Carbon Monoxide Detector Goes Off

Last week, I finally had my HF vertical antenna up and was able to lay 16 ground radials, as best as I could. So far, everything seems to be OK. I have been hearing stations quite well, particularly on 40m (7 MHz) in the evenings. Overall, propagation had been bad from this side of the world, at least, so I'm not as concerned. For the past few days, I've just been scanning the bands and had been listening, but have not made an effort to contact anyone. Hearing stations was one thing. Being heard was another. That would be the ultimate test of my station.

I don't want to bore you with a lot of ham radio terminologies and gobbledegook, so I'll try to keep it at a minimum. And I'll try to make it as simple and as easy to understand as possible.

If you are not familiar, HF (high frequency, typically, below 30.0 MHz) communication uses the atmosphere to "bounce" off signals from one station to the other. The distance between the 2 stations can be in thousands of miles. On a good day, it can be anywhere in the world. For shorter distances, there is what is called a line-of-sight communication for VHF (very high frequency, 30 to 300 MHz) and UHF (ultra high frequency, above 300 MHz). Both VHF & UHF require the 2 contacting stations to "see" each other to establish communication. As a general rule, the lower the frequency, the farther the signal goes.

To help you understand these concepts, just imagine your typical FM and AM radio stations. If you like "old school" music, particularly the 1980s, you'd probably be listening to 98.1 KISS FM. This is an FM station in the SF Bay Area that transmits its signal on 98.1 MHz. If you drive further out of the Bay Area, say head towards Monterey or Carmel, the signal will no longer be as strong. As you drive further out, you may not hear it anymore. And this distance, point to point (not driving distance) is much less than 100 miles. On the other hand, if you listen to KGO 810 on AM, they transmit on 810 KHz (or 0.810 MHz). At the same distance or even further, you can still hear KGO loud and clear. As our general rule goes, the lower the frequency, the farther the signal goes. And goes for 2-way radio communication.

So, why did my carbon monoxide alarm go off? Let me explain....

After dinner last night, I turned my radio on and heard a group of Filipino hams in Washington state and California having a nice roundtable conversation on 40m (7 Mhz). Propagation was pretty good and most of their signals were pretty strong (in other words, LOUD). I decided to join in. I made the necessary adjustments to my equipment, and off I went. I stepped on my foot switch (which triggered my microphone) and blurted out my callsign, "NW6J".

Carbon Monoxide Alarm

I was heard on my first call. Barely into my response back, I heard a high-pitched beeping sound. Crap !!! By keying my microphone (and radio) and with 100 watts of power, I triggered something else in the house. It was an alarm. Probably the smoke alarm. It seemed like the station who acknowledge my call was having some difficulty understanding me. Between him and the beeping sound, I had to cut my conversation abruptly so I can check what was going off.

When I stepped out of the (radio) room (or ham shack, as we would like to call it), the beeping sound stopped. Whew!!! A sigh of relief. Even if the beeping stopped, I knew that it was only temporary, and that it would go off again once I transmitted. I reduced the power on the radio and went back on the air with 50 watts. As soon as I keyed the microphone, the alarm went off again. Holy crap !!! What's going on??? I ran out room, approached the smoke detectors and listened. It wasn't them. Wrong device. The beeping continued. I followed the direction of the beeps, which brought me to the carbon monoxide alarm that was plugged to the wall outlet in the dining room. Bingo!!! I unplugged the alarm and took out the battery. Then it stopped.

I called my son, James, and asked him to observe. I told him to go outside the house, stand by the driveway and see if anything unusual happened to any of our neighbors. I've heard of horror stories about RFI (radio frequency interference), like garage doors opening, lamps turning on/off, and water-sprinklers turning on, to name a few. I also asked James to check if our TV made any buzzing sound or the picture shook or if my voice was coming out of the TV, or if our lights flickered, every time I transmitted. Luckily, it didn't. And so far, nothing from the neighbors either -- at least, not last night.

With the alarm unplugged and the assurance that I have not (yet) cause any disruption to my neighbors and within my own house. I went back on the air and continued with the roundtable conversation. The other stations I was talking to was so kind enough to provide feedback on my audio (how I sounded from their end). After I few adjustment, everything sounded great.

Looking forward to spending more time on the air, and here's hoping that nothing else happens.........to anyone.