I
NOTES
SERVICE
I HEWLETT-PACKARD COMPANY 275 PAGE MILL ROAD PAL0 ALTO, CALIFORNIA, U. S. A.
I
CABLE "HEWPACK" TELEPHONE DAVENPORT 5-4451
I
DRIVE CABLE REPLACEMENT IN HEWLETT-PACKARD INSTRUMENTS: M14
I
AUDIOOSCILLATORS ...... . .MODELS 200H, 2001, 200T, AND 201B
AUDIOSIGNALGENERATOR ... .......... MODEL 206A
i I DISTORTION ANALYZER ..... ... MODELS 330B, 330C, AND 330D
TEST OSCILLATOR ....... .......... MODEL 650A
I
I
1
Two drive cables, one 11 in. and the other 15 in. (length
before end loops are formed) will be required to re- n
place the drive cables in the above instruments. These
two drive cables are available from Hewlett-Packard.
CABLE REPLACEMENT PROCEDURE. (Refer to
Figure M14-1.)
I
1. Remove old dial cable and screws at A, E3, _C, and
D. Loosen SET SCREW in SPRING LOADING COL-
EAR on rear of DRIVE SHAFT.
I
2. Insert free end of 11 in. cable through hole 4 of
DRIVE PULLEY and form loop in end of cable as
I directed in Figure M14-2.
1
3. Set instrument tuning dial to high frequency limit
I
and rotate tuning capacitors so plates are open full.
I Fasten cable at Aand thread as shown in Figure M14-1
SET SCREW
with other end fastened by screw at on LARGE
DRUM.
4. Repeat steps 2 and 3 using the 15 in. cable. Start
at _C and finish at D on the SMALL DRUM.
I
5. Revolve SPRING LOADING COLLAR counterclock-
wise (viewed as shown in Figure M14-1) until slack
is removed from drive cables. Rotate an additional Figure M14-1. Exploded Rear View of Drive Cabling
half turn counterclockwise to tighten SPRING and
tighten SET SCREW. INSTALLATION OF CLAMPING EYELETS ON ENDS
,
OF NEW PLASTIC COATED CABLE
6. Position cable on LARGE DRUM so that first turn
from DRIVE PULLEY goes around LARGE DRUM in A new type plastic coated braided wire with a stain-
a plane perpendicular to the axis of the drum and less steel core is now supplied for replacement pur-
tangent to the outside of the DRIVE PULLEY. Cable poses.
between IDLER PULLEY and SMALL DRUM should be
positioned so that it does not rub in notch in the ver- This new cable is more durable and not so apt to be-
tical center post. come frayed and broken. A different fastening technique
must be used for the end loops since the heat of a
7. Rotate tuning dial from one stop to the other for soldering iron would damage the plastic coating. The
approximately 100 complete cycles to work out any plastic coating slides on itself and a knot will not hold
stretch and allow cables to position themselves on the a loop tied in the end of the cable.
drums. Rotors of tuning capacitor sections should not
be at the limit of their travel at either end of tuning Special clamps in the form of small eyelets are sup-
range. plied with the replacement cables for the instruments
listed.
8. Check dial calibration. If a constant error appears,
The replacement cables are supplied from the factory
loosen set screw in DRNE PULLEY and rotate pulley
with a loop formed in one end. The other end is not
slightly as required to correct this error. If complete
looped since it is necessary to thread this end through
recalibration is required, refer to the Instruction
a hole in the pulley before the loop is formed. (See A
Manual or contact the factory for instructions.
1 of Figure M14-2.)
I
Complete Coverage in Electronic Xeasuring Instruments |