Sunday, July 27, 2014

Sometimes newer is better!

You know when ones gets to be of a certain age, there is a tendency to think that the things we had back in the day were better than the new fangled versions that we have today. I’ve been guilty of that kind of thinking a lot. But in reality, the way things are today have some good points to them as well. They are just different and sometimes the decision has to be made to give up something in order to get something else.

For example, in past episodes of this blog, I have raved time and time again about how good those old tube type AM radio transmitters sounded. I’ve said that nothing can compare to that warm, rich sound that has been run through red hot tubes across the ether and into your radio receiver. I still feel that is the case, but achieving that sound came at a price; a price measured in sweat, hard work and dollars.

Back in the day, the average 1,000 watt AM radio transmitter was a little bigger than the refrigerator of the day, gobbled up power at a prodigious rate and was finicky enough to require almost daily attention from a broadcast engineer trained in the intricacies of audio and radio frequency current (RF) management. They had to be closely monitored by the operator on duty, in many cases the DJ spinning the records, who had to take a series of readings every half hour and make adjustments when necessary to keep the station’s signal within licensed parameters.

If you were unlucky enough to be running a higher powered directional AM station, you were saddled with even more readings every half hour to make sure that the tuning on the antennas had not drifted. Now there were currents and phases for all the antennas to be dutifully noted and logged. Each week, the chief operator had to drive a circle several miles wide around the antenna field and measure the field intensity of the “nulls” in the station’s RF pattern to make sure they were where they were supposed to be. If the pattern was “off” then came the painstaking task of “tweaking” the controls of the phasor that split the signal from the transmitter output to the towers. The bottom line was that because of the complexity of the transmitters plus the presence of all the tube electronics, turntables, cart machines and recorders, it took at least one and in many cases two engineers to maintain a single AM radio station.

Today, that refrigerator sized 1,000 watt AM transmitter is now the size of an industrial microwave oven and probably requires less power than the cooker. It is controlled by a micro-processor that can automatically make adjustments to account for variances in the power coming from the electric company, the transmission line and the antenna itself. It takes these readings continuously and keeps the station on the straight and narrow. It automatically raises and lowers the power and if necessarily switches the antenna pattern at sunrise and sundown if the station is a directional one. It also keeps the transmitter log and sends a text message or an e-mail to the chief operator if something is wrong. Many of these new transmitters no longer have tubes in them but are completely driven by solid state modules stacked in parallel. If one of these modules fails, the transmitter keeps going at a lower power and lets the operator know that it is time to pull that module out and replace or repair it.

So, instead of daily trips to the transmitter site the engineer spends an hour or so each week, checking everything out to make sure the transmitter can keep itself going. Gone are the half hour readings for the operator on duty, and the weekly field intensity measurements. These computerized wonders are so stable, that the FCC eliminated those rules a long time ago. There was a human cost to this. As station ownership migrated from the “Mom and Pop” ownership prevalent in the 60s to the current “Corporate Cluster” model of today, the need for a FCC licensed broadcast engineer or two for each station morphed into a single unlicensed chief operator for as many as 10 stations in the cluster. A lot of good broadcast engineers who did not make the transitions to consulting engineers left the business entirely.

The silver lining in this technical change is that for the few that are still locally owned and operated, the relaxation of the rules made them more affordable and the bottom lines of their ledgers were more likely to be written in black, not red ink. Now if the recent trend of corporations selling off stations to local entrepreneurs continues it could happen that we could see a revitalization of local radio broadcasting and that would be a good thing! I’ll give up some warmth and richness for that! Oh MY!

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