DC POWER SUPPLY TESTS

TM 11-5820-918-13

Repeat the above procedure for frequencies between 15-16 and 29-30 MHz.

h. If readings in steps f and g between the 1024 frequency display and frequency

counter do not agree, replace the 1024 transmit logic (1A2) or sweep synthesizer (1A1)

module.

Turn off TCS-4B transmitter and replace cable removed in step a.

5-24. DC POWER SUPPLY TESTS. The following test is subdivided into checks on

the three individual units comprising the transmitter. All voltages are labeled ad-

jacent to the test points. Note that some DC voltages are proportional to the incoming

line voltage. If the average line voltage differs substantially from 115 (or 230) VAC,

refer to adjustment procedure for AC input compensation. If no adjustment is provided

for an out-of-spec voltage, the unit is probably defective and should be returned

to the depot for evaluation and repair.

5-25. 1024 (UNIT 1) POWER SUPPLY TEST.

a. Remove top cover, and release captive screws on both modules A1 and A2.

Stack up modules for access to test points.

b. Use a multimeter to check the following voltages (figures 5-5 and 5-6).

(1) At test points +5V (A) and (B) measure 5 0.25 VDC

(2) At test point +5V (C) measures 5 0.75 VDC

(3) At test point -12V measure -12 0.75 VDC

(4) At test point +12V measure +12 0.75 VDC

(5) At test point +24V measure +24V 1.50 VDC

c. AC line ripple should be less than 10 mV peak-to-peak on regulated supplies

and less than 1 volt peak-to-peak on the +5C supply.

5-26. STANDBY BATTERY SUPPLY TEST. Two different types of standby battery

assemblies are used in the TCS-4B. Some transmitters have a non-rechargeable bat-

tery assembly (part number 6025-1008) that uses standard D-cell batteries. Other

transmitters have a rechargeable battery assembly (part number 6025-1018) that in-

cludes an integral charging circuit and uses sealed lead acid cells. Conditions for

testing the charge of the battery supply differ between the non-rechargeable and

rechargeable assemblies. These different conditions are noted in steps a and b below.

The test results as defined in step c apply to the test of non-rechargeable and re-

chargeable assemblies.

a. For the non-rechargeable battery assembly (P/N 6025-1008), a test may

be con-

ducted at any time during operation with AC line power on or off and the BAT

switch

on. Pressing the TEST pushbutton switch on the 1024 front panel initiates the

test

and the BAT lamps light to indicate the charge condition of the battery supply

as de-

scribed in step c below.