operati g and aint nance manual

33 Pages·2007·9.26 MB·English

SOLID STATE
VARIABLE FILTE R

MODEL 3550 SERIAL NO.__
OPERATI G AND AINT NANCE

MANUAL

KRD - ITE CDR PCRATID
Avon Industrial Park/Bodwell St., Avon, Massachusetts 02322
CD
1975 KROHN- HITE CORPORATION

Con tents
CO NTENTS
Se ction P age
1 GENERAL DESCRIPTION . . . . . . . . . I
2 OP ERATING I STRUCTIONS . . • . . .. 4
3 INCOMING AC CEPTANCE AND INSPECTION I I
4 CIRCUIT DESCRIPTION . . . • . 15
5 MAINTENANCE ....•.. 20
6 CAL IBRATION AND ADJUSTMENT 24
ILLUSTRATIONS
F igure P age
1-1 Model 3550 Multifunction F ilter .
ii
2-1 Front and Rear Pane ls .
5
2-2 Pass Band Characteristics .
8
2- 3 Normalized Attenuation Chara teristics
8
2-4 Squa re Wave Response ..' . ....
8
2-5 Phase Shift . . . .
e • • • 9
4 -] lock Diagram . . • • . . . . .'

16
4-2 Response of Quadratic Amplifiers •

17
5-1 Trims and Adjustments . ..

21
Appendix

Schema ti • Layout and Parts List ~
E nd
TABLES
Table
Pag e
3- ] Acceptance Checkout P r ocedur
12
5- ] Test Point vs Signal Voltage
22
6- 1 Calibr ation P rocedure . . . .
26
F ilter, 3 550

.1 . 10 ,100
.IK
INPUT I<ROH -HITE
mode. 3550 filter
F ig u r e 1-1, Model 3550 Multifunction Filter
ii
Section I - General Description
SECTION 1
GENERAL DESCRIPTION
1.1 INTRODUCTION
The Krohn -Hite Model 3550, shown in Figure 1-1, is a multifunction filter
that operates in a high-pass, low-pass, band-pass, or band-reject mode.
The cutoff frequencies are independently adjustable between 2 Hz and 200kHz.
An optional rack-mounting kit (Part No. RK-38) is available fr om Krohn -Hite
(or installing the Model 3550 in a standard 19" rack spacing.
1.2 ELECTRICAL SPECIFICATIONS
Function
Low -pass , high -pass, band-pass, band-reject.
Cutoff Frequenc y Range
BAND MULTIPLIER FREQUENCY (Hz)
I O. 1 2 -20
2 I 20 -200
3 10 20 0 -2000
4 l Oa 2, 000 -20, 000
5 lK 20 , 000 -200, 000
\
Frequency Can1 ,01
Low-pass and high-pass functions each have one decade dial and a 5-position multi­
plier switch, effectively a 30 inch long scale for the 5 frequen cy bands.
Cutoff Frequency Cal ibrc tion Accu 'a cy
±50/0 bands 1 thru 4, ±lO% band 5 with RESPONSE switch in MAX F LAT (Butterworth)
position; less accurate in LOW 0 position. Relative to m id-band level, the filter
output is down 3dB at cutoff in MAX F LAT position and approximately .12.dB in
LOW 0 posi tion.
Bandwidth
°
Low-Pass Mode: From approximately 0.2 Hz to cutoff setting between 2. Hz to
200 kHz ,
Filter, 3550
High-Pass Mode: From cutoff se tting of 2. 0 Hz to 200 kHz, to approximately
3 MHz.
Band-Pass: Both cutoffs adjustable from 2. 0 Hz to 200 kHz , For m inim um band ­
width (Butterworth response) both cutoff frequencies are set to coincide. This
pr oduces an insertion loss of 6 dB, with the 3dB po ints at 0 .8 and] . 25 times the
mid-band frequency.
Band-Reject: Both cutoff frequencies adjustable from 2. 0 Hz to 200 kHz. Lower
pass band to approximately 0. 2 Hz, upper passband to appro ximately 3 MHz. A
sharp null can be obtained by setting the High Pass section to about twice the null
frequency, and the Low Pass se ction to half the null frequen cy, and alternately ad­
justing both dials for minimum response.
Response Charocteristi cs
Choice of 4 pole Butterworth (Maximally fiat response) for frequency domain opera­
tion and L ow Q (dam ped response) for transient-free tim e dom ain operation,
selected by mean!') of a switch on the rear panel.
Attenuation Slope
Nominal 24 dB per octave In all rnodes of opera tion.
Pa$S Band Gain
Zero db + 1 db in pass band.
Maxi mum Attenuatian
Greater than 60 dB

Input Character; stic 5

Max Voltag e : ±7V peak to 2 MHz.

Max DC Component: ±lOOV.

Input Irnpedance : 10 Megohms in parallel with 50 pi.

Output Characteri 51iC5

Max Voltage : ±7V peak to 2 MHz.

Max Current: ± 15 rna peak.

Internal Impedance: 50 ohms.

Hum lind Hoi se

Less than 200 uv, except 400 uv in "BAND REJECT" rn od e ,
2
Section 1 - General Description
Output DC Leve l Stobi Iity

±l my/ oCt ±l rnvZhr. Somewhat gr eater in BR m ode.

Front Panel Control s
High Pass Section: Hz dial and multiplier switc h.

