Wednesday, June 27, 2012

Thoughts on the 2012 Field Day

It would seem that planning pays off!

That should be no surprise, provided realistic expectations, of course!  Since this was our 20th year at this same location we pretty much knew the lay of the land, where we can put things and what works where since we've tried various permutations over the years.

One of the biggest helps was that we had the enthusiastic participation of some excellent CW (Morse) operators that managed to keep that station on the air for all of the 24 hours, and since CW contacts count for more points than SSB (voice) contacts and that over the long term, a reasonably experienced CW op can work stations faster than a similarly-experienced SSB op, the effect is magnified.

This year we used the club's 85 foot tower/generator trailer (the "COW" - which stands for "Communication On Wheels") to hoist both the 4 element Triband Yagi as well as an anchor point for wire antennas as well as our much smaller 30-ish foot tower/trailer (dubbed the "calf") for the opposite end of a very long (300 feet/100 meters or so) of a span that also supported two 105 foot dipoles, each fed with ladder line.

We also had the good fortune of one of the main CW operators bringing his own Spiderbeam/mast assembly - the assembly and raising of which was a sight to behold - which, counting the 3 element tribander on the short tower (at about 35 feet) brought our total up to 3 rotatable gain antennas for the upper bands (e.g. 20, 15 and 10 meters.)

This year we also did something that we'd not done for several years:  A wire "Vee" beam (resembling 1/2 of a Rhombic) - this time with its feed point attached from a rope connected to the top of the 85 foot tower.  This consists simply of a "Vee" of two wires, fed with ladder line, with legs about 350 feet long each (approximately 100 meters) separated at an angle of approximately 20 degrees (more or less) with the ends being attached to conveniently-located trees off in the distance:  Being in a forest clearing gave us a reasonable choice in trees!

This antenna was directly compared to the 4 element Yagi and found, in most cases, to be superior - with the added advantage (for a contest like Field Day, anyway) that it is bidirectional meaning that we could work both east and west coast stations without having to constantly spin a Yagi or park it on a compromise bearing.  For those stations to the north and south the Vee Beam worked quite well as it had a reasonable amount of gain in that direction too - or at least better than the east-pointing Yagi!

Of course, one can't have field day without a few issues cropping up, but this year was much less of "what we did wrong" and much more of "how can we do better next year."  A few of these include:
  • We can easily (and safely) increase the height of the mast on our short tower (on the "calf") which should put a Yagi placed on it in the 40-45 foot area with the tie-off for the long antenna span from the other tower at the 35-38 foot area.  (The Yagi is mounted on a 6-ish foot mast above the rotator.)
  • Perhaps another Vee Beam that is optimized to work better on 40/75 meters.  This year, I worked all of the 75 meter SSB contacts and while relatively quiet band conditions and a good antenna fed via ladder line from a high-power low-loss tuner/balun helped, a few dB more gain would also be nice!
  • A bit better managing of the some of the stations.  The main CW station was no problem, but we could probably have done a bit better in keeping all three of the stations active at the same time.  As it was we always did have at least one CW and one SSB running at all hours and the third could have easily supported CW or SSB during the "off" time.
  • We somehow blew it in taking the opportunity of the main Saturday meal as being a social event.  In past years we managed to corral most of the site's occupants in one large, somewhat shaded area where conversations could happen and people could meet and introduce themselves to each other, but the way things ended up being laid out this year there was no obvious place to gather, so it didn't really happen.
One good success was the introduction/teaching of hams new to the hobby and/or new to HF operation - both via the GOTA ("Get On The Air") station and via mentoring on the main stations as well as various tours and explanations/answering of questions.

On Saturday evening and Sunday morning, we couldn't help but notice a large plume of smoke billowing up to the south of us.  This turned out to be due to a large wild fire that had flared up some 20 miles to the south, casting its pall of smoke over the landscape to the north.  While we were on site it was of no actual threat although on Sunday evening, it was reported that a nearby campground had been evacuated due to high winds having quickly spread the fire many miles to the north in just a matter of hours.  Hopefully our trees will still be there next year!

