— Stephen S. Lockwood is a senior professional engineer and a
partner with Hatfield & Dawson Consulting Engineers; his
communications career has spanned more than 28 years. He works on
both AM and FM engineering projects but specializes in AM, and is
slated to take part in a session at the upcoming Radio Show about AM
technical solutions to revitalize the senior band.
on a Qatar Coast Guard tower at Al Aish Qatar. He was helping with
electromagnetic compatibility issues caused by proximity to a 2 MW
medium-wave station about a mile away. The AM antenna system was
designed by duTreil Lundin & Rackley /Hatfield & Dawson Joint
Venture and constructed by Harris Broadcast.
World News Editor/Washington Bureau Chief Leslie Stimson caught up
with him after he had returned from a quick trip to California to
help a client, a power plant under construction near an AM station.
What’s going on in California?
If you put up a construction crane near AM stations, the end of it
will give you a pretty good arc. That tends to make the people
working around it somewhat upset. So we’ve been working with a
power plant from the beginning — helping them work with the AM
stations, and also when they’ve had other problems along the way
because they’re building right next to the AM station where the
field is 10 Volts per meter. There are certain electronics problems
that you’d expect to have with interference issues.
was buzzing down there yesterday because they’re getting ready to
finally start spinning the turbines and discovered that they had
instrumentation that wasn’t performing the way they thought it
ought to. So I went down and performed what Benjamin [Dawson, the
company president] calls “consoling engineering.” We patted them
on the head and said “We can fix this,” and we showed them the
way to solve these problems.
Broadcasters have pulled back from station facility projects during
I think broadcast has probably been traditionally 60 or 70 percent of
our practice. One of things that Benjamin has done over the years is
diversify this practice. We have two of our engineers who do nothing
but public safety land mobile systems. That diversification has
helped us survive the recent unpleasantness.
do land mobile engineering for public safety systems large and small,
as well as for transit agencies, busses and trains. We also do
engineering for difficult and complex SCADA systems for utilities. We
are also very experienced in in-building radio system design, ranging
from jails to the NPR parking garage.
always seem to have some international work we’re usually doing
with the joint venture with Ron Rackley and Ben. [A joint venture
formed by duTreil, Lundin & Rackley and Hatfield & Dawson
conducts engineering work for the U.S. government’s International
Broadcasting Bureau. Since its inception, the Joint Venture has
worked on high-power antenna systems that operate on LF (30-300 kHz),
MW (300-3,000 kHz), and HF (3 MHz -30 MHz), not only for the U.S.
government but for other governments and other providers of
high-power radio services worldwide.]
we do work offshore, especially if it’s in the medium-wave area, we
typically do that as a joint venture so we almost always have some
project in the Middle East where somebody’s putting in a couple
hundred-kilowatt transmitters or designing antenna systems. Those odd
projects have really helped us survive. But the nice thing is the
phone’s ringing again on the broadcast side. We’re starting to
see some additional work there.
In our March 27 issue, Ron Rackley and Ben Dawson made several
technical suggestions to the FCC to fix AM; and the question of AM’s
future is in prominent industry debate. What should the commission
do? Should it eliminate minimum antenna requirements or city of
license coverage requirements, for example?
All of these suggestions that Ron and Ben had, those are things that
we’ve been talking about here for years. There are many rules that
the AM service is saddled with that go back to previous models of
broadcasting where we were still trying to protect the Class A
stations. I love the Class A stations, they’re wonderful history.
And it’s really cool to have a radio station that covers five
states at night. …
the protection of that nighttime contour on adjacent channels … and
you look at minimum efficiency and these kinds of rules that came up
through the years, were really efforts to try to protect the Class A
stations and they were also, more about the restraint of trade during
those times than any good engineering practices. They were just
trying to keep the other broadcasters out and to keep the value of
the existing facilities as high as they possibly [could]. With that
said, I think that looking at all of these rules, there’s probably
a few others we can add, but probably not as important as the ones
that Ron and Ben settled on. …
Lockwood is a partner at Hatfield & Dawson Consulting Engineers.
While he works on both AM and FM engineering projects, he specializes
in AM and is slated to speak at the upcoming Radio Show.
look at these rules and loosening them up and giving some
flexibility, I think that gives the owners some ability to make some
facility improvements and increase their coverage where that makes
sense to them but puts them more in control of their license. And it
puts them in a situation where they can make decisions based on
financial and engineering considerations and coverage considerations
versus historical political reasons.
Do you have any hope anything’s going to change?
I’m cautiously optimistic. Many of these rules, I think, 10 years
ago if you had wanted to change these rules there were certain
[radio] group owners that were still trying to hang onto some of
these things to protect their assets, or felt that they protected
What about analog AM, should it be sunsetted in favor of a digital
In general terms, I like that concept, but I look at all of the
proposals out there…when I first saw that Channel 5 and 6
discussion I thought it was a neat idea if the world was a perfect
world, that’d be great. But once again with those kind of changes,
that wholesale change, there’s a real problem because it’s the
haves vs. the have-nots. …
political side of who gets and who doesn’t get is, in my view, the
biggest part of the problem. I don’t know how we get through that
side of it and keep most everyone happy.
You mentioned diversification. Are you involved in cases where a
radio station leases tower space to a wireless company?
We’ve done a lot of that kind of work at all power levels and
helped folks through that process. Sometimes it makes sense.
Sometimes it doesn’t. One of the things that we have come to
appreciate is that it can be done, it just needs to have some
thoughtful engineering approach to it. It is often so out of the box
for the cellular companies and the types of firms that they hire to
do the rigging and installation work that a lot of those folks make
mistakes along the way, so it takes a lot of handholding. But once
you’re through that process, it can write a nice check [for the
station], and continually write that check. It makes quite a
difference to some of the facilities that we’ve helped through that
process, where, essentially they’ve got enough money coming in off
the rental to pay for half of an engineer.
