennas are higher relative to the percentage of the bands wavelength.

So a quickie two antenna remote switch is in order.

Two Position SwitchTwo Position Switch W4KAZ SwitchW4KAZ Switch

The requirements are not critical for my low power application. It is simple enough. The relay is the P&B RTB14012F, a SPDT relay rated at 12A in its normal general purpose AC applications. This series of relays has been in use in my seven position switch for a couple of years now, and is in the same series of relays used in several high power switch project articles from NCJ. In this specific switch there are no losses that are measurable up through 6m. This was tested only with an ordinary watt meter into a dummy load, and applies to either output port of the switch. So far so good.

The only other components are a clamping diode, a 10nf bypass capacitor, a few bits of hook-up wire, and three coax connectors. The diode and the cap go across the coil on the relay to suppress nasty RF side-effects on the DC side of the circuit. The enclosure was easily the most expensive item. Total cost is about $12 USD. The 12v control cables are potted with hot glue. The enclosure is not water tight, but the switch will be mounted in or under a rain shield. The relay itself is sealed, so insects might be the only issue should they infiltrate the enclosure.

The switching controls are going to be in a yet to be determined integrated panel. That will add to the cost by the amount of the switch which will be mounted in the control panel. Cat5e will be used for all control cable runs.

I expect to place this puppy between the SixPak and the 40m antennas. Coax stubs for 40m will connect the SixPak to the two position switch. The default position(switch off) will be the primary antenna facing NE/SW. There will not be a grounded or unused position, as lightning protection will be added at the “radio A/radio B” positions of the SixPak. That arrangement will keep the radios isolated from one another via the SixPak, and unable to simultaneously select antennas resonant on the same band. (maybe….depends on the antennas used for the other bands, aina?)

With the addition of one relay and one extra control wire, it is easy to make a similar three or four position switch.

Sometimes simplicity is good, or as in this case, “good enough”.

Sweepstakes 2008 CW Score

Scores for the 2008 CW Sweepstakes have been published on the Web. The Sweepstakes LCR report is always worth looking over, since my error rate is still far too high on CW. For 2008, it looks like 44% of my errors were on the check number. The errors on the exchange was about 45%, and I busted only four callsigns. The score suffered dramatically, but I showed some incremental improvement over the 2007 Sweepstakes. I didn’t match the improvement in error rates I managed in the 2007 IARU, but it was better than the error rate of the 2007 CWSweeps.

The callsign copy needs to be 100%, but I made progress in that area over 2007.

The big problem seems to be busts on 7&8 and 2&3. Not a surprise. That mistake is accounting for the bulk of the cross check number busts. It is also the biggest problem in the exchange busts, where the year license is busted because of 7&8 or 2&3 busts. By correcting this copy error I will clean up almost 80 percent of my over all bust rate.

The other remaining errors are a mixed bag. There are several transposed digits in year licensed(e.g., where I logged 67 instead of the correct 76). This is a typing dyslexia that I often can catch as it is happening. So more attention to detail is needed when typing.

The rest are just generic inexusable errors. The callsign busts are fixable. “agn? ?”

Overall, I’m disappointed in the lack of overall improvement in clean copy. The score suffered mightily. But it still holds up as my best ever CW score, despite the inadequate copy. Besides, it was a blast.

K8AC, AA4NC, and N4AF all won their categories here in the Roanoke Division. Cool.