[End]

This page stolen from ka7oei.blogspot.com

Tuesday, June 19, 2012

Field Day preparations continue

A while ago (May 10) I wrote about Amateur Radio Field Day preparations for the Utah Amateur Radio Club (UARC.)  As with all such plans and organizations, things don't go exactly as one intends/hopes but if a bit of flexibility is built into the grand scheme, punching a few holes here or there isn't going to cause a disaster.

Last year's UARC Field Day came about the closest in recent memory to being a disaster.  Due to a bit of miscommunication, boxes showed up at the Field Day site - located some 2 hours south of Salt Lake City - that were not the ones containing important items such as radios, microphones, power supplies, etc. necessitating an early morning run (post-midnight departure from the site) back to where we store our gear with a return around 3-4 AM - and using about $80 in gas!

The next morning (Saturday, the first day of Field Day) we fired up the generator - an 8kW propane unit mounted on the trailer with our 85 foot tilt-up tower - and discovered that the motor tilt-up motor was seized.  Undoing a few screws on its housing, we let a pint or so of rusty water pour out of it and broke it loose, but it no longer hummed when we pushed the "UP" switch.  See the note at the end of this entry for a few words on what happened and the "fix."

Fortunately, this wasn't the motor that actually elevated the tower so 20-30 minutes of people trading off, manually turning the pulley brought the tower to an erected and locked position whereupon the elevation to its full height using the motor that did work could commence.

At noon - the time at which Field Day starts in these parts - we were still rummaging around madly finding bits and pieces to get the stations on the air and we didn't emit our first cycles of RF from our CW until just about 5 minutes or so after Field Day had started with the SSB station going a short time after that.

Fortunately, those were the majority of the difficulties that we had last year that would have seriously hampered our operation:  They say that disasters come in threes, and that count seemed about right last year!

If we had gone through all of that last year and hadn't learned anything I'd say that we'd deserve everything that fate would throw at us, but this year we made a conscious effort to avoid repetition of the more egregious of our mistakes.

