FM DX

warning: Creating default object from empty value in /home/campusac/public_html/blog/modules/taxonomy/taxonomy.module on line 1387.

Modifying my Yahama T-85 for Selectivity/Sensitivity

I modified my Yahama T-85. I replaced all the fm filters (not sure what they were exactly, as I'd replaced some of them before with narrower ones) with 150 khz ones (that I got from dxer Bill Ammons). So it now has five 150 khz filters.

The downside is that there isn't much difference between the four filter settings anymore (superwide, wide, narrow, and super-narrow). So changing filter width isn't fun anymore. Suprisingly it doesn't matter too much whether you are using two 150khz filters (super-wide) or five of them (super-narrow).

The advantage is that I think I gained several decibels of sensitivity (I think from replacing old yamaha filters - the new low-loss filters have a couple db less loss than the old ones, not sure when the new ones were introduced -- or it is possible that the gain is from using a narrower filter and thus being able to concentrate on amplifying the signal). Also now I get the strongest signal meter reading for all stations when I'm in super-narrow mode, without having any distortion (probably because Bill Ammons matches the filters), except for a couple stations that are over modulating. Previously, I'd get a stronger signals in super-wide mode, because the narrow filters had higher loss (and/or were misaligned).

An Ebay Adventure - Buying Something Electronic that Actually Became More Valuable

I spend a good bit of my spare money on electronics. Typically I buy things that lose between 5-50% of their value each year. For instance, until recently when the devaluation rate has slowed down, computers typically would lose 30-50% of their value per year. Other electronic devices that I own tend to break, quite often fatally. Currently the record-holder in life expectancy is my hot-air popcorn machine which I've had for 14 years. You have to know how to tilt it if you overload it, but otherwise it works fine.

So electronics are full of disappointment and guilt, because I don't like the idea that I'm destroying or rendering obsolete things that used to be state-of-the-art.

Improving FindRadio.us

I'm working on improving the Find Radio site.

The biggest improvement was for FM stations where I added FCC suggested coverage area maps. Pretty cool. For instance, you can see KUGS which I used to listen to when I lived in Vancouver. Note their directional beam pointing at Vancouver (probably an unintended consequence of aiming for the coast, where more people live, and trying to avoid mountains which block FM signals).

The FCC publishes coverage data in GIS format too. It's big (200mb).

Find Radio Stations

I'm creating a website to Find Radio Stations using the FCC database and a Google Maps interface. Pretty basic stuff so far, except the innovative use of Google Maps to show where stations are located.

And, where Google has good satellite data, you can actually see the antenna towers!

FM Dxing

FM E-Skip Season Starts
So it is summer and the FM Eskip season has begun! Several days ago I caught my first opening of the year. Normally the season lasts from around May 15 to August 15, and is best during the day-time with slight peaks around noon and 6pm. It lasted a little over two hours, unfortunately there was a lot of variation. Thus for perhaps 80% of the time, you couldn't hear anything. But stations would often fade in with strong signals for anywhere from 30 seconds to a couple minutes, and then everything would fade out.

Also, most of the time the MUF (maximum usable frequency) didn't get above 92 mhz - so it was hard to identify the non-commercial stations as they don't regularly identify themselves, and there are many more on each frequency.

Syndicate content