Heathkit V-4 User manual

HEATHKIT
MODEL V-4
VACUUM TUBE VOLTMETER
SPECIFICATIONS
Power Requirements: .
Overall Size:
Kit Shipping Weight: .
Meter:
Multipliers:
Power Supply:
Batteries:
D. C. Voltmeter: 6Ranges:
Input Resistance: .
Sensitivity: ....
Circuit:
Electronic AC Voltmeter: 6Ranges:
Circuit: .
Electronic Ohmmeter: 6Ranges: ..
.105-125V 50/60 Cycle AC, 10 Watts.
.10" high x6" wide x5-P deep.
.8pounds
4f"Streamlined case with 200 microampere move-
ment.
Carbofilm precision type--l% tolerance.
1-6SN7 Twin triode meter bridge.
1-6H6 Twin diode AC rectifier.
Power transformer and selenium rectifier.
2- li Volt standard flashlight cells.
.0-3, 10, 30, 100, 300, 1,000 volts full scale.
With accessory probe to 3,000 and 10,000 Volts.
.11 megohms (1 megohm in probe) on all ranges.
110 megohms with accessory probe.
3,666,666 ohms per volt on 3Volt range.
.Balanced bridge (push-pull) using twin triode.
.0-3, 10, 30, 100, 300, 1,000 Volts full scale on linear
scales reading R. M. S. (.707 of negative peak).
Diode with adjustable compensation.
,Scale with 10 ohms center xl, xlO, xlOO, xl,000,
xlOM, xl Meg. Measures .1 ohm to 1,000 megohms
with internal battery.

ASSEMBLY OF THE HEATHKIT
MODEL V-i
VACUUM TUBE VOLTMETER
It is not difficult to construct this instrument If the instructions are carefully followed. Do not
rush the construction, Take time to do afirst class job to Insure years of troublefree operation.
Hurried work increases the chances of mistakes and subsequent difficulties. THEREFORE READ
THIS MANUAL FULLY THROUGH BEFORE STARTING THE ASSEMBLY.
Begin by checking the parts against the parts list. Identify each part, using the charts on the
inside of the cover of this manual where necessary. Thus, you will avoid throwing away any small
part* with the packing,
Familiarise yourself with the layout by studying the pictorial diagram and the photo prints. Then
proceed by following the step-by-step assembly instructionSr
Read the note on soldering on the inside of the batik cover. Make a good mechanical joint of each
connection with clean metal to clean metal- Use only good quality rosin core radio type solder
.
Pastes or acids are difficult to remove and minute? amounts left combine with moisture from the
air forming acorrosive product. Weeks or months later corrosion may result fnuntimely fail-
ure. This corrosive product is also afairly good conductor and may cause short circuits which
damage the meter,
NOTE: ALL GUARANTEES ARE VOIDED AND WE WILL NOT REPAIR OR SERVICE IN-
STRUMENTS IN WHICH ACID CORE SOLDER OR PASTES AHL USED,
Small changes In parts may be made by the Heath Company. All parts supplied will work just as
well as the part for which It was substituted. All substitutions will be of equal or better quality
than the original fand will be made in order that aminimum delay will occur in filling your order,
The precision resistors are marked with K=1,000 and M=1,000,000, Thustaresistor marked
9QK =90,000 ohms and one marked G-9M =9,900,000 ohms or 9-9 megohms.
The chassis and panel are wired separately as far as possible. Then they are fastened together
and the wiring is completed-
step by Step assembly
(5) means solder the connection (NS) means do not solder yet
l. Fasten the tube sockets (OS4) with socket rings (04 3Jto
the chas Is (V52B) with the keywavs towards the nearest
edge of the chassis. The end of the ring can be held In
the groove in the socket and the rest of the ring can
then be forced over the socket and into the groove with
ascrewdriver. Mount the two calibrating controls (V 24)
with acontrol nut and a control loekwasher between
control and chassis- Temporarily mount the zeru ad-
just controMV03.) and the ohms adjust control {V25J with
acontrol nut and acontrol lockiwasher between control
and chassis. Mount the AC balance control (V99) with
acontrol nut and aconlrol loekwasher between control
and Chassis.
