[Mike Rivers]

Scott Dorsey wrote:

Essentially first-come-first-served. Before using a frequency, you have
to listen on that frequency. If it's free, you can use it. If someone
else is using it, you have to look elsewhere.

Yes, this is the case when secondary users are sharing the channel among
themselves.

BUT, the primary user (traditionally a TV station) has precidence over
all the secondary users. You cannot go to the TV station and ask them
to shut down because they are interfering with your wireless, but the TV
station engineer can come to you and demand you shut down if you are
interfering with the primary licensee.

Understood, but the TV station isn't going to hop on to a frequency, use
it for four hours, and then go away. Chances are they'll be there when
you're setting up for the gig and they'll be there after you're gone.
You listen, you see that they're on the frequency that you planned to
use, and you look for another frequency.

The issue of secondary licensees having to share bandwidth is one of
the reasons why large events get professional frequency coordinators
whose job it is to make all of the different organizations at the event
play nicely together.

That's fine for the event, and no doubt necessary. But suppose a
corporation like Jak's client is putting on a business meeting at a
hotel in Atlantic City and there are four show theaters within RF range
of the hotel (perhaps one at the hotel itself) that are using wireless
mics. Presumably they've done their frequency coordination so they can
play nicely together, so I guess it's up to the traveling event's
frequency coordinator to find out who else is using wireless in that
area, what frequencies they're using, and what frequencies are free. I
suspect that there are some places where it can get mighty tight and
there's just not room for another 50 mics.

I seem to recall something about a beacon, which was intended to reserve a frequency

Hmm... 20 years ago this would have been illegal since it would have been
unattended operation. I'm not sure if it's legal or not now.

I don't believe it was ever implemented as a solution, but I'm pretty
sure it was proposed and considered.


--
If you e-mail me and it bounces, use your secret decoder ring and reach
me he
double-m-eleven-double-zero at yahoo -- I'm really Mike Rivers
)

[Don Pearce]

 Mike Rivers wrote:
Scott Dorsey wrote:

Essentially first-come-first-served. Before using a frequency, you
have to listen on that frequency. If it's free, you can use it. If
someone else is using it, you have to look elsewhere.

Yes, this is the case when secondary users are sharing the channel among
themselves.

BUT, the primary user (traditionally a TV station) has precidence over
all the secondary users. You cannot go to the TV station and ask them
to shut down because they are interfering with your wireless, but the TV
station engineer can come to you and demand you shut down if you are
interfering with the primary licensee.

Understood, but the TV station isn't going to hop on to a frequency, use
it for four hours, and then go away. Chances are they'll be there when
you're setting up for the gig and they'll be there after you're gone.
You listen, you see that they're on the frequency that you planned to
use, and you look for another frequency.

The issue of secondary licensees having to share bandwidth is one of
the reasons why large events get professional frequency coordinators
whose job it is to make all of the different organizations at the event
play nicely together.

That's fine for the event, and no doubt necessary. But suppose a
corporation like Jak's client is putting on a business meeting at a
hotel in Atlantic City and there are four show theaters within RF range
of the hotel (perhaps one at the hotel itself) that are using wireless
mics. Presumably they've done their frequency coordination so they can
play nicely together, so I guess it's up to the traveling event's
frequency coordinator to find out who else is using wireless in that
area, what frequencies they're using, and what frequencies are free. I
suspect that there are some places where it can get mighty tight and
there's just not room for another 50 mics.

I seem to recall something about a beacon, which was intended to
reserve a frequency

Hmm... 20 years ago this would have been illegal since it would have been
unattended operation. I'm not sure if it's legal or not now.

I don't believe it was ever implemented as a solution, but I'm pretty
sure it was proposed and considered.



The big problem here is that when a radio mic causes interference to a
tv station, it isn't the station itself which notices, but the viewers.
These viewers will typically be non-technical, living in marginal signal
strength areas and are probably accustomed to odd things happening to
their pictures. Notification of a problem will therefore be sporadic and
unreliable. Certainly for a one-off gig it will be over long before any
kind of investigation will be started. Here in the UK we have PMSE
(programme making and special events) which co-ordinates the use of
radio mics and ensures minimised interference.

d

[Scott Dorsey]

Philip Perkins wrote:

Stay tuned, Scott. There are a lot more wireless users than the FCC
thinks. I have no doubt that people like me will continue to be
variously hosed by all this, but also think that things are not going
to exactly turn out as the big tech biz types think they will either.
Ownership, of property or anything else does not preclude public input
into how you use your property.

