Wednesday, January 24, 2018

Slight Radio Mod

I was told that it sounded like I was talking through a tin can when using the little dual-band HT radio. I took apart the microphone and discovered that the microphone was behind a tiny pinhole. I drilled the hole out to 1/16" which is about five times the diameter. The hole was literally the size of a pin. Problem resolved. I suspect that the tiny hole was to prevent overdriving the microphone.

The built-in microphone on the HT radio had a similar tiny pinhole over the microphone so I proceeded to disassemble the radio case and significantly enlarge the hole to 1/16". I wasn't sure how close the actual microphone was to the case so disassembly was the only way to be sure that I didn't accidentally drill into the microphone. I had assumed that my signal was just poor and it was one of those cheap Chinese made radios that many in the ham radio community don't care for. But for less than ½ the cost of a "name brand" radio. I had originally ordered the hand-held microphone accessory for the HT due to the reported poor sound quality but it didn't resolve the problem. Disassembly, drilling, and reassembly took maybe ten minutes.

I had posted about this earlier but hadn't been tracking the progress. I thought some may find this interesting. Right now, the difference between magnetic north and true north is pretty small no matter where in the world you are. Alaska is about the 11 o'clock position. I think that the movement of magnetic north is significant but I'm shocked that there has been no mention in the popular press. I had first heard about this in EOS, an AGU publication. Is this an unpopular message or is it just not newsworthy?

Monday Morning Update - I found a bunch of articles that bring up climate change as the most probable reason for the poles moving. So I guess it's in the "unpopular message to some" category.


  1. Were the articles linking movement of the magnetic pole to climate change posted on the Onion? I remember from the geology courses I took back in the day that the so-called "polar wander" was due to movements in the core of the earth in relation to the crust; climate would have no effect. According to Wikipedia "True polar wander represents the shift in the geographical poles relative to Earth’s surface, after accounting for the motion of the tectonic plates. This motion is caused by the rearrangement of the mantle and the crust in order to align the maximum inertia with the current rotation axis."
    I also remember reading an article a while back in the Smithsonian Air & Space magazine that talked about flying B-29's over the pole to check on the Russkies during the 50's and how they'd lose all their compass nav-aids whenever they were close to the magnetic pole. It apparently was a big deal before the global GPS system.
    Have a nice day! BJ

    1. No, there were articles from other non-mainstream publications. Most articles didn't speculate on the cause but more on speculating on why the movement was accelerating. And, yes, I do remember those geology classes but I also remember when learning to fly, having to look at the maps and adjust the compass for magnetic deviation. Since most rely on sat-nav these days, I suspect that it really isn't too much of an issue as long as you were aware of it.

    2. BTW, thank you BJ for reading and commenting!

    3. Thanks, I seldom comment anymore as some take them the wrong way or simply ignore it, so seems better to usually not bother. But you seem like a someone who'd appreciate it. Anyway, I've followed your blog since you appeared in the News Miner and often thought of heading to the college coffee shop, since I knew George, Steve and Brett back in the day. Maybe next summer? Thanks again! BJ