Hum, continued
Apr. 3rd, 2011 07:16 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
necturusThe left and right channels of this morning's broadcast from Memorial Church were out of phase. Yesterday I took care to make sure all my connections were right, but it didn't occur to me that the cable from the church to the station might contain a phase reverse, which it does. I arrived midway through the broadcast and reversed the polarity of the right channel, and that cured the problem.
After the broadcast, we tried inserting a second set of transformers at the church end to get rid of the hum, but it had no effect.
However, it turned out that one of the two channels coming from the church has another line connected in parallel that goes to Widener Library, where it was plugged into yet another line running from there to the station. When we unplugged that line, the hum went away. So, the Reverend Professor's memorial service Wednesday morning will air with no hum after all.
Meanwhile, Rhode Island called to say their FM never came on this morning, and New Hampshire left a message reporting a problem with the Yankees, but didn't answer the phone when I called back.
After the broadcast, we tried inserting a second set of transformers at the church end to get rid of the hum, but it had no effect.
However, it turned out that one of the two channels coming from the church has another line connected in parallel that goes to Widener Library, where it was plugged into yet another line running from there to the station. When we unplugged that line, the hum went away. So, the Reverend Professor's memorial service Wednesday morning will air with no hum after all.
Meanwhile, Rhode Island called to say their FM never came on this morning, and New Hampshire left a message reporting a problem with the Yankees, but didn't answer the phone when I called back.
