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Strategic Comm Systems

     In the wake of World War III, landlines would be cut, microwave links destroyed by EMP, and many satellites shot down or left to spiral down into the atmosphere. The Project wasn't nearly about to launch its own set of communications satellites covertly (one way to inadvertently cause World War III, at least!). There was some uncertainty about the effectiveness of long-distance radio transmission in the wake of a nuclear war, but in the end the Project decided to stick with radio transmission.

     Team activation signals, and low-rate strategic messaging, are sent on VLF frequencies -- 14 to 40 kHz for the Project. Transmitting antennae for this system are very large -- a few kilometers across for a trans-continental system -- and transmission is very inefficient; power requirements are high. However, receiving antenna are simple coils, as small as 10 cm in diameter; and the receiving radios in boltholes are an unimpressive piece of rack-mounted equipment (including decryption equipment).

     The actual coil antenna used for Project boltholes is about 30 centimeters in diameter, wound with more than a thousand loops of insulated wire (so: more than a kilometer of wire). Note that the antenna design doesn't tell you much about the frequencies being received, except that it's VLF. It's placed just at the surface for most boltholes, mounted on a sturdy pillar anchored in the bolthole structure. An artificial rock of thick, fiber-reinforced polyimide resin is also mounted on the pillar, and encases the antenna; it's very strong, chemically resistant, and fireproof up to at least 800° F (1300° F for brief periods). The artificial rock also means the team probably won't be able to get at the antenna wire. The rock will probably look a kind of weird, weathered yellow-orange color after 150 years out in the open.

     The transmission rate, using FSK modulation, is about 5 characters per second (using ASCII 8-bit characters). Encryption padding and other "non-text" parts of  messages roughly double the transmitted wakeup signal. A wakeup signal might be 300 characters of useful information -- 600 characters as transmitted in encrypted format:  thus 2 minutes to transmit. Besides the actual reactivation signal for the automated systems in the bolthole, the message can contain immediate-action instructions for the team -- presumably "conditions are thus", "go here" and "monitor these radio frequencies" sort of stuff.

     The Project thought there would still be some functioning satellite communication systems until at least 1995.

Tactical Comm Systems

     Most teams employ the PRC-70 radio for long range radio communication. When set up as a backpack radio, the range between two PRC-70 sets is about 25 kilometers (with the 2 meter long "fishing pole" antenna); when installed as a vehicle radio, range is about 800 kilometers between two sets. 

     The AS-2975 is a center-feed horizontal dipole antenna; it increases reception by 50% over a plain "isotropic" antenna (like the usual vertical whip), but only in two directions at right angles to the antenna. The lobes are about 60 degrees wide each. As a ballpark, it will add 50% to the range for voice communications between sets along the two lobes, and allows reception of Morce code up to 4000 kilometers distance.

     The AS-2259 is a near-vertical incidence skywave antenna, erected on a 5 meter tall mast. It can extend voice communications to about 1000 kilometers (although there will be "nulls" with no coverage).

Project Encryption

     An example of Project encryption. This message was sent on 24 August 2140, about 6 pm PT/7 pm MT/8 pm CT/9 pm ET:

BEWARE CANADA TRAP AT BILLINGS THEY ARE NOT MORROW HAVE TRAPPED AT LEAST ONE MP TEAM PREVIOUS ANY TX FROM CANADA OR VIC LIKELY BAIT THEY ALSO HAVE RDF AND AIRCRAFT KEEP TX SHORT THEY MONITOR SHORTWAVE NOT MANY USERS IN US GOOD LUCK OUT

     It encrypts as:

ALYG ENAX VTFS NMMB DIUC OBVQ LFGA XNTJ RQBK RFFL JZAI ETAT EFWH WQCU CVXR FQPV MEYS DHYO BFRV AOXE OLUS NQAY OXBF ZISC BTHM DXHJ FWDI SWGK WEER BRSN FJIW JRYW WGJQ XSRJ YIZK UHUV QFRD YVPT VKVC LBTN GVDZ OXPJ VFNN JOQZ ZJNX VXPV TDEZ XCY

     ... and displays as:

BEWA RECA NADA TRAP ATBI LLIN GSTH EYAR ENOT MORR OWHA VETR APPE DATL EAST ONEM PTEA MPRE VIOU SANY TXFR OMCA NADA ORVI CLIK ELYB AITT HEYA LSOH AVER DFAN DAIR CRAF TKEE PTXS HORT THEY MONI TORS HORT WAVE NOTM ANYU SERS INUS GOOD LUCK OUT

As displayed on a Morrow Project PC.

Radio Pro Words and Phonetic Alphabet

Visual Signalling