Mercury Mount St. Helens - converted from old site

A PENchant for CW

Post date: Jan 20, 2014 3:27:33 AM

By the time I finished helping get fires started, etc., it was 5:30 and pretty dark, but I wanted to at least accomplish my primary goal: have the HF station ready to go by 8:00 the next morning, so I could check into the NW North America ERC and Mercury NW nets on 75m. I set up a table for the gear, and some of the boys (Hey, KF7UAG was there; I should've put him to work!) helped me get an HF antenna up.

I brought a 3/4" nut to use as a weight, and attached it to some lightweight nylon mono-filament (fishing line - $1.88 however many decades ago at Kmart). We (okay, Robert) threw it over one of the few limbs in the area that had a reasonably clear space on one side of it, and was low enough that we could actually throw over it. (I was wishing for a slingshot, etc.). We then attached a heavier string to it and pulled it over, then used the string to hoist the aluminum electric fence wire I was using as an antenna. Stretched diagonally across the driveway to the radio, the wire only ended up being about 35' long, but it was in the air! We sent another 50' or so of wire through the undergrowth to the adjacent property as a counterpoise, and we were set to go. (All this was done in the dark with flashlights.)

Oh no!

The HF station was all set up, and it was magnificent. I sat down at the operating position to arrange things, and to my horror I realized that...(look closely at the front of the HF rig shown above; see anything missing?)...it had no microphone! I had completely forgotten to look for one while I was packing. Wow, that shock hit me like a Louisville Slugger! After a few stunned seconds of silence, I started laughing at my fateful omission, and began consider ways that I might work around this unexpected challenge.

I didn't bring a lot of electronic parts with me (did bring solder and a torch, though!), and trying to adapt another microphone to that radio in a non-destructive manner (and have it reasonably reliable) was out of the question. My thoughts then turned to CW. Certainly, the radio had a connection on the back for a key -- probably just keyed to ground, and I could probably tap a wire against the chassis to key it. Sure, I don't know Morse code, but if I could find a chart somewhere, I could write myself a "cheat sheet" with key phrases that I could use to check in and report my info to the ERC net. The NC might not know code either, but there are usually a couple of guys listening who do, so while it may not be pretty, it should work. With that brightening thought in mind, I went back to working on the radio.

The antenna was sufficiently long; it only took about 9 μH of inductance (1/3 of the tuner's range) to "lengthen" the antenna to where it needed to be for 3.815 MHz. It was between 6:30 and 7:00, and the lower bands -- esp. 80m -- were hopping! Plenty of good talk, and I was pleased with the reception -- and confident that I would be able to get out well enough to reach most people on the nets.

Terrible pun. Story to follow....

Field trip!

Friday evening, I took Alexander, KF7ZIM, to an "overnight planning meeting" (can you say "management retreat?") for the young men at church, at the east end of Swift Reservoir. Last time I went, I regretted not bringing more radio gear (all I had was my Wouxun KG-UV1P HT and maybe my old Alinco DR-590 mobile, neither one with many channels programmed), so this time I went all out and tried to come well-equipped for field operation on both HF and VHF.

As usual, click photos to enlarge.

I was anxious to see if any 2m repeaters were usable from there, so I brought the well-programmed IC-208H from my office, along with a map printed from epeaterbook.com. On the HF side of things, a couple of weeks ago, Alexander helped my build new power cables (12 VDC + 120 VAC) for my Yaesu FT-101, so it was convenient having a radio that didn't require an external inverter. I also thought it would be a bit of a kick to operate a rig with tubes in the field. Knowing that I wouldn't be raising the perfect antenna farm out there, I also brought an automatic antenna tuner and a dummy load. (Tune the transmitter to the dummy, then flip over to the auto-tuner attached to the antenna and let it work its magic; as long as it can match, no further tweaking of the output network on the radio's needed.)

Setup begins

At this point I turned my attention to the VHF portion of the station. I determined that there were about 4 repeaters (including W7DG Woodland) that I could just barely hit w/ the whip on the car, and I hoped that with a better antenna a little higher, I might be able to see a noticeable improvement. It looked like the most likely way to get good clearance from both the ground and trees would be to suspend the antenna from a point near the top of the wire that I had going up to the tree limb. It was getting late, I was now mostly by myself, and I didn't want to disturb my HF antenna for fear of breaking something, so I decided to play with a lesser location until after the nets in the morning.

After leaving for half an hour to eat dinner, though, I came back and thought someone had messed with the station -- tripped over the antenna or something -- because it was all but dead! It took me a while to verify that everything was functioning the same as before -- there just weren't any conversations. Everyone stopped talking around 7:00, leaving nothing but CW at the low end of the band. I thought maybe the MUF had plummeted, but 160m remained pretty quiet, too. (It doesn't seem that popular anyway, though; I know a lot of people have a hard time tuning it and it's harder to build an effective antenna for it; that might explain the lack of increased traffic on that band.)I managed to find an app on my phone that included a Morse Code reference page, so I used that to prepare a cheat sheet with a selection of key words that I could put together (and enough letters that I could make new words in a pinch). I decided that the actual construction of the keying mechanism could be put off until morning.