2- Install the three frubber grommets (035) In the chassis holes provided. Mount the power
transformer with the twolejid* through the groin met near the front and the? four leads through
ihe grommet near the rear of the chassis. .Between the tube sockets, use a 6-32 x%screw
with asingle terminal strip {Q38) and asolder lug under the nut. On the other side, uac a
G-32. x1screw, and place the selenium rectifier (V97) and aloekwasher under the nut.

Cut transformer leads to length and connect asfollows: One- yellow lead to solder lug (MS) be-
tween tube sockets- Other yellow lead lo pin 1/7 on SH6 socket {MS), One red lead to single
terminal strip (NS). Other red lead to lug on selenium rectifier nearest chassis (S). Abare
wire through pin #1 (3) fr2 (£) t'4 (NS) and tf& INS) on 6HG socket, Abare wire to pin #4 (NS)
on 6116 socket and to solder lug (NS)- Abare wire to pin CMS) on 6SN7 socket and to solder
lug (S). Awire to pin #7 on 0H6 socket (S), and to pin #7 on 6SN7 socket (NS), Awire to lug
on selenium rectifier farthest from chassis (NS) and through pin #5 (S) to pin +2 (NS) on 6SN7
socket,
A,003 condenser (V2<5) to pin #4 on 6H& socket (S),and with spaghetti over the lead to pin #4
on 6SN7 socket (NS). A47OK resistor (013) to pin #8 (S) and pin *6 (NS) on 6H& socket. A
10 meg resistor (CIO) to pin *5 (S) and to pin #3 {NS). A 20K resistor (V22)to single terminal
lug {NS), and to pin If 8on 6SN7 socket (NS). Ameg resistor (O10) to pin f1(S) and pin *&
(NS) on 6SN7 socket. A1SK resistor {V23) to pin #S <S> and to pin #3 {5) on 65N7 socket.
A2K Resistor (G15) to pin A3 on 65N7 socket (ft 5) and with spagetti over the lead to lower ter-
minal of aero adjust Control ($}. Aresistor {015) with spaghetti over both leads to upper
terminal o£ zero adjust control (Si and to pin KG on 6$N7 socket (NS). A47K resistor (A 10)
with spaghetti over both leads to center terminal of zero adjust control (5) and to single ter-
minal strip (NS). A5600 resistor (G12) to inward terminal of DC calibrate control (S), and to
pin #6 on 6SN7 socket (NS). Awire to inward terminal of AC calibrate control (S) and to pin
on 65N7 socket (£}. Awire to center terminal of ohms adjust control (5) and to center ter-
minal of DC calibrate control (NS), A12 MFD condenser (V27) with positive lead to lug on
selenium rectifier farthest from chassis (S) and with negative lead to single terminal strip (S).
Assemble battery bracket as shown and mount on the chassis
with the triple terminal strip and asolder lug under the nut, A
black transformer lead to lower lug {nearest chassis) on ter-
minal strip (NS). Awire to pin #6 on 6HB socket (S) and to out-
side terminal of AC balance control (S). Awire to pin #3 (NS)
on GH& socket and, to middle lug on terminal strip (NS). A.01-
l,00Ov condenser (024) toe enter terminal of AC balance control
(NS) and through solder lug {$) to battery bracket terminal
nearest roar edge of chassis (3). Two 1meg resistors (Ol7)
to center terminal of AC balance control (S), one to middle lug
(S) and other to upper lug (ft 5) on terminal strip. r.".P
On the panel (V 51 C), mount the pilot light assembly (039, O40, 041, 042, 052) with the bracket
toward the slide switch opening. Mount the slide switch (034) with 6-32 screws and nuts.
