Krohn-Hite 7600 Operating instructions

Model 7600(M)/7602(M)
Wideband Power Amplifier
DC to 1MHz
141V/282V rms
17/34 Watts
Operating and Maintenance Manual

Service and Warranty
Krohn-Hite Instruments are designed and manufactured in accordance with sound engineering practices
and should give long trouble-free service under normal operating conditions. If your instrument fails to
providesatisfactoryserviceand youare unabletolocate thesourceoftrouble, contactourService Depart-
ment at [phone], giving all the information available concerning the failure.
DO NOT return the instrument without our written or verbal authorization to do so. After contacting us,
we will issue a Return Authorization Number which should be referenced on the packing slip and pur-
chase order. In most cases, we will be able to supply you with the information necessary to repair the in-
strument,avoidinganytransportationproblemsandcosts.Whenitbecomesnecessarytoreturntheinstru-
ment to the factory, kindly pack it carefully and ship it to us prepaid.
All Krohn-Hite products are warranted against defective materials and workmanship. This warranty ap-
plies for a period of one year from the date of delivery to the Original Purchaser. Any instrument that is
found within the one year warranty period not to meet these standards, will be repaired or rep laced. This
warrantydoesnotapplytoelectrontubes,fusesorbatteries.Nootherwarrantyisexpressedorimplied.
Krohn-HiteCorporationreserves theright tomake designchanges atany timewithout incurringany obli-
gation to incorporate these changes in instruments previously purchased.
Modificationstothis instrumentmustnot bemade without the writtenconsent of an authorized employee
of Krohn-Hite Corporation.

Model 7600(M) and 7602(M)
Wideband Power Amplifier
DC to 1MHz, 17W and 34W
Serial No. ___________________________
Operating and Maintenance Manual
15 Jonathan Drive, Unit 4
Brockton, MA 02301-5566 U.S.A.
Tel: [phone]; Fax: [phone]
Email: [email protected]
Service: ser[email protected]
www.krohn-hite.com
Copyright 2004 Krohn-Hite Corporation. All rights reserved.
Contents of this publication may not be reproduced in any form
without the written perrmission of Krohn-Hite Corporation.
Printed 5-04, Rev 3.1

Model 7600M ("M" is the Meter Option Package)
Model 7602M ("M" is the Meter Option Package)
Model 7600
Model 7602

Table of Contents
1.0 GENERAL DESCRIPTION ···························1-1
1.1 INTRODUCTION···································1-1
1.1.1 Shipping to Krohn-Hite for Repair or Calibration..........1-1
1.2 SPECIFICATIONS ··································1-1
1.2.1 OUTPUT (All rms values are for sinewave signals).........1-1
1.3 INPUT··········································1-3
1.4 GENERAL ·······································1-3
1.5 OPTIONS········································1-4
2.0 OPERATION ····································2-1
2.1 INTRODUCTION···································2-1
2.2 POWER REQUIREMENTS·····························2-1
2.3 TURN-ON PROCEDURE ······························2-1
2.4 OPERATION······································2-3
2.4.1 Front Panel ..................................2-3
2.4.1.1 PowerSwitch·······························2-3
2.4.1.2 Mode ···································2-3
2.4.1.3 AC/DCCoupling·····························2-3
2.4.1.4 GaindB··································2-4
2.4.1.5 VariableGaindBControl·························2-4
2.4.1.6 DCOffset·································2-4
2.4.1.7 VariableDCOffsetControl························2-4
2.4.1.8 MeterSelectSwitch(MeterOption) ···················2-4
2.4.1.9 Connectors ································2-5
2.4.1.10 OutputDisconnect/ConnectSwitch···················2-5
2.4.1.11 LEDIndicators ·····························2-5
I

2.4.2 Rear Panel ...................................2-5
2.4.2.1 Option002Connectors··························2-5
2.4.2.2 Chassis/FloatingGroundSwitch ·····················2-5
2.4.2.3 FuseReceptacle ·····························2-6
2.4.2.4 ACPowerReceptacle ··························2-6
2.4.2.5 LineSwitches ······························2-6
3.0 INCOMING ACCEPTANCE···························3-1
3.1 INTRODUCTION···································3-1
3.2 TEST EQUIPMENT REQUIRED ·························3-1
3.3 INCOMING PROCEDURE ·····························3-1
3.3.1 DC Offset and Peak Volts Meter Calibration Check.........3-1
3.3.2 Squarewave Broad Banding Check ...................3-2
3.3.3 Squarewave Rise And Fall Time Check.................3-3
3.3.4 Slew Rate Check ...............................3-3
3.3.5 Gain Calibration Check ..........................3-4
3.3.6 Frequency Response Check ........................3-4
3.3.7 1K Load Maximum Power .........................3-5
3.3.8 Distortion Check...............................3-6
ii