Here are a few random comments on our planning this year:
  • A bit more careful planning.  This should be an obvious one, but its probably the most commonly overlooked point.  To a degree, it was assumed (there's that word!) that everyone knew more-or-less what to do.  Up to a point, this is fine - if everyone involved has done it before, but if one gets new blood in the group a bit of extra mentoring is a really good idea!
  • Go through the gear beforehand.  This isn't a problem unique to last year:  At the end of Field Day everything seems to get thrown into boxes and heaved into vehicle and then unloaded again for storage.  This is fine as long as someone makes sure that all of the gear gets back but it's often the case that it isn't until setup time next year that anyone actually looks in the boxes and discovers that things have been moved around and that critical pieces are where they are supposed to be.  What inevitably happens is that items have magically found their way into boxes that no-one thought bring the next year  ("Why are the microphones in the box with the TV twinlead - and why do we even have a box with TV twinlead, anyway?")  This year we made a special point of assembling all of the critical gear and putting it all together we well as throwing out junk that was not only useless, but a liability should it actually be used.
  • Occasionally rebuild things like antennas, feedlines and patch cords.  Over the years, our wire antennas have seemed to have mutated from simple (but effective!) wire dipoles to things fed with twisted-together ladder line that led to trap dipoles that had had their traps bypassed with wires.  This year, about all we saved of these old antennas were the longer pieces of ladder line and the insulators, sending much of the rest off to be recycled.  We also bought a case of one particular type of cord reel that seemed to do a better job of accommodating both the antenna and its feedline while being easier to use and have some hope of fitting into reasonable-sized storage boxes.
  • Prevent the antennas from just "happening."  Years ago, we decided on placing our two triband Yagis and towers in a north-south line allowing each station to point east or west (where the vast majority of QSOs will be found from our Utah location) and not at each other.  Being separated by several hundred feet, this allows good separation to keep the stations out of each others' receivers as well as tall mounting points between which our wire antennas may be run.  Last year - because it "happened" - we somehow ended up with our two lower-band (80/40) wire antennas end-to-end adjacent to each other on the main span between the towers which meant that we couldn't help but to clobber each other.  Worse, this wasn't "discovered" to be a problem until it was too dark/late (when 10/15/20 closed and 40/75/80 meters opened) to heave/shoot ropes into the trees and erect yet another wire.
  • The other sticking point was that we didn't seem to have enough "whole" pieces of ladder line hanging around to connect an antenna to its radio that might be 200 feet away.  Reluctantly, for one antenna we had to use coax, instead - particularly runs of RG-58 and "Mini-8."  Now on 40/80 meters with resonant antennas, the extra 2dB or so loss isn't a big deal, but these were not resonant antennas.  As noted above, we've rebuilt antennas with plenty of ladder line available.
  • On the above point, if you run non-resonant antennas and feed them with ladder line into a tuner that can handle the power (100 watts or so) you are pretty well off, but as mentioned above at least one of our antennas had to be force-fed with coax which can result in high losses if the antenna's nowhere near 50 ohms.  The other problem was that we seemed to have a dearth of tuners with baluns that could handle the power!  One of our members happened to have a 300 watt MFJ antenna with a balun, but we discovered to our chagrin that its capacitors would arc over at anything above 30 watts or so given the load that was presented at the feedline - so QSOs seemed to be rather hard-fought and sparse.  Not only did this mean that we had to run QRP on an SSB station on a noisy 75 meters, but the tuner's tuning didn't "feel" right.  It wasn't until very early in the morning (3-4 AM or) that the last CW operator hit the sack and I was able to steal a "good" tuner and realized that the MFJ was probably operating inefficiently as well!  Upon "tuner replacement" I was suddenly able to easily make QSOs!  This year, the club will be equipped with a "new" Heathkit tuner easily capable of 1.5kW (picked up at a swap meet and refurbished) and several members will (hopefully) bring along decent, large tuners of their own as well!
  • As noted on the May 10 entry I'd analyze the "hiss" that the club's radios (Kenwood TS-450's) emitted on the ham bands equal to and lower than that on which they were operating and determined that if one simply had the tuner engaged (even when running into a matched 50 ohm load such as the Yagi) the out-of-band noise would be reduced by 8-25 dB, depending on configuration while losing less than 1dB of transmit power.  Simply knowing this should allow us to operate our multiple HF stations simultaneously while managing the inevitable QRM that results to levels that will hopefully be of little consequence.  We've managed to do this in years past - probably a bit serendipitously - and we hope to do this again.  With our better equipment organization, we'll also have the potential of wielding some of our filters and stubs to further-reduce interactions between stations!
  • A bit better organization of the station operation itself.  One of the most important aspects of all of this is to expose hams (particularly new hams!) to the frenetic pace of Field Day activity - particularly on HF.  Considering that one of the main purposes of Field Day is to test our ability as hams to operate in a manner similar to that which might be encountered in an emergency situation, what better opportunity to give newly-minted hams, those who have not yet operated on HF or even non-hams a bit of mentored on-the-air experience?  One aspect of UARC's field-day operations has always been a bit of a more casual operational atmosphere where one can learn under less pressure that might be encountered in operations where the goal is the highest number of Q's (QSOs - or contacts) possible!  To an extent, we try to have several stations and/or times-of-day where all levels of operation can be accommodated and this year we'll take more care than in recent years.  Hopefully we'll also have more operators willing to keep more than one station on the air in the wee hours of the morning.
Every year things are similar, but they are also different - particularly since some previous attendees don't show up and that new people appear.  As with any organized, recurring activity it is always a challenge to "pass along knowledge" - particularly that of lessons learned but at the same time it's always good to have new people come along to gain new experience, bring along different (and sometimes better!) ideas!

After this year's Field Day I'll be sure to have a few additional comments on how things went - and what we'll want to do different next year!

73!