Mount the banana jacks with speedmits (044), the blackjack (V77B) in the hole marked common
and the red jack (V77R) in the hole marked AC Ohms. Push the banana jack inserts (M28) into
the jacks from, the front of the panel as far as they will go. Mount the phone jack (K17) with
acontrol nut using acontrol Lockwasher between jack and panel and anickel washer between
panel and nut. Mount the range switch (V75) to the panel with acontrol nut, using alockwasher
between switch and panel and anickel washer between panel and nut. Tighten nut partly. Tem-
porarily install apointer knob. Turn switch counterclockwise as far as it will go. Kow turn
the whole switch so the knob points at 3V -Rxl. Carefully remove knob and tighten nut,
...
,)
Q£f~fltL OFBAttAWA JACK. how TO mount catirfiai.5 istvj Tt/tES
Wire the range switch by mounting the multiplier resistors (V103, V73, V74, V6B,, V66, V65,
V71, V7Z and V70) as shown in the pictorials Note that the 30K resistor (V66)
connects to the grounded lug on the phone jack. The 8.3 resistor (VI 03) is soldered to the
switch without shortening the lead, after slipping on apiece of spaghetti. The other side v=
connected later.
Page %

G=fiJ
9,In stall the selector switch (V2 8A)with acontrol mit,using a c ontrol locfcwash er between switch
and panel and anickel washer between nut and panel. Make sure this switch ts mounted as
shown in the pictorial. Abare wife to black banana jack (SJ and to ground Lug on phone Jack
(B). Abare wire to one lug on pilot light (S) and to pilot light bracket (S),
10. Awire ta front outside lug on range switch (S) and to lug W3 oh front deck of selector switch
(5). Awire to lug on range switch to which 7meg resistor is connected (3) and to lug #9 on
front deck {nearest panel) ol selector switch (S). Awire to front inside lug on range switch
(S) and to lug #1 on front deck of selector switch {$}- Abare wire to insulated Contact on phone
jack (St and to lug #10 on front deck of selector switch- Awire to red banana jack (S) and. to
lug #5 on front deck ol selector switch (3),
11. Mount the meter (V4SC) on the panel with the hardware provided on the meter. Loosen the
nuts on the aero adjust and ohms adjust controls on the chass ia.Slip the panel oyer the bushings'
of these Controls and replace the nula using *nickel washer between nut and panel. Awire
to pin #7 on 6SN? socket (S) and to lug on pilot light aockai (5) Awire to lug #8 on front deck
of selector switch (S) and to upper lug on triple terminal strip (S). Awire to lug #8 on rear
deck (farthest from panel) of selector switch (S) and to nearest terminal of ohm sadjust control
(S), Awire to lug #1 on rear deck of selector switch (S) and to center terminal of DC calibrate
control (3). Abare wire to lug #6 on rear deck of selector switch (S) and tu pin *3 on 6SN7
socket (S). Awire to lug #5 on rear deck of se lector switch f$) and to center terminal of AC
calibrate control ($). Slip spaghetti over the lead on the 8.3 resistor from the range switch
^nd connect to nearest lug of battery bracket (S).
12. A3.3 meg resistor (010} with spaghetti Over both leads to lug #2 on front deck of selector
switch (S) and to pin #4 on 6SN7 socket (S). A.01 MFD>2,000V condenser <V79) with spaghetti
over both leads to lug *4 on Jront deck of selector switch (S) and to pin 03 on 0H6 socket (SJ r
A wire to lug on rear deck of selector switch fS) and through nearest grommet In chassis
to meter terminal nearest AC balance control ^3). Awire to lug #4 on rear deck of selector
switch (S) and through nearest prom met in chassis to meter terminal nearest tube sockets ($).
The remaining black transformer lead to upper lug on slide switch (S). Place the line cord
(078) through the grommet in the rear of the chassis. Tie aknot for strain relief and one
lead to lower lug on slide switch (S), other lead to lower lug on triple terminal strip (S). A
wire between the top lugs on the battery bracket (S),
13. Make up the test leads: The common lead is black test lead with ablack banana plug
(V39) on one end and an alligator clip (V44) on the other end- The AC ohms lead is red test
lead {V46) with ared banana plug (V4Q) on one end and ared test prod (V42) on the other end.
