‘Wet Paint’ Controls the Crowd
Project engineer and
consultant Tom Osenkowsky recently was called in to troubleshoot a Harris
FM3.5K transmitter. It was off the air and multiple front-panel fault LEDs were
illuminated. The numerous faults made no sense.
Tracing the path through the
transmitter to the controller connections on terminal board E2, Tom found several
Fig. 1: The E2 terminal block in the FM3.5
transmitter is soldered to a board that interfaces to a ribbon connector jack.
Fig. 2: Closeup of the pins where
they pass through the board and are soldered on the bottom.
Fig. 1 shows the E2 terminal block and
the terminal board pins that solder to a board below the terminal block. A
close-up of the intermittent solder contacts is shown in Fig. 2.
Tom theorizes that because the block is
in proximity to the blower motor, constant vibration may have caused the solder
connections to become brittle and the pins intermittent. In any event, Tom
replaced the block and the problem was solved.
* * *
Cumulus Youngstown Market Chief Wes
Boyd comes up with great tips and videos to share.
Fellow ham Tedd Mirgliotta, KB8NW, found a unique YouTube
video that we’ll call, “No key?No
problem!” He passed it on to Wes.
You’ll find the link at Radio World’s
new links page for this issue. Go to radioworld.com/Mar-28-2012.
* * *
Speaking of editors: Former Editor in Chief
of Radio World International T. Carter Ross attended the annual meeting of the National Asphalt
Pavement Association. He noticed something Workbench
readers could use.
Fig. 3: A ‘Wet Paint’ sign keeps listeners away
from your risers. Use the Radio World link to download and print your own
videographers found what seems to be a dead-simple solution to the problem of people
climbing on a riser where a camera was positioned: Wet Paint signs.
could keep people from trying to sit on your stage or risers at a remote, where
talent and equipment might be in close proximity to a crowd. It’s a
subtle yet effective way to discourage people from getting too close. It works
best if the surface is clean enough to look like it was freshly painted. The
videographer told Carter that if signs weren’t enough
to discourage people, he had on occasion spilled a little water to
add to the effect.
included a link to a downloadable, printable “wet paint” PDF. We’ve saved it
for you at the Radio World links page: radioworld.com/Mar-28-2012.
* * *
It’s been a long time since I talked with John T. M. Lyles, an engineer
at Los Alamos. John and I worked together at Delta Electronics; he then went on
to design transmitters at Broadcast Electronics, prior to joining the Los
Alamos Laboratory. John still stays in touch with broadcasting through the
pages of Radio World.
our Workbench article “Does Your
Outpost Have the Basics,” we mentioned changing out foods you have in storage
at remote sites.
John has found that Mountain House freeze-dried meals, sold at Wal-Mart
and at many outdoors shops, are indispensable for camping or preparing for the
unknown. They’re lightweight and require only a spoon and hot water.
Best of all, they have a long shelf life — over five years— and can be eaten from the pouch. They
have a variety of selections, and are not like the old Meals Ready to Eat (MRE)
that the military provides. They also have enough seasoning to be tasty. You
can find the selection atwww.mountainhouse.com.
Need hot water? A small camping gas stove such as those made by Snow
Peak or MSR can heat your stored water. Search Amazon. Remember to provide your
future self a pot and lid too. If you’re going to be stuck at a site, you might
as well have a good meal.
John wrapped up his note telling
about his work completing the design and testing of a new pulsed RF amplifier
prototype for Los Alamos. This will be used for particle accelerators. It is
operating 24/7 at about 2 Megawatts peak power, and 200 kW average power. It’s
in life testing right now, at 1,600 hours and running. The RF output is at 201
MHz, which is about the middle of the old TV Channel 11.
Production is next, followed by the installation of a pair of these
beasts combined at each accelerator cavity over the next four years. They’ll
install a pair each year. John works with a crew of engineers and techs that
includes a couple of guys from Continental Electronics who joined him a few
years ago. John’s hosted a number of visitors, too. It’s definitely the place
to be for high-power RF!
Contribute to Workbench!You’ll help your fellow engineers, and qualify for SBE recertification
credit. Send Workbench tips to email@example.com. Fax to (603) 472-4944.
Author John Bisset has spent 43 years in the broadcasting industry, and
is still learning! He is SBE Certified, and is a past recipient of the SBE’s
Educator of the Year Award.