Radio Furaha -- off the air!

Walking along the street behind our apartment we passed by the Synod Office of the Evangelical Lutheran Church of Tanzania, Iringa Diocese. We had no idea it was that close to where we were living. In that office complex is the studio for Radio Furaha FM 96.7 Mhz. This is a station that the Diocese office started a couple of years ago for education and evangelism in the Iringa area. See: http://www.radiofuraha.org.

When we stopped in the assistant manager, Amos, said that the manager was up at the transmitter site trying to determine why the transmitter was off the air. The site is a short drive up a rocky hill to a hilltop with many microwave (the way the country is linked together) and FM transmitter sites.

We found the Crown Transmitter system overheating and the power amp reducing to 130 watts (instead of its normal 2 kw). None of the fans were running. Not on the Crown PS2000 switching power supply nor on the Crown PA2000 FM amp...

After removing the tops of the power supply and amp, we found no obvious fault: all the fans worked on 24 VDC, all the fuses were good. It appeared that the fans ran thru a DB-9 connector from the power supply to the amp. Of course, we didn't have the manual, so trouble shooting was trace and guess. The technician guessed that a 5 pin regulator had something to do with the failure and unsoldered it. It of course had no markings so we packed the powers supply and amp down the hill to "Iringa Electronics"

Here is Protus, the Radio Furaha manger looking over the suspected circuit with the local satellite TV tech, who was a great help.

There the tech put the 5 terminal regulator back in the circuit and attempted to determine where its power came from. Eventually, they were able to trace the fault and as of 7 PM the transmitter was back on the air. With no back-up transmitter, this little radio station depends on this Crown unit. I don't know what I contributed to the effort, other than suggesting that since all of the fans were not running, it must be in the control of the fans and neither the fans, nor the power to the fans (which indicated just fine since the switching supply powered the amp for a few minutes until it overheated every time we turned it on).

A very interesting day which went nothing like expected, but I got to learn quite a bit about Crown amps and Radio Furaha. All of this done without ever refering to the Crown manual or giving them a call. Amazing!