The DC lead is shielded test lead (V47) with a phone plug (V41) on one end and a small Imeg
resistor (V56) inside the black test prod (Y43), Prepare the cabinet (V53) by Installing the
handle (079) with 10-24 screws and by pushing the rubber feet (034) into the holes in the bottom.
Install the acorn knobs [V4%] on the adjust controls, and the pointer knobs (051) on the
switches.
//VSrAi.1 FFfr
AS Sffl)W^ PHOVG PLUG AWM&LY
Page 3

TEST AND CALIBRATION
Chock the wiring over carefully. We suggest tracing over each wire on the pictorial with acolored
pencil aait is checked on the instrument. Check each solder connection. Install the tubes.
Pluu into a)17 Volt 50/60 Cycle AC ONLY outlet. This Instrument will not operate and serious
damage will result if connected to DC-
Turn switch on and allow aminute for warm up. Set selector to DC +. Check operation ol sero
adjust Control- Turning this control should move the meter pointer to about half scale and to auro.
Set jioinlerto zero andchecluf it remains on iero when switched to DC -, If there is appreciable
zero shift (more than one division on the stale) the tubes must beaded. First complete the initial
iest rhowever.
Insert the common and DC test leads. Set the selector switch to DC +and the range switch to 3v.
Connect the calibrated flashlight cell and adjust the DC calibrate control so the meter pointer
indicates the calibration voltage on the 3V scale.
Install the batteries in the battery bracket as shown. Set selector
switch to ohms. Pointer should swin^ to about full stale. Turn, ohms
adjust to pive full scale reading (IN Finite). Insert AC ohms test lead.
Touch th.i* loud to common lead and observe pointer dropping to zero
indie at Ioil .short circuit (no resistance).
Temporarily remove AC ohms test lead. Set range switch to 3V and
selector to AC. Adjust AC balance control so no movement is noticed
in the pointer when .switching from AC through DC -to DC +, Now set
range switch to 300V, Re -insert AC ohms lead. Connect AC ohmsand
common lead lathe 117V AC line [NOTE: 117 Volt line is dangerous-
-
proceed with due care) and adjust AC calibrate control so pointer indicates the line voltage.
It is recommended that the tubes be aged before final calibration. This is accomplished by keeping
the instrument tumtd on for aperiod of at least 48 hours. Final calibration should be done in
the same way as the initial calibration. Careful calibration will result in amore accurate in-
si rum cut ,Ha standard AC meter is available, it is desirable to use such instrument, preferably
at avoltuge near full scale indication on the VTVM, as for instance 250 Volt or 90 Volt {on the
300V or 100V scale respectively).
After final calibration, install the instrument in the cabinet with sheet metal screws through the
panel and in the rear into the chassis. This completes the instrument.
CIRCUIT DESCRIPTION
This instrument uses abalanced vacuum tube circuit to increase the sensitivity and provide greater
flexibility. The relationship between the test voltage applied to the tube and the indicating meter
current is linear over arange appreciably greater than the operating range, When amuch larger
teat voltage is accidentally applied hthe relationship ceases to be linear and the indicating meter
current is limited to avalue of a few times full scale current. This makes the meter, when used
in. this circuit, virtually burn out proof. Repeated overloads should be avoided, however, as the
pointer may be bent.
The zero adjust control balances the currents through the tubes and permits the meter to be set
to aero, or partly up scale.
The calibration controls are in series with the meter and are adjusted to produce full scale reading
wLUi the proper test voltage applied to the instrument. The maximum test voltage applied to the
tube is about 3Volts, Higher test voltages are reduced by avoltage divider with atotal resistance
of 10 megohms. An additional resistor of 1megohm is located in the DC test prod, which permits
measurements to be made in circuits carrying K, F. with minimum disturbance of such circuits.