SECTION 1
GENERAL DESCRIPTION
1.1 INTRODUCTION
The Model 7600 and 7602 are 17 watt and 34 wattwideband power amplifiers that offer extended output
power and voltage capabilities, low distortion, versatility and the latest in hybrid CMOS power opera-
tional amplifier technology, with performance features not available in other power amplifiers.
Theunitprovides17wattsofcontinuous power(34wattsatdc)and141Vrmsfromdcto500kHz.Thefre-
quency response is ±0.1dB to 10kHz, and the distortion contributed by the amplifier is <0.01% to 5kHz
and<0.3%to 100kHz.The voltagegain canbe eitherinverting ornon-inverting and hasselectableranges
from0dBto14dB,14dBto 28dBand28dBto42dB(avoltagegainstepof5),andiscontinuouslyvariable
between the ranges.
Otherfeaturesinclude:modesofA,A–Band–B;commonmoderejectionof80dB;inputcouplingof acor
dc; a meterthatis selectableto display heat sink temperatures in °C, outputpeak voltageand average out-
put current. A dc offset control is also provided that is variable from 0V to ±200V.
TheModel7602providesthesamecapabilitiesastheModel7600but alsoprovidesabalanced outputand
isableto deliver 34 watts of continuous power (68 watts at dc), and 282V rms (800V p-p). It can also pro-
vide plus and minus voltages simultaneously.
Claim for Damage in Shipment to Purchaser
The Model 7600 and 7602 are carefully inspected, tested and aged before shipment to ensure that it is
working properly. The unit should be thoroughly inspected immediately upon arrival to purc haser. All
itemsshippedshould bechecked againstthe enclosedpacking list. Krohn-Hitewill not beresponsible for
shortages against the packing list unless notified immediately. If for some reason the instrument is not
workingproperly,orappears tohave beendamaged inshipment,inform thefreight carrierandfilea claim
for the damage, then notify Krohn-Hite or its nearest sales office immediately (to obtaina quotation to re-
pairtheshipmentdamage).Thefinalclaimandnegotiationswiththecarriermustbecompletedbythecus-
tomer.
1.1.1 Shipping to Krohn-Hite for Repair or Calibration
All shipments of Krohn-Hite instruments should be made via United Parcel Service or “Best Way” pre-
paid.The instrumentshould beshippedintheoriginal shippingcontainer; orif notavailable, use any suit-
able container that is rigid and of adequate size. If a substitute container is used, the unit should be
wrapped in paper and surrounded with at least four inches of shock-absorbing material.
Model 7600/7602 Section 1 - General Description
1-1

1.2 SPECIFICATIONS
1.2.1 OUTPUT (All rms values are for sinewave signals)
For the Model 7602, specifications apply to each output to ground.
Frequency Range: dc to 1MHz.
Power
1k Ohm Load: 17W rms, 34W dc and peak, dc to 500kHz; 5W rms to 1MHz.
600 Ohm Load: 10W rms, 100Hz to 1MHz; 5W rms, 10W dc and peak, dc to 100Hz.
Voltage
No Load: ±200V dc and peak, 141V rms.
1k Ohm Load: ±184V dc and peak, 130V rms, dc to 500kHz; ±113V peak, 80V rms at 1MHz.
600OhmLoad:±113Vpeak,80Vrms,100Hzto1MHz;±78Vdcandpeak,55Vrms,dcto100Hz.
Current: 910 ohm load, ±200mA peak, 141mA rms, dc to 500kHz.
Frequency Response: ±0.1dB, dc to 10kHz; ±0.25dB to 200kHz; ±0.5dB to 500kHz, 0-130V rms;
±0.5dB to 1MHz 0-80V rms.
HarmonicDistortion:<0.01%to5kHzand175Vpeakoutput;<0.05%to200Vpeak;<0.3%to100kHz.
Voltage Gain: 0dB to 42dB in three ranges; 0dB to 14dB, 0dB to 28dB, 0dB to 42dB; continuously vari-
able between ranges.
Step Accuracy: ±0.1dB plus frequency response specification. Gain steps are 14dB at max variable
gain control setting or a voltage gain of 5.
Stability: <0.001dB change for a 10% change in line voltage.
Dynamic Range: >80dB.
Hum and Noise (2MHz bandwidth): referred to output, <10mV rms; <20mV rms on the 0dB to 42dB
gain range.
Phase Shift: A input 0° ±1°, B input, 180° ±1° dc to 10kHz increasing linearly 60° lagging at 1MHz.
Model 7602: (Inverted output relative to non-inverted) 180°, –0.3° at 10kHz; 180°, –3° at 100kHz; 180°,
–20° at 1MHz.
Squarewave Response
Rise/Fall Times: 120ns to 50Vp-p.
Slew Rate: >600V/ms, 400Vp-p.
Aberrations: <5%.
Section 1 - General Description Model 7600/7602
1-2

