(click thumbnail)Fig. 1Here’s a column you’ll want to cut out and give to your friends and family as they wrap up their holiday shopping. Maybe they’ll take the hint!
Chris Kelly, CE at the Salisbury, Md., Clear Channel cluster, has organized all of his small parts in metal and plastic cases, as seen in Fig. 1.
Heading to the transmitter site, or perhaps a remote site? Take the Plano mini satchel, which combines several smaller plastic drawers in a canvas case. The mini satchel fits behind your truck seat or in the trunk and can be loaded with a variety of plugs, connectors and lugs. The case lids fit snugly, so even small components won’t mix from one compartment to the other.
. . .
(click thumbnail)Fig. 2We’ve talked about the benefits of infra-red inspections. Mike Gilbert, chief at Multicultural’s KARI(AM) in Blaine, Wash., picked up a portable Wahl infrared temperature monitor.
This hand-held device, pictured in Fig. 3, shoots a red beam to allow you to zero in on the part or object you are measuring. An LED display reads the temperature of the device you are measuring.
In the photo, Mike is measuring the temperature of a microprocessor. He has checked every physical connection in the station’s phasor and ACUs, as well as AC breaker connections and other electrical junctions.
(click thumbnail)Fig. 3
Are AM RF contactor contacts worn? The temperature monitor will alert you to a build-up of heat, before the contact surface fails, taking you off the air.
In an FM application, measuring the temperature of elbows or coax junctions can spot internal problems, without using Superman’s X-ray vision. Comparing the surface temperature of several elbows can give you a base-line number for normal operation. Periodic measurements will ensure your system is running properly.
Home Depot or similar large-scale hardware stores will stock items like the Wahl temperature monitor or the Plano cases and satchel.
Plan to spend a little time when you visit these stores; they are chock-full of engineering goodies at reasonable prices.
. . .
Looking for several useful add-ons for your remote control? Consider the Burk Temperature Module and Sensor. The device will accept up to four temperature probes (one is included with the module) .
If you have air-pressurized transmission line, the Phartronics Temperature Sensor Interface is a must. This module provides a linear DC voltage proportional to the gas pressure, and can be easily T’d into your existing line, as shown in Fig. 4.
. . .
(click thumbnail)Fig. 4
Phone accessories make good gifts.
Around the transmitter building, a long telephone cord, one that will reach to the transmitter should you need to talk to the factory to troubleshoot a problem, is helpful. A spare telephone cord is a good idea; they do get frayed.
Does your telephone have a mute switch? Consider installing one, because it will block background noise as you discuss your problem with a factory technician.
If you have a traditional telephone, find one of those "confidencer" noise-canceling handset mikes. It drops into the handset, and dramatically reduces background noise as you talk. Check the next Hamfest for one of these.
Speaking of telephones, how about adding call-waiting on the transmitter phone line? If you’re on the phone and that service technician is trying to reach you, you won’t miss the call.
I’ve spoken to some engineers who have used cordless phones, but many are plagued with RFI, so choose wisely. Another consideration is the cordless battery. A phone left in place with a constant trickle charge will eventually kill the battery. Better plan on a spare battery, just to be sure.
Glenn Foldessy of WOAC(TV), Channel 67 in Canton, uses a $100 V-Tek cordless phone with great success. Try Model VT-9000, a 900MHz phone that works great, even in front of 104 kW of 789.25 MHz visual power.
Glenn has used this cordless phone at many of his clients’ AM and FM sites. He can describe a part or problem accurately without having to write it down – a real timesaver.
. . .
With winter upon us, make sure your transmitter site has a shovel, some bottled water, some chocolate or protein bars, and a can or two of canned spaghetti or even a couple of jars of baby food on the shelf – just in case you get stranded.
Submissions for this column are encouraged, and qualify for SBE recertification credit. Fax your submission to (703) 323-8044, or send e-mail firstname.lastname@example.org