Longtime Engineer's Corner readers know that we've had, well, "issues" with the STL or "Studio/Transmitter Link" for our 88.1FM signal in Providence. The STL is what carries the audio from our studios in downtown Providence to the transmitter/tower at the Wheeler Farm in Seekonk.
Now a couple weeks ago we revealed that half of a new wireless microwave STL was installed, and that the other half would be installed soon. Today, we fired it up for the first time and the results were gratifyingly positive!
In many ways, this is an even bigger deal; 102.7 had a hefty vent fan system that could move a lot of air. Sure, if the air outside was hot, it means the air inside was hot, too. Usually you can't cool a room using outside air below about +10F degrees above outside air temps. So if it's 90F outside, it's 100 to 105F inside...ugh!
And at 88.1, we didn't really have even that. The transmitter site is an 8x10ft shed with a single 12 inch desk fan blowing air out one of the wall vents, and no insulation whatsoever on the walls or ceiling. Temps routinely broke 120F inside, even when it was only 70 to 80F outside.
The morning of April 30th saw several odd "dropouts" in the audio on 88.1FM, usually lasting 5 to 8 seconds each, happening as often as 2 or 3 times a minute, but more commonly once every 10 to 15 minutes.
There was also an odd "repeating audio" effect some people noticed, when the audio came back.
In light of ongoing issues with the Studio/Transmitter Link (STL) for WELH 88.1, we have implemented a new STL schema. If you heard a lot of odd audio dropouts on 88.1 today, that was the reason.
The good news is that we should have a pretty good temporary solution in place, and a solid path for a permanent solution is on the horizon (tentatively scheduled for mid-March). Best of all, I was able to put in a new(er) Orban Optimod 8100A audio processor to replace the less-capable Inovonics DAVID-III. There's a little sibilance still, so I need to tweak the settings. But overall the sound should be much louder, fuller, and more consistent.
UPDATE (Jan.10): Verizon sent a trio of techs today to examine the Digital Lines. They found a splice point on a pole near the Wheeler Farm end of the circuit where water had gotten past the weatherproofing. The splice was re-done, with fresh (and better) weatherproofing sealant applied, and a weather box placed around it.
That's likely the culprit here: the problems started during the snowstorm, so probably water got in there and expanded/contracted repeatedly as the water froze and melted. That expansion wreaks havoc with (relatively) fragile copper telco wiring.
As of 3pm we are back on our main STL. We've noticed the volume levels seemed to have changed somewhat with this repair, too, so we're still tweaking things.