Cost of installing HD?

Garrett Wollman
Sat Jun 3 23:43:17 EDT 2006

<<On Sat, 3 Jun 2006 13:21:10 -0400, "Don A." <> said:

> REcently, Dan mentioned that the cost of adding HD is an investment of
> "Hundreds of $K's"...

> It seems that HD would be a pretty simple install, no?  Simply injecting the
> data streams into the signal.  (That and the costs of licensing.)

> Can anyone verify what the cost is to a small to medium station to add HD
> capabilities?

It's very expensive.  The minimum cost seems to be in the range of
about $65,000, for a non-directional AM which already has an HD-ready
transmitter.  Consider what's required:

For all stations:
- An HD-compatible processor
- An iBiquity-licensed exciter
- An iNiquity-licensed "exporter" to encode the main program audio
- An iBiquity-licensed "importer" for any NPAD and multicast audio
- An HD-compatible transmitter (or integrated exciter/transmitter)
- Monitoring infrastructure for the HD signal

For AM stations:
- A sufficiently-broadband antenna system to pass the HD sidebands
(particularly for critical directional arrays)
- A remote control to turn the HD off at sunset and back on at 6 AM

For FM stations:
- A new HD transmitter, combiner, and reject load, or
- A linear power amplifier, or
- A new HD or dual-input antenna

The FMs are turning out to require substantially more investment than
the AMs are, in a lot of cases, because of the requirement for linear
amplification of the HD signal.  Most high-power FM transmitters, like
the Continental 816, operate non-linearly, because that mode is much
more power-efficient.  If for some reason a station is not able to
install a new antenna (either HD-only or dual-input), perhaps because
it's a shared antenna, or because of tower loading issues, or just a
lack of space, then they are stuck with one of the combining options.
High-level combining involves a separate transmitter just for HD
(usually with a bit of the analogue signal as well); the two are
combined, and about 10% of the power to the combiner is dumped in a
reject load.  In low-level combining, the exciter generates a combined
FM and IBOC signal, which must then be linearly amplified at the
transmitter; for high-power installations, this comes at a cost of
about 30% (from 85% down to 55%) in conversion efficiency.  Either
way, more power and often more space are required in the transmitter


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