Chapter 7 — COMMUNICATIONS EQUIPMENT AND OPERATIONAL PROCEDURES 



Changing Tape 



Some models of teletypewriters have the 

 capability of preparing perforated tapes which 

 can store the characters for automatic trans- 

 mission. Procedures for changing the perforated 

 tape are contained in the operator's instructions 

 of those machines. 



FACSIMILE 



Many weather offices are equipped with fac- 

 simile equipment used to receive and record 

 maps, photographs, or messages. Facsimile 

 equipment is being replaced by Naval Environ- 

 mental Display Station (NEDS) which is covered 

 in Chapter 9, of this manual. In addition, certain 

 selected stations such as Fleet Weather Cen- 

 trals, are equipped with special units called 

 transceivers, which transmit as well as record 

 the facsimile messages. Facsimile transmission 

 may be accomplished either by wire (landline) 

 or by radio. In the United States the method 

 of transmission is principally by wire. Stations 

 aboard ship or overseas receive facsimile 

 weather charts by radio on certain designated 

 frequencies of Navy broadcasts or by inter- 

 cepting other transmitted frequencies contained 

 in the Worldwide Marine Weather Broadcasts 

 manual. 



ALDEN FACSIMILE 



The Alden Weather Map Receivers are fully 

 automatic, continuous weather map receivers 

 which use the simple electromechanical principle 

 of the Alden recording technique and Alfax 

 electrosensitive paper on which electricity is 

 the ink. The two types in general use today are 

 the Alden Standard All Purpose 19 Recorder 

 (fig. 7-5), and the Alden 18 Auto Select Fac- 

 simile Recorder, which is available in the con- 

 sole model and the bench model (fig. 7-6). 

 The paper used in the recorder is white and 

 comes in 170-foot rolls. A crisp sepia map on 

 a clean white background is produced. The 

 paper is thin and suitable for reproduction di- 

 rectly by the Bruning or Diazzo (Ozalid) pro- 

 cess. It is packaged in a sealed plastic bag 

 and can be stored indefinitely without dating. 



1. Master ac power 



7. Manual fast paper 



switch. 



advance. 



2. Automatic fast feed 



8. Marking signal 



3. "No paper" indi- 



test switch. 



cator. 



9. Signal monitor 



4. Program clock. 



switch. 



5. Signal level. 



10. Manual start switch. 



6. White level. 







209.342 



Figure 7-5. — Alden 



Model 19 Facsimile Re- 



corder. 



With the front cover open, the roll of paper 

 is easily snapped into place. After closing, the 

 cover seals the paper in the recorder, pre- 

 venting moisture loss. 



A special feature of the receiver is an easily 

 changed programming clock for automatic chart 

 selection and recording. A change in scan rate 



127 