Low Pass Section: Hz dial and multiplier switch .

Function Switch: LP, HP, BP, E R.

P owe r ON Switch

Reor Ponel Control s
Resp onse Switch: MAX FLAT, LOW Q.
Ground Switch: CHASSIS, FLOATING.
DC Level: Potentiomet er.
L ine Switch: 115V/230V.
Terminals
F ront and re ar panels, one ENC connector for INP UT, one for OUTPUT. AC power
recepta cle with det achable line cord. One rear terminal for chassis grounding.
POWIIT Henuirernants
105-125 or 210-250 volts, single phase, 50-400 Hz, 10 watts.
Operating Temperature Range
occ to 50aC.
Dimensions and Weights
Overa ll D im e n s ion s We i ht
Model Widt h Height Depth Net Shipping
3550 8 1/ 2" 3 1/ 2" 13 " 9 Ib/4kg 14 Ib / 7kg
3
Filter, 3550
SECTION 2

OPERATING INSI CIIONS

2.1 INITIAL SETUP
The filter is adjusted and checked car efully in our test department to insure that it
meets all specifications. It is then aged and tested again before shipment. The
filter is shipped complete and afte r unpacking is ready for use.
The Model 3550 should be unpacked carefully and ins pected for damage that may
have oc c u rred in s hipping. Check all controls for freedom of operation.
The Filter may be oper ated from an AC power source of either 10 5- 125 volts,
50-400 Hz, or 210 -250 volts, 50-400 Hz. A I1 5/230V LINE witch, located on the
rear panel, selects the filter's mode of operation, When the AC line is 115V, m o ve
the LINE switch to the I 15V po sition. In t his mode, a 1/8 amper e 510-blo fuse ITlUSt
be used. When the filter is to be opera ted from 230 VAC, move the LINE switch to
the 230V po sitio n, and re place the fuse with a 1/ 16 amper e slo-blo type.
2.2 CONTROLS AND TERMINALS (figure 2-2)
2.2.1 Fro" I Ponel
The function switch in the top center of the front panel selects one of four filtering
functions: Low Pass (LP), High Pass (HP), Band Pass (BP), or Band Reject (BR).
4
g
FRONT VIEW REAR VIEW
FIGURE 2-2. FRONT AND REAR PANELS
CD ®
POWER SWITCH (ON IOFF ) OUTP UT CONNECTOR (BNC TYPE)
® @
INDICATOR LI GHT INPUT CONNECTOR (BNC TYPE)
@INPUT CONNECTOR (BNC TYPE) @12 FUSE 1I/ /1B6AA SSLLOO--BBLLOO 2!l3T 4VV :(1.n)
® (,...'..l..
@
OUTPUT CONNECTOR (BNC TYPE) POWER RECEPTACLE o
...
®
@
MULTIPL IER SWITCH (HIGH PASS) CHASSIS GROUND CONNECTOR (BINDING POST) N
®
@
MULTIPLIER SWITCH (LOW PASS) GROUND SWITCH (FLOATING I CHASSIS) o
o
v
@
FREQUENCY DIAL (LOW CUTOFF) RESPONSE SWITCH (MAX FLAT I LOW 0) l't>
.-.t.
® @ .P.J..
FREQUENCY DIA L (HIGH CUTOFF) DC LEVEL POTENTIOMETER
::J
® @ ()Q
115 / 23 0V LI NE SWITCH FUNCTION SWITCH (LP, HP, BPt BR) 5'
...
til
....
c
...
(..'l..
Figure 2-2. Front and Rear Panels o
::l
VI
t1l
F ilter, 3550
The cutoff frequencies are set by dials and rnul t i pl i e r sw itches, one fUI' the High
Pass and one for the LLl\\ Pass sec ions.
The power ON switch and indicator light in the l ower center complete the front panel
controls .
BNC C onnectors fo r INPUT and OUTPUT are located in I he l ower corners.
2.2.2 Rear Panel
The RESPO SE switch provides choice be tween MAX FLAT and LO\.\,' 0 re sponse of
the Model 3550. The GROU. ' D switch, recessed in the rear panel to prev ent in ­
advertent operation, connects the chassis to circuit ground in t ne CHASSIS pos ition
and disconnects them in FLOATI G. The DC L EV EL multiturn screwd river - ad­
ju stable potentiometer permits setting of the output DC level. The LINE switch
selects 115V r 230V AC ope ration.
The INPUT and OUT PUT BNC connectors again occupy the corner s and the CHASSIS
binging post provides means for grounding the chassis.
A fuse holder labeled with the required fuse rating, is also mounted on the l' ar
panel.
2.3 OPERATING PROCEDURE
2.3.1 Connect the Mod el 3550 to the power line.
2.3.2 Make conne ctions to the INPUT and OUTPUT.
2.3.3 Set the function switch to the desired mode and the High Pass and Low Pass
section contro ls to the required frequency ranges.
2.3.4 T u r n ON pu\'.,'er.
NOTE
If the input signal exceeds the m axim um
specified levels (7v peak, ±IOOvdc) or if
the output current exceeds ±15m A pea
clipping will occur.
2.4 SPECI AL FUNCTIONS
2.4.1 Narrow Bon dposs
Narrowest passband in the band-pass mode is obtained by se tting both cutoff fre­
quencies equal as shown in figure 2-2, curve C. The res ulting insertion loss is
6