Pafje 4

For AC voltages in the Audio Frequency range, ashunt fed diode is used to provide aDC vyltage
proportional to the peak of the applied AC voltage. This DC voltage is applied through the voltage
divider to the tube, causing the meter to indicate* The AC calibrate control is used to get the
proper meter deflection the applied AC voltage rVacuum tubes develop a contact potential
voltage between tube elements, Such contact potential developed in the diode would cause aslight
voltage to be present at all ti meg- This voltage is cancelled out by bucking it with a. portion of
the contact potential of asecond diode. The amount of bucking voltage is controlled by the AC
balance control. This eliminates zero shift when switching from DC to AC.
For resistance measurements, a3Volt battery ig connected through astring of multipliers to
the tube. The external resistance to be tested is connected between tube and common {chassis),
forming, 'together with the multipliera, avoltage divider across the battery- The resultant portion
of the battery voltage is thus nop Iled to the tube causing the meter to deflect. The meter scale i&
calibrated in resistance.
The operating power for the lube is obtained from apower supply uging apower transformer, a
halt wave selenium rectifier, afilter condenser and avoltage divider,
The VTVM has many advantages over the non- electronic volt-ohm meters- The greatest advan-
tage is the high input resistance. This ejiables much more accurate readings to be obtained in high
impedance circuits, such as resistance coupled amplifier^ oscillator grid circuits and AVC net-
works.
To illustrate this, let us assume aresistance Cfupled audia amplifier with a-5 megohm plate load
resistor operating with a100 Volt plate supply, Let us also assume that the plate voltage is
50 Volts and that, therefore, the tube acts as a.5 megohm resistor. Measuring the plate voltage
with aconventional 1,0(30 ohm per volt instrument on the 100 Volt scale, the meter can bo con-
sidered a100,000 ohm (A megohm) resistor in parallel with the tube. The voltage on the plate
is then about HVolts and is shown as such by the meter. This is due to the shunt resistance of
the low resistance meter, Using the VTVM pn any scale getting >the full 11 megohm is placed in
parallel with the tube, The voltage on the plate is then about 43 Volts or 2% lower than the nor-
mal operating voltage. Thus accurate reading can only be obtained with the high resistance pro-
vided by aVTVM,
Similar benefits are obtained in AVC, oscillator and other high resistance circuits.
An understanding of the Characteristics of your instrument will result In greater satisfaction
through proper use-
UStNG THE VTVM
Page 5

DC VOLTAGE
To measure DC voltage with the VTVM> connect the common (black) lead to the common or "cold1'
side of the voltage to be measured. Set the selector switch to DC +or DC -as required ,and set
the range twitch to arange greater than the voltage to be measured;. If known. If unknown, set
to 1,000 Volts, With black test prod, touch other or "hot* side of the voltage to be measured, If
pointer moves less than one- third o( lull scale, switch to the next lower range,
AC VOLTAGE
To mrasure AC voltages with the VTVM, connect the common (black.) lead to the common or "told"
side ol the yo-Jtage to be measured- Set the selector switch to AC, and set the range switch to a
ranpe greater than the voltage to be measured, if known, tf unknown ,set to 1,000 Volts. With red
test prod, touch other or *hot" side oi the volume to be measured. If pointer moves less than
one -third of. full scale, switch to the newt lower range.
The Heathkit is an extremely sensitive electronic AC voltmeter and afi the human body picks up
AC when near any AC wires, the meter will indicate this pick up. Never touch the AC prod when
on the lower ranges. Zero should be set with the AC prod shorted to the common clip.
RESISTANCE
To measure resistance with the VTVM, connect the common (black) lead to one side oIthe resistor
to be measured. Set the selector to ohms, and aw* the range switch to such a range that the reading
will fall as near to mid scale as possible. Set the Ohms adjust control so the meter indicates
exactly full scale (INF, on ohm- scale). Then touch the red test prod to the other side ol the re-
sistor to be measured. Read resistance on ohms scale and multiply by the proper factor as shown
by the range switch setting.