What does the firm do on the public safety and mobile side?
[W]e have work from the cellular companies. Often there’ll be
interference disputes between parties and we will go help mitigate
those and /or even determine if any of its real. We’ve helped
landlords negotiate leases.
the Pacific Northwest, we have the 100 percent employment program for
consulting engineers, and that is, a lot of jurisdictions require a
PE stamp on an RF exposure study for a cell site, which is one of
those things that we continue to do.
What about instances where the station has signed the contract, and
the engineer walks into the transmitter site later to find the cell
people have created a mess. Do you have clients who run into that?
Oh yes, and it’s interesting from company to company. The cell
companies have gotten so that the companies themselves really have no
employees, and they’re all contractors of contractors. There’s no
continuity in their site installation or their maintenance.
of the things we found particularly funny is with AM towers, you have
a cell company that will issue an edict and they say “On all of our
sites we will have these particular features.”
few years ago one of the cell companies in Alaska had problems with
ice falling off the tower and damaging the transmission lines, so
they said, “All of our sites will have ice bridges cover the site.”
They did that at the AM site of one of our Alaska clients. They went
and got time with the owner, turned the AM stations off and went and
installed their ice bridge and grounded out the tower.
You said things were beginning to turn around on the broadcast side.
It sounds like stations are spending money on engineering projects
again. Are they building new or upgrading? What are some typical AM
and FM projects you’re doing lately?
The biggest projects that we have going on right now have been sort
of bubbling along for awhile. They’re situations where facilities
have been on an STA and/or there’s some sort of move or something
like that that has been going along and they’ve just not been
funded. Now that things are loosening up a bit we’re getting “go’s”
on a number of those projects. But they all are projects that 10
years ago would have been done instantly because of the concern about
compliance with regulations and getting off STAs and things like
that, depending on the owner, of course.
the FM side we’re starting to see some movement, some places that
have had construction permits loafing along for awhile. People have
tried to keep them alive but they didn’t want to spend any money on
them. We’re finally seeing some of those either bought or sold and
then implemented. In multiple user sites, that usually requires
someone else to move, so there’s some system integration issues
that need to be taken care of. We’ve probably got half a dozen of
those happening right now.
What about HD Radio on the FM side. Are people implementing the power
We have some. I think the [FMs] that were able to do that by walking
over and getting their little green screwdriver out and cranking
things up did that right away. We had a few folks, and still do, that
are contemplating it but that requires capital expenses. …
the AM side, which is where I’ve spent more time on it, I think
that there are a lot of folks who went through the process of
installation and have shut it down. My observation of the AM side is
I don’t think it really got a fair shake. I say this from looking
at all of the things that needed to be done to the AM antennas that
we had talked about at a number of NABs over the years, we noticed
even at several high-profile stations, that these things were not
Meaning the antennas weren’t optimized for HD because they didn’t
have the money?
It’s either they didn’t have money or they didn’t understand
the process. … These are some high-profile cases where I went and
visited the facilities on other business and looked at what the
transmitter was seeing and it was not optimized for AM and not really
optimized for the transmitter.
with our experience with the CPB grant for the conversion of the AM
projects, there were a number of those that got their grant and went
and did it and just kind of laughed off the antenna side of it. If
you don’t take care of the antenna side on AM, it just doesn’t
work. We’ve watched people spend tens of thousands of dollars on
the HD conversion and then get to the antenna system, and throw their
hands up in the air and not do anything about it.
What does the audio sound like when that happens?
You get digital in your analog and you get analog in your digital. So
you hear the bacon frying in the background. That’s where the
digital’s getting in the analog. You can hear the bacon frying in
the background, the hissing, the noise …
From the host station, right?
Yes, it’s interfering with the host station. And the other side of
it is, if the analog gets in the digital, the signal doesn’t go as
far. The digital signal is not decodable all the way out to 2
millivolts or something like that. The problem is, you’ve put in a
system but you haven’t optimized it and if you don’t take care of
that antenna component, it just doesn’t work.
Are you doing more AM or FM projects right now?
I typically do more AM projects and I get the weird projects, which I
like. We do work for all sorts of governments all over the world.
We’ve had modeling projects for foreign governments on Navy-type
installations. We’ve had situations where wind farms have come in
near AM stations so we’ve done a little modeling on those. A couple
times a year we seem to have projects that involve power companies
putting new transmission lines near AM stations. We’ve worked on
all sides of that. Often it seems the last few years we’ve ended up
working for the utilities to help them through the process and then
work with the broadcaster and make sure that they understand that the
utility understands the problem and this is what they’re going to
do to solve it.
To make sure the utility doesn’t interfere with the AM station?
Right. It’s another one of those situations where, like cell towers
near a facility, if you build additional structures that are somewhat
similar to the height of the AM towers nearby, it can really distort
their pattern and problems can occur. Thoughtful engineering needs to
accompany those kinds of installations.
How did you get into radio engineering?
I come from a line of engineers, my grandfathers and father were all
engineers. My father was a mechanical engineer and he was interested
in radio. Both my grandfathers were mechanical engineers as well.
When I was in junior high I had a neighbor who was also a teacher at
my junior high who was a radio engineer and taught history and
electronics. His name was Dr. Tom Gruis. As members of the radio
club, he gave us lots of tours of radio facilities around Des Moines,
Iowa. I got my Third Class license fairly early. My first Class
license I got just after I got out of high school.
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