Now for VHF...

We tried to get tree close to the radio station, but ended up breaking a line and getting my nut stuck in the tree, and we were also nervous about throwing rocks and such with cars nearby, so we finally settled on a low floppy limb that left the radials floating about a foot off the ground (See picture to the right). As expected, it was no improvement over the car.Morning time is MacGyver Time!

The next morning I was up at 7:00 and examining the station. It used a 1/4" phone jack for keying, something I couldn't easily build a plug for, so I looked at other options. I figured that if all else failed, I could use the MOX/PTT/VOX toggle switch on the front (usually used for tuning) to turn the carrier on and off. Alexander suggested sticking something in the mic jack to hit the PTT pin. At first I was hesitant, not having a schematic, but then I figured that out of 4 pins, one was probably ground anyway, one was the pin that I wanted, one was voice (okay to short) and the fourth one was either not used or would likely survive a brief short to ground without problem, even if that's not what was supposed to be done with it.

I had a metal ballpoint pen with me, and I began inserting it into the jack, shorting each pin in turn to the shield. On the 4th one...click! That magical sound of a transmit relay. I found that by resting my wrist on the table and inserting the tip of the pen into the jack, sliding it against the sleeve of the jack, I could make and break contact with the desired pin fairly nimbly and reliably. Unfortunately, switching from receive to transmit required switching a stiff mode knob at least 2 positions from LSB to TUNE (3 for CW), and I knew that my tone would likely be higher than most people would find pleasant, but those were minor issues that couldn't be helped. Satisfied, I sat back and waited.

When ERC check-ins were solicited and a lull in the responses occured, I threw out my callsign. It took a couple of times before it was generally realized that someone was attempting to use CW, and someone who knew code could catch my call. Delighted to be acknowledged, I gave a minimal report (which was acknowledged) and signed clear. When the Roundtable net started, I checked in there too, and the NC graciously invited me to take a turn at the discussion. I gave a short description of my situation, which was understood with difficulty (my "fist" was incredibly awful, and I sent each word twice to improve the likelihood of a successful guess, er, copy). It was slow-going, and when one fellow wanted to know details about power levels, etc., I decided that I didn't want to subject the entire net to that (5 minutes is novelty; after that comes boredom or frustration at having to wait for this long transmission that you can't understand), so I simply said "NO THX" and signed. Next week, when I have my voice back, I'll share the full story with them. I was quite impressed at the skill of the guys (one in particular) who were able to pull intelligence out of my mangled transmissions, and was elated at my success.

Back to VHF

With the primary mission complete, it was time to continue the secondary mission of surveying repeaters. I got some help dropping the wire, hanging the antenna from my "sky hook", and hoisting it back in the air (while having someone hold onto the tuner so I didn't yank it off the table). It needed to be way too tight to leave it attached to the equipment, so we pulled off and I tied it off to a tree (gaining a tiny bit more height in the process). I tuned around and, not surprisingly, saw only a slight (and not statistically significant) improvement in signals -- until I hit Timberline. It came back a good 40dB over S9! I scratched my head, knowing that the antenna couldn't possibly offer that much of an improvement anywhere, and thought I must've missed that repeater in my earlier testing. I was pretty thrilled to find such a solid link, knowing that the owner of the cabin would be that much more interested in becoming a ham with the promise of that easy mode of communication hanging out there.

Unfortunately, after I disassembled my station later that morning and tried it again from the car, I found that the signal was terrible; in fact, I couldn't even bring the repeater up most of the time until I drove out of camp and was back up on the main highway. I think we must've had a little temperature inversion in the Portland area, and I just happened to catch a rare but very nice tropospheric duct to Mt. Hood. sigh 'Tis a pity...

Repeaters that I was able to trigger from the site:

- 146.68 N7EI Scappoose

- 147.30 W7DG Woodland

- 146.98 W7EXH KGW Tower

- 147.04 K7RPT Sylvan

- 146.84 W7LT Larch Mtn

- 145.27 KJ7IY Timber?

- 145.31/147.14 W7EXH/W7AC (don't remember which) Skyline

- 146.76 W7BU Nicoli

(I originally added the above list as a comment, but comments aren't visible unless you click an individual article.)

In closing

Bottom line: a good antenna mounted high combined with a linear amp (or a *really* good antenna without an amp -- but a 17-element Yagi's not usually a good choice in the middle of a sometimes-snow-laden forest!) could give you a usable connection several repeaters. (Oddly enough, my best signal was from Scappoose!) Otherwise, HF is probably your best option. A good well-grounded vertical might give you okay local coverage. A side note in this regard: KC7MRM in Kalama was unable to hear me during the net (though my tone might have been too high for his hearing) and his signal was fairly weak to me, while virtually everyone else on the net (besides K7ECW in Longview, who was also a little week) was very strong; That's not too unusual on these nets; I think they were in a fairly small "skip zone" that morning and my ground wave was very poor, while everyone else was just far enough away that they were able to catch a solid bounce near the MUF (or MUA - Maximum Usable Angle, if you prefer). All very educational, and a fine exercise in field operation and making the best of a tough situation!

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