The WKZE single-bay antenna is mounted on the left-hand tower.
WKZE single bay Shively 6810 antenna with Radome
The transmitter is a CCA FM3000DS, made new in April, 1970:
WKZE 98.1 MHz CCA FM3000DS transmitter
The CCA designs are dirt simple. Grounded grid, driven with an external solid state amplifier that is a modification.
WKZE CCA FM3000DS transmitter, 42 years onWKZE CCA transmitter name plate
As you can see, this transmitter was originally manufactured for WHVW-FM, which is now WCZX. The station has a large, mostly cult following throughout the mid Hudson valley. Even though it is a 3,000-watt class A station, its coverage carries far beyond its theoretical 60 dBu contour:
I found this on the floor at an old transmitter site:
Polyphaser IS-PT50HN-B DC block surge suppressor
Since it appears to be discarded, I ignored the dire warnings and opened it up to look inside:
Polyphaser IS-PT50HN-B DC block surge suppressor
This is is a DC blocked lightning surge suppressor designed for 890-980 MHz, 750 watts maximum. The two parallel wires represent a capacitor, coupling the radio to the antenna, the inductor acts as an RF block to the gas discharge tubes. The design is such that the inductor acts to block the normal in-use radio frequencies but will allow the 10-30 KHz lightning pulse to pass to the gas discharge tubes and thence to ground. The inductor and gas discharge tubes are on the antenna side of the unit. I measured these units with a DVM and they all appear to be good.
My only comment on this unit is that there is no effort to maintain the transmission line impedance. At the upper end of the UHF spectrum, this can lead to return loss and wasted power. For a receive application, it may not be so bad, but for a transmitter, I would rather use something else.
For lower VHF frequencies, something like this can be DIY fabricated with minimal expense and effort. The case must be bonded to the station ground.
This is a universal truism that can also be expressed as “Murphy’s Law.” I don’t rightly know how Murphy received credit for this, however, I chalk it up to either the luck of the Irish or the gift of self-promotion. Either way, that principle was demonstrated again with a 950 MHz STL link between Mt. Beacon and Peekskill, NY for WHUD.
I noticed, while doing some transmitter maintenance, the receive signal strength of the STL had dropped from 300 µV to 30 µV. That is an alarming development. Therefore, we scheduled a tower crew for the next day, not wanting to go off the air over the coming holiday, which would be a sure bet otherwise. Upon arrival, the tower crew noticed a strange thing in the STL transmission line at the base of the tower, which looked like some type of a splice. Truth be told, I have been associated with this station since 1999 and had never noticed the splice before. This STL system was installed in 1998 when the station’s studio moved from Peekskill to Beacon. I can say, of all the things that have gone wrong over the years, this STL system was always very reliable. Regardless of that, I quick check with a spectrum analyzer showed a 3 dB return loss at 137 feet (41.75 m), exactly the distance from the transmitter room to the base of the tower.
3 dB return loss, distance to fault 137 feet
A 3 dB return loss coincides exactly with the drop in received signal strength at the other end of the path. Thus, the tower crew took apart the splice and water poured out of it. I would estimate at least 4-6 ounces of water (180 ml), perhaps more.
7/8 coax cable splice connector, opened up
We then began to take in the details:
The 7/8 coax coming out of the building was Cablewave FLC78-50J
The 7/8 coax going up the tower was Andrew LDF4-50A
The splice connector was Andrew L45Z
The center conductor threaded connector did not fit properly into the Cablewave cable, it was too loose.
The cable was chaffing on a tower leg, about 50 feet above the splice because it was not properly secured to the tower
The 7/8 splice connector was missing an O ring on the backnut of the Cablewave cable
Thus, water ingress causes the high return loss. Problems with this system began immediately after Hurricane Irene, at the end of last August. We were able to make a temporary fix using two type N connectors of the proper manufacturer for each type of cable. The radio station returned to air just before noon, about 45 minutes after turn off. After the repair, the return loss dropped to about 20 dB, which is good.
The permanent fix is for the entire run of cable from the transmitter room to the STL antenna to be replaced. That type of line splice should have never been used on a 950 MHz STL, and it was certainly wrong to mix cable types with an Andrew connector. Those little details will always manifest themselves eventually.
We were notified that the WFAS-AM tower lights were out, thus, it was time to investigate. This problem was easy to find. Upon removing the waterproof cover on the tower light flasher box, I found this:
melted SSAC B-KON tower light flasher, damaged by lightning
As soon as loosened the screws on the cover, I smelled the unmistakable odor of burned electronics and plastic. I disconnected the flasher and covered the photocell, which turned the side markers on. Of course, the top flashing beacon was dark, therefore, it was time to report the outage to the FAA. The nationwide number to report tower light outages is (877) 487-6867. That number is for an automated system, however, eventually, it leads to a live person. Since the new reporting system was established, the only required information is the tower ASRN. From that information, the operator will access a database and have all the required information to issue a NOTAM. In the past, many questions were usually asked; what is the nearest airport, how far away is the airport, how tall is the obstruction, what is the position, etc? Therefore, things have become slightly easier than before.
Once the outage is reported and a NOTAM is issued, the tower owner generally has fifteen days to correct the problem.