In the seventies, you could get anything you wanted from the FCC if you
could demonstrate a benefit to the public and you could demonstrate
technical competence. Today you can get anything you want from the FCC
if you pay enough money.

It's a different world altogether, but the current scheme can work for
you if you understand the rules.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[jakdedert]

Mike Rivers wrote:
jakdedert wrote:

We do hire all the gear; but it's still my problem when/if it doesn't
work.

OK, so it's your responsibility to find a vendor who has gear to rent
that will work. Your job may be more difficult during the transition
period, but those vendors who want to stay in business will eventually
make the investment they need in order to do so, whether it's in
modifications or new equipment. This will probably result in a price
increase to you, which you pass on to the company that hires you.
There's not much you can do about that other than to try to find a
different rental company that you trust. But in your position,
confidence is worth paying for.

Maybe I'm being a bit long-winded; but somewhere in there I tried to
make it clear that the gear I get, is the gear I get. If something goes
wrong, I can have it changed out, but I have no control over the vendor.
I'm just expected to make it work unless I need to do that. Then, the
vendor is in Chicago, and I'm in Vegas, Atlanta, Hershey, Uncasville CT....

That said, the company we use is very good; but the circumstances of the
gig, along with new regulations, make their--and my--job very difficult.

All that's still beside the point; which is that apparently the FCC has
no idea of the scope of the issue (although that baffles me, as all the
units are type-accepted). Mine is a fairly minor show in the grand
scheme...not all that unusual even for my company or even for this
particular client. Multiply my 52 channels by the number of venues (all
mid to high level convention hotels--hundreds), and the number of shows
weekly in those venues, just to get an inkling. In my research, I've
read that some Broadway shows use at least this many mics or more.

All that said, this is probably off-topic for this group, especially as
it's apparent most of you don't really have much perspective on the
number of mics out there in daily usage...conservatively I'd say
hundreds of thousands nationally. It's not really a recording issue,
which seems to be where the majority of the readers practice.

One caveat is that the fourth mic in every room is a spare.
The client actually spec'd three per; which doesn't physically work
out all that well for rack-mounted RF receivers. It made more sense
to just rack up the extra receiver than to separate their half-space
units. That said, the fourth one must work...and my experience with
this client is that it will get used--for the same reason Hillary
climbed Mt. Everest....

This should go into your proposal - not just passively, but state that
you will be providing four mics based on your experience with previous
events. You shouldn't give away that fourth mic, and the client needs
some way to compare your proposal with others he might be considering.


Again, not MY proposal. Not MY money. Not even the biggest event we do
for this particular client every year. Just my job...and I'd better
make it work...or else. Presently TTBOMK, the client is even
*considering* any other proposals; and it's a big part of my job to keep
it that way.

jak

[Mike Rivers]

Don Pearce wrote:

The big problem here is that when a radio mic causes interference to a
tv station, it isn't the station itself which notices, but the viewers.

But . . but . . . but . . . if there's a TV station on your wireless
frequency, you probably aren't going to be able to use your mic on that
frequency, so you won't operate there anyway. Interference problem
solved. Or are you considering the case where you're far enough away
from the TV station so that they don't interfere with your mic's
operation, but there's a viewer close to you and his TV set captures
your mic rather than the TV signal?

Here in the UK we have PMSE
(programme making and special events) which co-ordinates the use of
radio mics and ensures minimised interference.

Here (and world wide) we have folks like Sennheiser who can tell you
what frequencies the TV stations are using in which areas, so you can
avoid those - assuming that you have sufficiently frequency-agile
wireless systems so that you can avoid them. And if you can't,
you're still sunk because they got there first and paid for the use of
that frequency.

--
If you e-mail me and it bounces, use your secret decoder ring and reach
me he
double-m-eleven-double-zero at yahoo -- I'm really Mike Rivers
)

[Scott Dorsey]

Mike Rivers wrote:
Don Pearce wrote:

The big problem here is that when a radio mic causes interference to a
tv station, it isn't the station itself which notices, but the viewers.

But . . but . . . but . . . if there's a TV station on your wireless
frequency, you probably aren't going to be able to use your mic on that
frequency, so you won't operate there anyway. Interference problem
solved. Or are you considering the case where you're far enough away
from the TV station so that they don't interfere with your mic's
operation, but there's a viewer close to you and his TV set captures
your mic rather than the TV signal?

Actually, it doesn't always work that way. People pick a wireless channel,
and because of the FM capture phenomenon, they don't realize that there
is stuff on that channel already. And everything works fine, until the
fellow with the wireless gets a little bit too far away and the loud buzzing
appears.

