Our “new” 20kW transmitter at full power!

We have crossed another milestone in the upgrade of KOLU to 39,000 watts.  The 20,000 watt transmitter has been tested at full power and is working well!

Along the way, we have installed a wire tray that will carry wiring that sends signals to control and monitor the transmitter.  Although we had completed re-wiring of the high voltage section, we weren’t entirely satisfied since some wire was brittle and there was many wires that had extra length, so we dove back into it and “cleaned up” that wiring.

The transmitter came up well although there were a couple of “hitches” along the way.  Some was due to our unfamiliarity with the control system and a couple of indicator lights that were burnt out.  Together with a wiring error in the smaller “driver” tube circuit, we had a couple of challenges yet all was figured out and fixed.  The transmitter engineer that is helping us commented that this used transmitter is in excellent condition, with only a few minor problems that we have easily corrected.

As of this writing, the transmitter is still tuned to the frequency of its former owners.  All power that the transmitter generated was directed into our “dummy load”, making for a lot of heat in the building!

Our next step in the upgrade will be to tune the transmitter to 90.1 MHz.  After this, we will run full power through the antenna for a couple of hours to make sure all is well.  This is what the FCC (Federal Communications Commission) describes as “equipment testing”, which we are authorized to do.  We are not authorized to leave it on the air, as testing for safety from strong radio frequency fields must be done before we can apply for the license that will authorize us to transmit at the higher power.

We will schedule the testing shortly.  While this is being arranged, we will complete the wiring to remotely control and monitor the transmitter.  The completion of the test report and an electronically-filed application for license will allow us to immediately broadcast at 39,000 watts, which is known as “program testing”.

In case you are wondering how a 20,000 watt transmitter produces 39,000 watts in coverage, it has to do with what is known as “antenna gain”.  Our antenna has a gain of about 2, which enables us to “multiply” our power compared to an antenna without as much gain.

Praise the Lord, we believe we are a few short weeks from broadcasting on KOLU at 39,000 watts!