P.S.  As it turns out, the elevation motor - which is mostly stainless steel - was none the worse for wear after the water was drained from it.  Even though it would not go up when called to do so, it did go down and in the later months we diagnosed a problem with the limit switch.  What had happened was that the jacket had shrunk away from the "SO" cord that connected to the switch and the combination of water, insects and the lack of a strain relief had caused one wire to become disconnected - the one that allowed it to go "up."  A re-dressing of the wire, cleaning of the switch and replacement of the ring lugs restored proper operation.

As for the motor itself, snow had settled on it over the previous winter and through condensation and gradual ingress, had filled the inside of the motor.  To prevent this from happening again a "hat" was made from galvanized sheet metal that prevented snow from accumulating on top of the motor while providing plenty of space for ventilation while avoiding yet another place in which hornets would build their nest!

[End]

This page stolen from ka7oei.blogspot.com

Wednesday, June 6, 2012

A suspiciously round sunspot...

Figure 1:
Venus, just appearing at 1609 MDT - in the upper-left edge of
the disk.
Click on the image for a larger version.
I decided that I'll contribute to the frenzy of what are likely to be many thousands (or millions!) of pictures that have/will appear(ed) on the web of the Transit of Venus that occurred yesterday, on the 5th of June in North America.

Here in the Salt Lake area the weather degraded rapidly over the day from the 90's F on Monday to something in the high 50's or low 60's just 24 hours later.  In the valley itself, the broken clouds in the morning degenerated to swirling layers of clouds moving in opposite directions, each conspiring to obscure the view of the event taking place well above them.

Only somewhat daunted, I set up my telescope at work and hoped for the occasional, brief respite of clouds.  Prior to the start of the transit I got enough glimpses to get the telescope aligned so that the tracking motor was doing a reasonable job of keeping the occasionally-visible solar disk within the viewfinder when it was visible, but most of the time the view was completely black, the solar filter being too dark to allow a view of the clouds themselves.

Figure 2:
Just three minutes later, a large nibble taken by Venus!
Click on the image for a larger version.
Finally, at about 9 minutes past 4 PM local time there was a brief clearing and it took a moment of staring at the disk to spot the round imperfection - a small nibble out of the upper-right corner of the picture.  The picture itself is somewhat fuzzy - despite the use of an 8" reflector telescope - because it was shot through a thin layer of clouds.

About 3 minutes later, I had another brief clearing and the apparent imperfection on the sun had visibly changed.

Figure 3:
The view at 1911 MDT.  If you can't spot
Venus now, you need new glasses!
Click on the image for a larger version.
Soon after this, the clouds got darker and thicker and I figured that this was to be the last opportunity to photograph the event from the Salt Lake Valley - which was too bad since I'd planned to haul my telescope across town to my parents place so that they could take a look.

Fortunately, there was a backup plan.  As it turned out, the cloudy weather in the Salt Lake valley was not occurring 40 or so miles south in Utah county, so I packed up the telescope, picked up my Mom (my Dad couldn't leave due to other obligations...) and went south and upon crossing over the traverse mountain range that separates the two valleys, it looked much more promising with Provo and points south being bathed in sunlight.  Coordinating with my younger brother, we met in Provo, setting up in a location with a decent view toward the west, just as the clouds covered the sun.

Fortunately, we didn't have to wait for very long for a view with the clouds scutting past, sometimes providing a dramatic effect to the shot.  Since it had been nearly two hours since I'd last seen the sun, the change in Venus' position was extremely obvious, as you can see from the picture.

Figure 4:
One of the last views of the sun at 2015 MDT
before the sun set below the local horizon.
Click on the image for a larger version.

Over the next hour or so the sun came and went through breaks in the clouds and we finally lost sight of it when it dipped below buildings to the west of us, getting noticeably fuzzier as it got lower in the west - and probably due to thin clouds in front of it.

By this point, it was starting to get cold so we finished our pizza, talked for a while and then headed back home.

All in all, it was certainly worth the time it took to see something that very few alive today will see when it happens again in 2117.

[End]

This page stolen from ka7oei.blogspot.com

Monday, June 4, 2012

It's hiking season again!

