Chapter 4 — TEMPERATURE, HUMIDITY, AND PRECIPITATION 



Recorder and Case Assembly 



The recorder and case assembly is a con- 

 venient means of combining in a single as- 

 sembly the receivers, recorders, and power 

 controls for the three systems. A synchro- 

 nous motor drives the chart. One ink reservoir 

 supplies the air temperature and dew-point re- 

 cording pens. The rainfall recording pen has 

 an independent ink reservoir. The power input 

 for all three systems as well as for the re- 

 corder is in the recorder case assembly and 

 is designed for 11 5- volt, 60-cycle, ac. The 

 power switch for the three systems, the re- 

 corder lights switch, and the chart drive speed 

 switch are also in the recorder case. 



Operation 



As its name indicates, the semiautomatic 

 meteorological station requires a minimum of 

 operating procedures. The main switch, gov- 

 erning the recorder and the three systems, 

 is at the front of the recorder case at the left 

 side. Placing it ON provides current for the 

 recorder, the transmitters, the rain gage, and 

 the dewcei power supply. The transmitters op- 

 erate automatically as soon as current is sup- 

 plied to them. The only operation required for 

 the rain gage is emptying the measuring 

 cylinder. 



FILLING INK RESERVOIRS AND PENS.— 

 Ensure that the main power switch is turned 

 OFF. Lift the pens from the chart by using 

 the pen lifter; then remove the pens by lifting 

 them straight up and out of their carriage 

 slots. Lift the reservoirs out of the recesses 

 in which they are located. Be careful not to 

 spill any of the remaining ink on the recorder, 

 as removal of the ink is difficult. Fill the 

 reservoirs about three-fourths full of ink. Care- 

 fully replace the reservoirs in the recorder. 

 Place the pens in the slots in their respective 

 carriages. Using a common soda straw, fold 

 the end over and pierce a small hole with 

 a pin about one-fourth inch from the folded 

 end. Insert the pen tip in this hole and suck 

 on the open end of the straw until ink is drawn 

 through the pen tube into the straw. The trans- 

 lucent material of the straw allows the op- 

 erator to see when ink is entering from the 

 pen. Remove the straw. 



Maintenance 



Inspect all wiring periodically to ensure 

 that electrical lines are intact. Set up inspection 

 periods commensurate with existing climatic 

 conditions. Visually inspect all housings or 

 casings for corrosion or deterioration. Refer 

 all other maintenance problems to your super- 

 visor. Maintenance beyond operator maintenance 

 is not the responsibility of the Aerographer's 

 Mate. 



RECORDER. — Replace the light bulb as re- 

 quired. Visually inspect pens to see that they 

 are not bent or distorted. If distortion can 

 be corrected by straightening the pen manually, 

 bend it into shape. If the distortion cannot be 

 corrected by straightening the pen manually, 

 remove and replace the pen. Never allow the 

 pens to dry out with ink in the bore. Clean 

 the pens and reservoirs periodically, deter- 

 mining the periods on the basis of existing cli- 

 matic conditions. A piece of music wire is 

 furnished for cleaning the bore of the pen tips 

 if they become clogged. 



CLEANING THE PENS AND RESERVOIRS.— 

 Chart lint should be wiped from the pen tips 

 if a fuzzy or broad line indicates that lint is 

 present. If the system is to be shut down or 

 unused for extended periods of time, empty 

 the reservoirs and wash them with clear water. 

 Ink can be cleaned out of the pens by holding 

 them so that a moderately strong faucet stream 

 is directed to the reservoir end of the pen 

 tube. If the force of the water is insufficient 

 to flush out the pens, use an ordinary ear sy- 

 ringe filled with water inserted at the reservoir 

 end of the pen tube. Blow the water out of the 

 pens after they are flushed. 



PERIODIC INSPECTION OF RECORDER.— 

 Inspect the record chart daily for a clear 

 legible record trace, proper time setting, suf- 

 ficient chart reserve, takeup without binding, 

 and agreement of recorded values with the 

 indicator readings. 



Inspect the pens daily for evidence of clogged 

 ink, fuzzy line on the record, and recording on 

 sudden swings. 



Inspect the ink tanks weekly to see that 

 sufficient ink is in the tanks. 



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