Type of internal modulation ----------------------------
fm.
Output impedance-------------------------------- --------
50 ohms.
115 volts ac 10 per-
Dial calibration accuracy --------------------------------
1.0 percent
Input power requirements-------------------------------
Weight
-------------------------------- ---------------
72 lb.
cent.
50 to 60 cycles.
125 watts.
6. Packaging Data
Output signal level-------------------------------- -------- 1
to
100,000
microvolts
When packaged for shipment, Signal Generator
(max.).
Output voltage accuracy ------------------------------- - 25 percent.
AN/URM-70 and two manuals are packed in a wooden
Modulation distortion:
crate. The crate is 221/2 inches high, 26 inches wide,
DEV MULT in X5, meter
19 inches deep, and has a volume of 6.3 cubic feet.
reading full scale-------------------------
.5 percent.
Within the wooden crate, the signal generator is
DEV MULT in X10, meter
protected from shock by a separate carton and
reading full scale-------------------------
5 percent.
Frequency stability after 2-hour
cardboard cells. Manuals are wrapped individually and
warmup -------------------------------- ----------- .03 percent per half
sealed in moistureproof bags. The total weight of the
hour.
sealed crate is 160 pounds. Cases for export shipment
Spurious fm below rated devia-
are strapped with metal bands.
tion -------------------------------- --------------- 55 db.
Deviation accuracy -------------------------------- ------ 25 percent.
Maximum spurious am-in ------------------------------
15 percent.
7. Components
Rf harmonic distortion -------------------------------- --- 3 percent.
The following chart lists the physical dimensions
Rf subharmonic distortion ------------------------------
10 percent.
of the components for this equipment.
Maximum voltage standing wave
ratio of output impedance---------------------
1.5 percent.
Number of vacuum tubes -------------------------------
17.
No.
Height
Depth
Width
Length
Volume
Unit
component
required
(in.)
(In.)
(In.)
(In.)
(cu. ft.)
weight (lb.)
Signal Generator SG-3/U-----------------------------
1
14 7/8
11 3/16
17 1/4
---------------
-------------
72
Transit Case CY-1504/URM-70 --------------------
1
18 1/32
14 15/16
20 5/8
---------------
-------------
33
Test adapter (terminated in 51-ohm shunt) ------
1
-----------
-----------
------------
------------
-----------
Test Adapter (unterminated) ------------------------
1
-----------
-----------
-----------
5 1/2
------------
-----------
Adapter Connector UG-643/U---------------------- -
1
-----------
-----------
-----------
5 1/2
------------
-----------
Adapter Connector UG-584/U-----------------------
1
-----------
-----------
-----------
----------------
------------
-----------
Adapter Connector UG-637/U ----------------------
1
-----------
-----------
-----------
----------------
------------
-----------
Radio Frequency Cable Assembly CG-718/U ---
1
-----------
-----------
-----------
48
------------
-----------
Manual -------------------------------- -------------------
2
-----------
-----------
-----------
------------
-----------
Total-------------------------------- -----------------
2
-----------
-----------
-----------
----------------
------------
105
Note. This list is for general information only. See appropriate supply publications for information pertaining to
requisition of spare parts.
8. Description of Signal Generator AN/
URM-70
All three scales of the if dial are calibrated diirectly in
a. Signal Generator AN/URM-70 consists of Signal
megacycles, and indicate the signal generator output
Generator SG-3/U shock-mounted in a transit case (fig.
frequency. The output signal strength is variable and is
adjusted by using the OUTPUT control, which is
available at the front panel (fig. 2) of the signal
calibrated directly in microvolts and decibels referred to
generator. The two frontpanel meters are an output
1 milliwatt (dbm).
level meter and an fm deviation meter. The signal
generator contains a 17-tube circuit that provides an fin
b. The power line cord, line fuses, and switch are
or continuouswave (cw) test signal within the range of
mounted on the front panel for convenience. Clips are
50 to 400 mc. The front-panel indicator lamps indicate
provided oil the panel to secure the adapter fittings and
the rf frequency ranges, green, 50-100 mc; amber, 100-
test adapters when the until is in transit or storage.
200 mc; and blue, 200-400 mc. The FREQ. RANGE-
MC selector determines the rf band used.
c. All controls and instruments on the front panel
are protected by the protruding edge of the panel. This
permits the signal generator to be
5