One of the lesser-known aspects of living in the Salt Lake City area is that we are next door to large areas of relative wilderness - that is, I can get in my car and in well under an hour, be hiking in a location that is about a mile higher in elevation and 10-20 degrees F cooler.

I don't get as much time to hike as I used to, but during the summer months I do make it a special point to go on a "Wednesday Night Hike" after work, a welcome diversion in the middle of the week that puts one closer to the sky and farther away from the rest of the world for a few hours.
Figure 1:
Twin Peaks Cirque from June 10, 2009
Click on the image for a larger version.

I don't know how long, exactly, these have been going on, but it's certainly been since the late 80's at least and I've been going on them for at least 20 years now and in that time, I've probably hiked around 1200 miles on just those hikes and have worn out at least dozen soles on my hiking boots!

The ages of those in our group vary, but it's not too uncommon to have those in the 20's hiking along with those in their late 60's or early 70's.  As you might guess, the hiking abilities and speeds within in the group tend to vary so we usually break up in two or more groups, rejoining occasionally when we stop at a particularly picturesque or notable landmark and, most certainly, when we get to that hike's destination!

The group that I hike with isn't exclusive, although it does consist largely of friends of mine that are also amateur radio ("ham") operators and, as you might expect, we tend to bring along with us 2-meter handie-talkies so that we can keep in touch with each other - a particularly useful feature considering our tendency to split into groups!  While we could, in theory, keep in touch with each other via more "modern" means such as texting or cell/mobile phones, you really can't safely text while walking and in many places, cell coverage is spotty-to-nonexistent anyway - even though we are less than 10 miles away from the Salt Lake Valley! Plus there's the simple fact that with "old-school" radios, everyone on the frequency can hear what is being said:  That's a lot harder to do on a phone even if you do happen to have good coverage!  In the event that someone got hurt or lost, the radios have proven to invaluable as they would be a reliable link to someone who did have good phone coverage should the need arise to summon the emergency services.

Being that most of us are ham operators, we also tend to be a bit nerdy, bringing along with us little bits of high-tech civilization in addition to our handie-talkies such as digital cameras and GPS receivers.  I'm fully aware that for many people, hiking in the mountains is an escape from the "real world" (a relative term, if you think about it!) and bringing such stuff along would be considered counter to the intent!

Since I've been doing these hikes for 20+ years and some of our group for longer, we often do the same trails year after year, but this isn't surprising since we have two important limitations:
  • Since we don't meet to start hiking until after 6 PM, we have to choose something that is relatively close-by.
  • Whatever we pick, we should be able to return to the vehicles by 11 pm at the latest since many of us have to be back at work the next morning.
Figure 2:
The pika - a member of the rabbit family:  Often heard, but rarely seen!
Click on the image for a larger version.
While there are a great many possibilities near the Salt Lake area, we tend to stay largely in the "Tri-Canyon" area, that is the Big and Little Cottonwood Canyons and Mill Creek canyon with occasional forays into the minor canyons nearby.  Even though we do many of the same hikes year after year, it's always interesting to see what has changed, what plants and flowers are doing at that time as well as catching frequent glimpses of wild animals from the common deer to the rarer animals such as salamander, pika, bighorn sheep and the (very) occasional mountain lion or bear!

Our hikes are generally bracketed by the period during which there is both little snow in the mountains at the beginning and ended when we no longer have a reasonable amount of sunlight and this means that we generally start at the end of May or early June.  Ironically, what this also means is that many of our longer (and often more strenuous) hikes are early in the season, often before many of us have hiked much during the year and we are more likely to be out-of-shape - and then by the time that we are in reasonable shape, the hikes are often easier and shorter!

As it turns out, I've been chronicling our weekly hikes in detail since 2004, keeping general track of where we went - often using GPS information - taking pictures and then writing a short account of what happened (which may be found here.)  Over the years it has been interesting to see how the landscape has changed, when we've been doing various hikes, and how we have changed as well!

Over the summer, I'll likely make a few more mentions of these hikes and what we've done/seen...

[End]

This page stolen from ka7oei.blogspot.com