Regulation: <0.1%, No load to 1k ohm load, dc to 10kHz, rising to 2% at 1MHz.
Coupling: DC.
DC Level: Nominal zero volts; vs. temperature, 2mV/°C.
DC Offset Control (no load): 0V to ±200V.
DC Level Stability
Vs. Line: <1mV for a 10% change in line voltage.
Vs. Temperature: <0.01%/°C or 2mV/°C whichever is greater.
Internal Impedance: <0.5 ohms, dc to 10kHz; 5 ohms at 100kHz; 20 ohms at 1MHz.
OutputProtection:Protected from overloads with a uniquefoldbacklimiterwhichkeeps theoutput cur-
rent within safe operating regions. Kickback diodes clamp kickback voltages to the supply.
1.3 INPUT
Modes: A, A–B, –B.
Maximum Voltage (without damage): ±200V dc referred to ground.
Maximum Common Mode: 0dB to 14dB range, ±200V peak; 14dB to 28dB range, ±40V peak; 28dB to
42dB range, ±8V peak.
CommonModeRejection:80dB,dcto200Hz;60dBto1kHz;40dBto10kHz;risingto20dBat1MHz.
Sensitivity: ±1.6V peak.
Coupling: Direct (dc) or capacitive (ac) with low frequency cutoff of approximately 1Hz.
Impedance: 1Megohm inparallel with30pF withfront inputsonly; 65pFwith frontand optional rear in-
puts, independent of input gain setting.
1.4 GENERAL
Load Impedance: Capable of driving any resistive load within the current and voltage limitations of the
amplifiers foldback limiter. Capable of driving reactive loads within voltage and current limitations.
Temperature Range: 0°C to 45°C.
Controls
Front panel:Power switch, 5-position input MODE switch, 2-position INPUT COUPLING switch,
3-position GAIN controlswitch, variableGAIN dBpotentiometer, 10-turnvariable DCOFFS ET po-
tentiometer, 3-position offset RANGE switch, 4-position METER SELECT switch, output CON-
NECT/DISCONNECT switch.
Rear panel: CHASSIS/FLOAT GROUND switch.
Section 1 - General Description
1-3

Front Panel Warning LED Indicators: Over TEMP, CLIPPING, output H.V. (high voltage).
Terminals: BNC A input, BNC B input, binding post output.
Rear Panel: Power receptacle, optional BNC A input, B input and binding post output.
Power Requirements: 90-132/198-264 volts, 50Hz-400Hz, 200 watts.
Dimensionsand Weights: 312“ (9cm) high, 812” (21.8cm) wide, 18" (46ttttttttt.2cm) deep; 12 lbs (5.4kg)
net, 14 lbs (6.3kg) shipping.
Accessories: 3-terminal line cord, operating manual.
1.5 OPTIONS
7600M/7602M Meter - Option Package
HeatSink Temp °C: Measuresthe heatsinktemperaturein thevicinityoftheoutputpoweramplifier
IC. Used as an indicator of operating conditions and air flow to the unit.
Output Peak Voltage: Measures the largest peak voltage independent of polarity with a 1 second
time constant.
Accuracy (at 1kHz): ±0.5V.
Frequency Response: ±2%, 10Hz to 100kHz; 5% to 1MHz.
Average Output Current: Measures average dc supply current delivered to the output amplifier as
an indicator of output amplifier load. Quiescent current is nulled out. Can be used to find resonances
in a load.
Accuracy: ±5% ±1 digit.
Rack Mounting Kit: Part No. RK-37, permits installation of the Models 7600/7602 into a standard 19"
rack spacing.
Option 003: Rear panel input and output connectors.
Section 1 - General Description
1-4