Heathkit HR 1680 Manual

Page 1

for the

SSB/CW RECEIVER
Model HR-1680

595-1830-08 L

HEATH COMPANY - BENTON HARBOR, MICHIGAN

Page 2

Heathkit® Manual

for the

SSB/CW RECEIVER
Model HR-1680

595-1830-08

Copyright © 1976

H EAT H c o M PA N v Heath mm

All Rights Reserved
BENTON HARBOR, MICHIGAN 490 2 2 Printed in the United States of America

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Page 2 _I-IEATHKIT@
TABLE OF CONTENTS
UNPACKING ........................................ 3 OPERATION ....................................... 81
Typical Operating Characteristics ................. 82
PARTS LISTS ....................................... 4
VFO Circuit Board ............................... 5 IN CASE OF DIFFICULTY
HFO/XTAL Calibrator Circuit Board ................ 6 Visual Checks .................................. 83
Front End Circuit Board .......................... 6 Precautions for Troubleshooting .................. 84
AUD/ REG Circuit Board ....................... 9 Checking Transistors and Diodes ................. 84
Chassis ........................................ 12 Troubleshooting Charts .......................... 85
ASSEMBLY NOTES .......................... I ..... 14 SPECIFICATIONS .................................. 88
CIRCUIT BOARD ASSEMBLY ....................... 16 CIRCUIT DESCRIPTION
VFO Circuit Board ...................... 17 Front End Circuit Board .......................... 90
HFO/XTAL Calibrator Circuit Board ............ 22 AUD/REG Circuit Board . . . ............. 91
Front End Circuit Board ..................... 27 VFO Circuit Board ........................... 92
AUD/REG Circuit Board ......................... 33 HFO/XTAL Calibrator Circuit Board ............. 93
Other Circuits .................................. 93
CHASSIS ASSEMBLY ............................... 42
CIRCUIT BOARD X-RAY VIEWS ..................... 94
INITIAL TESTS
Resistance Checks .............................. 66 IDENTIFICATION CHARTS
Voltage Checks .............. .. i Diodes ......................................... 98
Sound Check ................................... 70 Transistors ............................ 99
Integrated Circuits ............. i ............... 100
ALIGNMENT ....................................... 71 SCHEMATIC ................................... Fold-in
CABINET ASSEMBLY ............................... 78 WARRANTY .......................... Inside front cover
INSTALLATION ..................................... 79 CUSTOMER SERVICE ................. Inside rear cover

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m-

( ) 0401:2N5770translstor(#417~293).
Refer to Detail D.

( ) C408: 24 pF mica.

( ) 6412:47 pF mica.

( )0415: 100 pF mica.

( )C416: 100 pF mica,

( ) Q40222N5770iransistor(#417-293).
Fleier to Detail D,

( ) Solder the leads to the loil and cutoff
the excess lead lengths.

( )0425: Install the 8-60 pF trimmer
capacitor as follows:

1. Flefer to the illustration below and
identity the end oi the top trimmer
plate.

2. lnsertthe lrimmer lugs Into the cir~
cuit board so the end of the top
plate is toward the right as shown.

3. Push the trimmer down against
the circuit board. Then bend the
lugs overilatagainstthectherside
oi the circuit board.

4. Solder the lugs to the loll.

END OF
TOP

TRIMMER PLATE
QC?)

-I-IEATI-IK

When you Install a coil on the board. posi-
tion it over its outline. making sure all four
coll pins are inserted through the board
holes. Then solder each pin.

( ) L401: 0.5 [LH coil (#40-687, green
dot).

( ) L402: 05 [AH coll (#404587. green
dot).

( )L403: 0.5 MH coil (#40-687, green
dot).

( ) L404: 0.5 pH coil (#40-687. green
dot).

( ) L405: 05 H coil (#40-687. green
dot).

( ) L406: 1.42 pH coll (#404047, gray
dot).

( ) PCB pin at TP. Fteier to Detail F.

( )Q403: MPSAZO transistor (#417-
801). Refer to Detail D.

) 0404: MPSA20 transistor (#417»
801). Reier to Detail D.

PICTORIAL 2-3

( ) Use a small screwdriver to turn the
screw in trimmer capacitor C425
down snug. DO NOT FORCE. Then
turn the screw one turn coun-
terciockwise.

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_HEATI-IKIT®

-

NOTE: The lollowing toroid coils can be in-
stalled only one way in the circuit board.
Solder the lugs 01 each coil to the toil as you
install it.

( ) L118: 22 [LH toroid coll (#40-1 805)

( ) L117: 2.2 #H toroid coil (#40-1805).

( ) L116: 22 aH toroid coil (#404805),

( ) Reter to Detail H and install ferrite
beads in the live locations shown.

( ) Solder the leads to the loll and cut oft
the excess lead lengths.

NOTE: When you install the following toroid
coils, be sure to position the color dot on the
coil as shown by the dot on the circuit board.
Solder the lugs of each call as you install it.

( ) L109: 10 MH toroid coil (#40-1789).

( ) L108: 1.8 pH toroid coil (#404788).

( ) L107: 4.7 ,LLH toroid coil (#404737)

( ) L106: 13 pH torold coll (#40-1786).

( ) C155: Install a 1-8 pF trimmer on the
col! at L106. Bend the trimmer lugs so
they touch the two indicated coll lugs.
(These are the lugs on the side at the
coll away from the color dot.) Then
solder the trimmer lugs to the coil
lugs.

TRIMMER

SOLDER
\

PICTORIAL 3-3

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W-

lnstall ilve 1-8 pF trimmer capacitors at the
lollowing locations, These trimmer
capacitors may be installed either way in the
circuit board. Solder the lugs to the toil as
you install each capacitor.

( ) c131.

( ) 0125.

l ) c125.

( ) C123.

( )c119.

( ) PCB pin at A. Refer to Detail F

( ) RFC101:350;1.H RFchoke (#45-32).
Refer to Detail B,

( ) Solder the leads to the toil and cutoff
the excess lead lengths.

( ) Cuta large letter A" from the terminal
identification label and remove the
adhesive backing, Press the letter
onto the circuit board at the location

shown,