CAUTION; Never leave the instrument on ohms, as it greatly shortens the life of the ohmmeter
battery
,
USING THE VTVM DECIBEL SCALE
Because the human ear does not respond to volume of sound in proportion to signal strength, a
unit or measure called the "belJJ was adopted. The "bel* is more nearly equivalent to human
ratios. Normally ihu reading is given in l/l0 of a^bel" or -decibel*.
Various signal levels arc adopted by various manufacturers as standard or "O" decibels.
The Heathkit VTVM DB scale uses astandard of S milliwatts into a5-00 ohm line as "0" decibels.
This corresponds to 1.73 VAC cm the 0-10 scale. From this figure, the various AC ranges of the
VTVM may be converted to db by the following chart.
AC VOLTS SCALE DECIBEL SCALE
0-SV- Subtract 10 db from reading
D-30V. Add 10 db to the reading
0-tOOV- Add 20 db to the reading
0-S0OV .Add 30 db to the reading
0-1 00OV .Add 40 db to the reading
As the decibel is apower rat ioor voltage ratio, it may be used as such without specifying the
reference level. Thus for instance, afidelity curve may be run on an amplifier by feeding in a
signal of variable frequency but constant amplitude. Ala reference frequency oi say 400 cycles,
adjust Input to give aconvenient indication (Odh for instance) on ihe VTVM connected to the output.
As the input frequency is varied, the output level variation may be noted directly in db above and
he low the sj>eciiied reference level.
NOTE: When measuring complex AC wave shapes, such as ripple, hum, distorted and square
waves, the Indication is 70 of the negative peak.
Page 6

READING IDE METER SCALE
The voltage markings t>n the range switch refer to the FULL SCALE reading. The scale is marked
0-10 and 0-30 for voltage. Oh the 3Volt range, read the 0-30 scale and drop the zero. On the
10 volt range, read the 0-10 scale direct. On the 3D Volt range, read the 0-3O scale direct. On
the 100 Volt range, read the 0-10 scale and add one zero. On the 300 Volt range, read the 0-30
scale and add one zero, On the 1,000 Voll range, read the 0-10 scale and add two zeros.
The resistance marking or ohms scale refers to the lowest resistance range (Rxl). For the other
ranges, add the proper number of zeros (add two zeros lor RxlOO, add four zeroslor RxlOM, add
six zeros for Rxl Meg). On the Rxl Meg range, the scale can also be considered to read directly
in megohms.
ACCURACY
The accuracy of most meters is rated al 2% of lull scale on DC and 5% of full scale on AC The
Heathkit VTVM easily full ills these requirements. When comparing with other instruments, con-
sideration should be given to the possibility that the other Instruments variation might be the
opposite of the HeatJikLt making apossible variation of 4& on DC and 10% on AC
IN CASE OF DIFFICULTY
1. Recheck the wiring- Most cases of trouble result from wrong or reversed connections. Often
having afriend cheek the wiring will reveal amistake consistently overlooked,
2. Check the tubes,
3. If the pointer swings lull scale to the right and slays there with switch set to DC +, check for
an open Circuit or high resistance connection someplace between the grid pin +4 of the
and ground, This might be due to awrong connection to the selector switches, poor connection
or possibly nr. open resistor.
II the instrument does not operate on any function, a check of the power supply, 6KNT and its
associated meter circuit is suggested.
If the instrument only fails to function on AC measurements, then acheck of the 6HS and Its
associated circuits is indicated-
if the instrument only fails to function on ohms, the difficulty will probably lie in the batteries
or the ohms multipliers.
Proper operation on DC should first be secured before an attempt is made to use the instrument
on AC Or ohms,
4. Check the operating voltages. The following voltages are measured to Chassis: Pin fi2 or #5
on 65N7 tube or +lug on rectifier 40-70 Volts positive. Single terminal striu 60-100 Volts
negative. Pin *7 On 6HG or 65N7 or "hot" lug on pilot light socket 5-6 Volts AC,
5. Check continuity through DC test Cable. Make certain that the shielding is not shorted to center
conductor,
6. Write to the Heath Company describing your difficulties and giving all possible details, such
as voltages obtained, meteT indications if any, model number etc. We will attempt to analyze
your trouble and advise you accordingly.