Here (and world wide) we have folks like Sennheiser who can tell you
what frequencies the TV stations are using in which areas, so you can
avoid those - assuming that you have sufficiently frequency-agile
wireless systems so that you can avoid them. And if you can't,
you're still sunk because they got there first and paid for the use of
that frequency.

A lot of wireless issues appear because people don't go to those web
sites, and they don't do the intercept math to select frequencies... they
just use what worked last time and get surprised when they don't work the
next time.

And because of the FM capture issue and the fact that the transmitter is
very close to the receiver, sometimes they can get away with it in the
face of severe interference. And sometimes they can't.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Don Pearce]

 Mike Rivers wrote:
Don Pearce wrote:

The big problem here is that when a radio mic causes interference to a
tv station, it isn't the station itself which notices, but the viewers.

But . . but . . . but . . . if there's a TV station on your wireless
frequency, you probably aren't going to be able to use your mic on that
frequency, so you won't operate there anyway. Interference problem
solved. Or are you considering the case where you're far enough away
from the TV station so that they don't interfere with your mic's
operation, but there's a viewer close to you and his TV set captures
your mic rather than the TV signal?


That's true enough within the main service area of the tv transmitter,
but out on the fringes it may be a toss of a coin which affects which
first. All depends on which route has a better line of sight.

d

[jwvm]

On Sep 2, 10:29*am, Don Pearce wrote:

snip


The big problem here is that when a radio mic causes interference to a
tv station, it isn't the station itself which notices, but the viewers.
These viewers will typically be non-technical, living in marginal signal
strength areas and are probably accustomed to odd things happening to
their pictures. Notification of a problem will therefore be sporadic and
unreliable. Certainly for a one-off gig it will be over long before any
kind of investigation will be started. Here in the UK we have PMSE
(programme making and special events) which co-ordinates the use of
radio mics and ensures minimised interference.

Note that TV reception is not the issue here. This part of the
spectrum will be allocated to first responders among others.
Presumably, the Feds might get really upset if somebody died because
of interference from a wireless microphone. Of course catching the
miscreant probably wouldn't be easy.

[[email protected]]

On 2008-09-02 said:
Note that TV reception is not the issue here. This
part of the spectrum will be allocated to first responders among
others. Presumably, the Feds might get really upset if somebody
died because of interference from a wireless microphone. Of course
catching the miscreant probably wouldn't be easy.

THat was supposed to be the original plan, but when they
couldn't get anyone to "bid" on providing the infrastructure
to go with those frequencies google and other commercial
telecom providers have decided they want them. THe original
plan was indeed for first responders, but like everything
else with our FCC that's out the window in favor of big
bucks.




Richard webb,
replace anything before at with elspider

[Mike Rivers]

Don Pearce wrote:

That's true enough within the main service area of the tv transmitter,
but out on the fringes it may be a toss of a coin which affects which
first. All depends on which route has a better line of sight.

But most venues that need 56 wireless mics aren't out in the boondocks.
The local square dance caller who's been using the same wireless mic for
20 years, thinking he was being really high tech, might be upset, though.

--
If you e-mail me and it bounces, use your secret decoder ring and reach
me he
double-m-eleven-double-zero at yahoo -- I'm really Mike Rivers
)

[jakdedert]

Mike Rivers wrote:
Don Pearce wrote:

That's true enough within the main service area of the tv transmitter,
but out on the fringes it may be a toss of a coin which affects which
first. All depends on which route has a better line of sight.

But most venues that need 56 wireless mics aren't out in the boondocks.
The local square dance caller who's been using the same wireless mic for
20 years, thinking he was being really high tech, might be upset, though.

Uncasville, CT? Kind of boondockie. How about Hershey, PA? That's two
stops on the tour in question. The others are Vegas, Atlanta, Indy and
Niagara Falls.

My church uses four channels of RF on a regular basis, and we're pretty
low tech. The corporate office where I used to work regularly had eight
channels in the auditorium, one in each of four meeting rooms on that
floor, and one in each of the main conference rooms on the other eight
floors. The teleconference room on the top floor had one, and there
were two more conference rooms on that floor with one each.

I might have missed one or two...but something like 20 channels of RF
audio in the building altogether. It's right across from Vanderbilt
University--with whom we fought over spectrum--and next door (shares a
parking lot) to a conference hotel which also has several channels
(available--but in use on a sporadic basis, depending on the show booked
in).

jak