Full front view of 3 bay trnsmitter
Shown on skid in Dallas warehouse awaiting transport -
High Seas # 5 - Click on image for larger view.
Rack of electronics
More Electronics in left rack

Rack of electronics
Bottom part of electronics rack

Inside PA cabinet, power control switching. Front Left Electronics
 Rack-High Seas # 5 - The difference in coloring of the transmitter
and the other pictures is due to a different camera being used to
take this picture and, of course, much different lighting conditions.
The true color of the transmitter is more like the other pictures.
Harris name plate/serial number tag


Shown with 4CX15000A tube installed
PA metering panel in PA section 

IMRADIOHA WebMaster Note: The content on this page was originally at:
Harris740M.htm and was a sales pitch for the unit which was sold for $2900. After the sale the page was removed. It was recovered from the Internet Archive and modified to remove the sales promotion content and show just the transmitter information.

This is the last of 17  Harris 10 KILOWATT Transmitters from the AT&T Pennsuco Fl. Station {WOM} Transmission Site.  These transmitters were in operating condition when  the site was closed. 

AT&T had 3 sites that had these popular Harris 10KW HF transmitters, Ocean Gate, NJ {call sign: WOO} Dixon,  CA {KMI} and the Pennsuco, Fl site {WOM}. This transmitter came from the Pennsuco site and was one of the later versions.

The Ocean Gate site has been preserved by the local Township, the Dixon site is no longer, and now the Pennsuco site has been dismantled and sold to land developers.

This link will take you to the Ocean Gate, NJ website and you can prowl around this very nice and well done site created by Albert LaFrance . see:   and scroll down till you come to "Interior - second floor - east (addition) equipment room"  The pictures there pretty much show these Harris 10 KW sets as they were installed much like at the Pennsuco site, the big difference being the Pennsuco site [late 1970's] WOM was built much later than the Ocean Gate site .

This transmitter uses the very popular Eimac 4CX15000A tube for the final PA stage.  The 740-M set is full AUTO TUNE and in fact easier to tune in the auto tune mode than manually, and a whole lot quicker.

These sets normally require 3 phase electrical power for operation, any voltage and combination of 50/60hz is all selectable by the interior auto transformers.

This transmitter will operate on AME, USB. LSB, ISB, and CW/DATA modes.  4 channels of information can be transmitted in the ISB mode. The IPA is very simular to the more common Harris RF-110A  1 kw amp that uses a pair of the 4CX1500B tubes.

The set offers a 3 setting power output selection control setting of 1.25kw, 4kw or the full tilt 10kw power position. The transmitter operates on any frequency between 2 and 30MHz in any of the modes stated.

As they were set up, the transmitter is attached to a 1 piece skid/base combination, using 3 cabinets. The set weighs about 2400 pounds and measures right at 40" deep 78" high  and 72" wide.

These transmitters had every kind of fail-safe scheme known to man to safeguard the operators as well as to protect the equipment from problems along with special wiring required by the ship-to-shore AT&T usage required by their mission.  As usual, RF Harris built extremely professional broadcast equipment and this transmitter is no exception.

PA metering panel in PA section

 Some of inside of PA section with protective covers off

Just more electronics in left rack cabinet