Section Ill. OPERATION UNDER USUAL CONDITIONS

Figure 16. Controls, facsimile transceiver TT-1F/TXC-1.

supplied with Facsimile Set AN/TXC-1D. This

be diverted to ground. It is therefore not neces-

switch is located on the blower and canister sup-

sary for the operator to be with the equipment

porting bracket (fig. 2) and should be thrown to

at the end of a transmission.

the ON position only when the equipment is used

d. Blower Switch (S9). A toggle ON-OFF

for direct recording.

switch is provided for the dust removal blower

Section Ill. OPERATION UNDER USUAL CONDITIONS

Note. The operating instructions in this section are based on the use of a voice communication circuit between

transmitting and receiving operators. Blind circuits, however, in which transmission and reception of facsimile copy are

completed on prearranged schedules, are feasible without voice communication. Experienced operators will find numerous

satisfactory ways of saving time by varying the operating procedures described in this section.

Satisfactory operation may be obtained even

23. Preparations

though the indexes of cooperation are not exactly

Before operating Facsimile Set AN/TXC-1(*),

determine the type of circuit being used, wire or

the same. Differences of as much as 5 or 10 per-

radio, and all types of transmission and reception

cent are generally not noticeable in photographic

desired; this will affect the operating procedure.

or message copy. The indexes of cooperation

a. Index of Cooperation. Transmitting and

may differ by as much as 50 percent for weather

receiving equipments at each end of the circuit

map work or other line illustrations without

should have the same index of cooperation, the

affecting the usability of the received copy. The

same speed, and a recording system responsive to

maximum speed tolerance between the trans-

the modulated signal of the transmitter. The

mitting and receiving scanning drums of Facsimile

index of cooperation is equal to the scanning drum

Transceivers TT-1(*)/TXC-1 is .00033 percent.

diameter times the pitch (lines per inch scanned);

The table below lists the standards applicable in

thus, the index of cooperation of Facsimile

present day military and commercial wire and

Transceiver TT-1(*)/TXC-1 is equal to 6 (drum

diameter in inches) 96 (lines per inch) = 576.

radiophoto facsimile circuits.