B1-8 INSPECTING AND TESTING THE RADIOSONDE 
recheck it after about one week. If at the end of this time the 
contact point is within one contact of the proper setting, ac- 
cept the radiosonde or modulator; otherwise, reject it. The 
correct method of contact setting is explained in JB2-15.5. 
d. With the contact point set in accordance with (c) above, turn 
the detent knob clockwise and counter- clockwise about one rev- 
olution and determine that there is relative motion between the 
contact point and commutator. 
e. With the contact arm lifting lever in its lower position, check 
visually (by sighting along the lifting bar) to make sure that 
the pen arm will not touch the pen arm's lifting bar at any 
point along the commutator (do not move the arm manually). 
Invert the instrument and check thatthe contact point remains 
in contact with the commutator arm. Liftthe contact arm after 
this inspection is completed. If the baroswitch fails to meet 
the above requirements, reject the radiosonde, 
1.5 Relay. The radiosonde relay, mountedon the transmitter chasis or 
near the baroswitch, is protected from foreign particles by a plastic 
cover. The relay will not be cleaned, adjusted, or uncovered for any 
reason. If the radiosonde is received with the plastic cover off the relay, 
replace the cover carefully, and if the radiosonde passes all other 
checks, accept it for use. Radiosondes with relay defects will be re- 
jected (see §B1-2.11). 
1.6 Separate Transmitter Unit. Check for cracks or breaks in the 
case. If any damage is observed that would interfere with normal oper- 
ation, reject the unit as defective. Reject transmitters that have broken 
plugs or cable leads, and those that cannot be securely attached to the 
radiosonde. 
LC Radiosondes with Hypsometer Units. If the bead thermistor is 
visible or if there are broken leads or other visible damage, reject the 
radiosoned. 
1.8 (WB) Inspection Stamp. Radiosondes received from the manufac- 
turer must have a government inspection stamp; ifno stamp is found, re- 
ject the radiosonde. The stamp may usually be located on the battery 
compartment door, in the transmitter holder or near the battery clamps. 
Reconditioned radiosondes need not have a government inspection stamp. 
oN Testing the Radiosonde. If possible, the tests will be made upon 
receipt of the radiosonde; otherwise, they will be made at the time the 
radiosonde is being checked for the flight. 
Ik (6g) FMH#3 
