How many wireless blocks do I need to work in multiple markets?

Two non-overlapping blocks, or one wideband range of 64 MHz or more, is the practical minimum for multi-market work. A single 25.5 MHz block holds only about four TV channels, so two occupied channels at a location can cost you half your coordination space.

Is a wideband transmitter worth the money over two blocks?

It usually is if the work moves cities, because wide tuning lets you relocate an entire plot in software rather than swapping hardware. The caveat is that a wide range crossing 608 MHz delivers far less legal spectrum than the label suggests, since the 600 MHz service band is prohibited nationwide.

Do the same frequencies work in Los Angeles and Atlanta?

The legal band is identical everywhere in the US, but occupancy is not — the specific TV channels in use differ by market and by address within a market. Coverage that spans separated parts of 470–608 MHz is what makes a package portable, not any particular frequency.

Should I buy blocks above 608 MHz to get more coverage?

No. The 600 MHz service band at 617–652 and 663–698 MHz is prohibited for wireless microphones nationwide, and TV channel 37 at 608–614 MHz is off limits as well. A block reaching into that spectrum adds no usable coverage in any US market.

Planning a shoot

Choosing blocks when you work in more than one market

RF ScoutUpdated July 26, 20264 min read

Buy block coverage that spans separated parts of 470–608 MHz rather than one contiguous window, because the TV channels that are occupied differ from market to market and a single 25.5 MHz block can be almost entirely blocked in a dense city. Two non-adjacent blocks, or one 64–88 MHz wideband range, lets you move an entire plot off a busy channel group instead of renting different hardware. Nothing above 608 MHz travels with you — the 600 MHz service band is prohibited nationwide, so a block that reaches into it adds no coverage anywhere.

Spectrum rules are federal. Spectrum occupancy is local. That single distinction is the whole problem with buying wireless for a career that does not stay in one city: the legal band is identical in Los Angeles and Atlanta, and the part of it you can actually use is not. Which TV channels are occupied — and therefore which slice of your block is off the table — changes with the market and, within a market, with the address.

Why a single block is a trap

A 25.5 MHz block holds roughly four 6 MHz TV channels. If two of them are occupied at your location, you have lost half your spectrum before the first battery goes in. In a light market that rarely bites. In a dense one it can leave a nominally eight-channel package coordinating four, and no amount of careful intermodulation planning invents room that is not there.

The trap is that the failure is invisible at purchase. One block looks like a complete system in the shop and on the first ten jobs, and then becomes a rental line item the first time the work moves cities. The fix is not more transmitters — it is spectrum in a second neighbourhood of the band.

What each coverage strategy actually buys

Block coverage strategies compared
Strategy	Usable spectrum carried	How it travels
One 25.5 MHz block	About 25 MHz in one place	Fine in a light market, brittle in a dense one
Two adjacent blocks	Less than 51 MHz once overlap is counted	Better depth, still one neighbourhood of the band
Two separated blocks	About 51 MHz in two places	Survives one busy channel group outright
One 64 MHz wideband range	64 MHz continuous	Slides a whole plot off an occupied group
One 88 MHz wideband range	88 MHz continuous	The most freedom available below `608 MHz`
Anything reaching above `608 MHz`	Less than the label claims	Adds nothing in any US market

The case for wideband tuning

A 64 or 88 MHz range is the same argument as two separated blocks, without the hardware split. The practical difference shows up at the moment a location turns out worse than expected: with wide tuning you move the plot, re-run the coordination and keep working. With a single block you start deciding which characters lose their radio mic.

Wide tuning is only as wide as the legal band. A range printed as 572–636 MHz gives you 36 MHz in the US, not 64.
Transmitters and receivers must both cover it. A wideband receiver paired with narrow transmitters travels no better than the transmitters do.
IEMs count. In-ear packs occupy the same spectrum as the mics and belong in the same plan, not as an afterthought.
WMAS is a different lever on the same problem. It changes how much audio fits inside a given megahertz rather than giving you more megahertz — see WMAS explained.

A shape that survives four cities

Anchor everything below `608 MHz`. That is 138 MHz of legal band and the only spectrum that behaves the same in every US market.
Separate your two windows. One package low in the band and one higher up fails independently; two neighbours fail together.
Keep a non-TV-band fallback for a channel or two. 902–928 MHz, 1920–1930 MHz and 2400–2483.5 MHz are legal nationwide without a license — see working above 700 MHz.
Do not count the slivers as coverage. 614–616 MHz and 657–663 MHz are legal unlicensed at 20 mW EIRP, and 653–657 MHz is licensed only. They are a bonus, not a plan.
Decide about licensing separately. A Part 74 license buys power and the 653–657 MHz half of the duplex gap, not more markets — see do you need an FCC license.

Check the market, then check the address

Market-level knowledge tells you what kind of problem to expect; the address tells you what you will actually face. A location twenty miles from a transmitter site and one in its shadow can share a ZIP code prefix and behave nothing alike. Start with the market page, then run the specific address before the truck rolls.

Los Angeles — dense market, heavy production traffic on top of broadcast occupancy.
New York — dense market, and neighbouring productions matter as much as broadcasters.
Chicago — a full major-market channel load in a compact footprint.
Atlanta — high production volume, spread over a wide metro area.

Whatever the scan shows on arrival, a scan only reports the moment you took it. Combining a location read with a proper walk test is how the plan survives contact with the day — and if it does not, troubleshooting dropouts and hits is the next stop.

Run the same block list against several addresses and see which coverage gaps follow you around.

Compare your blocks across markets

Common questions

How many wireless blocks do I need to work in multiple markets?: Two non-overlapping blocks, or one wideband range of 64 MHz or more, is the practical minimum for multi-market work. A single 25.5 MHz block holds only about four TV channels, so two occupied channels at a location can cost you half your coordination space.
Is a wideband transmitter worth the money over two blocks?: It usually is if the work moves cities, because wide tuning lets you relocate an entire plot in software rather than swapping hardware. The caveat is that a wide range crossing 608 MHz delivers far less legal spectrum than the label suggests, since the 600 MHz service band is prohibited nationwide.
Do the same frequencies work in Los Angeles and Atlanta?: The legal band is identical everywhere in the US, but occupancy is not — the specific TV channels in use differ by market and by address within a market. Coverage that spans separated parts of 470–608 MHz is what makes a package portable, not any particular frequency.
Should I buy blocks above 608 MHz to get more coverage?: No. The 600 MHz service band at 617–652 and 663–698 MHz is prohibited for wireless microphones nationwide, and TV channel 37 at 608–614 MHz is off limits as well. A block reaching into that spectrum adds no usable coverage in any US market.

Sources

Related notes

Field Notes are general reference, not legal advice or a substitute for the rule text. Spectrum rules change; verify anything you are relying on against the current source before you transmit. See the methodology and disclaimer.