Page 7

7, If desired, your instrument may be returned to the factory. The Heath Company will check it
and put it in operating condition for acharge of £3.00 plus any parts or alterations required
due to damaged or improper construction,
NOTE: Before returning your instrument, make sure ail parts are securely mounted, and that all
eight screws (including the tines in the rear) holding; the instrument in the cabinet are tight. Attach
atag with name, address and trouble experienced to the instrument. Include the test leads- Pack
instrument in arugged containertpreferably wood, using at least three inches of shredded news-
paper or excelsior on all sides. Do not use loided newspapers. Do not ship in original carton
only- Ship by prepaid express if possible, Upturn shipment 'will be made by express collect.
NOTE that acarrier cannot be held liable for damage in transit if packing, in HIS opinion, is in-
sufficient,
BIBLIOGRAPHY
Many excellent articles on the construction and use of vacuum tube voltmeters have appeared Let
radio magazines Afew are;
RADIOCRAFT, June, 1945 TElectronic Ohmnicheeker
RADIO NEWS, January, 1847, Home Constructed VTVM
RADIO NEWS, July, 1&46, Vacuum Tube Voltmeter
RADIO NEWS, November, 1B45, Electronic Volt -ohmmeter
RADIO NEWS, February, 1046, Universal Test Instrument
RADIOCRAFT, May, 1945, Practical VTVM
VACUUM TUBE VOLTMETERS, ABook by John F. Rider
I?F TEST PROBE KIT
Atest probe in kit form for use in measuring RF voltages of up to about 20 Volts is available for
$6.50. Thekit contains all parts necessary for the const ruction of the probe, including IN 34 crystal
detectorTcondensers, resistor, cable and connectors, This probe and cable is simply plugged into
the instrument Inplaceof the regular DC test probe assemblyand is read on the lower regular DC
ranges.
Order No. 309 RF Test Probe Kit-- $6. BO.
TELEVISION TEST PROBE KIT
Atest probe in kit formfor use in testing the high DC voltages in Television receivers up to lO fOQQ
Volts is available for $4.50. The kit contains all parts necessary for the construction of the probe,
including precision multipliers of t% accuracy, cable and connectors. This probe and cable Is
simply plugged into the instrument in place of the regular DC test probe assembly and 0-10,000
Volts is read on the 0-10 scale. With ran^e switch set at 300V the full scale indication is 3000
Volts, Order NO- 310 TV High Voltage Probe Kit ~$4 .50.
Prices subject to change without notice. The Heath Company reserves the right to change the de-
sign of its instruments without incurring liability for equipment previously supplied.
WARRANTY
The Heath Company limits its warranty on any part supplied with any Heathkit {except lubes, meters,
and rectifier 5, where the original manufacturer's guarantee only applies) to the replacement within
three (3J months of said part which, when returned with prior permission, postpaid, was in the
judgment of the Heath Company, defective at the time of sale.
The asse mbler is urged to fol low Ihein strut tio ns exnt tly as provided. The Hoaih Company assum es
no responsibility for the operation of the completed instrument, nor liability for any damages or
injuries sustained in the assembly or operation of the dovtce-
HEATR COMPANY
Renlon Harbor, Michigan
Page 8

V-4 VACUUM TUBE VOLTMETER PARTS LIST
Part Parts
Ho. Per Kit Description.
Resistors
V103 ft 1n-lrm "Prj=v 1qinn Jl lJ v* JUIti1*7v to iuri
V7f1 GO Ohm PrdV ic1i-fcn
\f J1J J LJ. J1_LlaLUIL
V74 JUL* "UN 1411, fl cv4^LUII
VnY< Qfl-fUl Ohm Prpr i^inn
J|UVJ H-f J1J11jJCL LrMt^JJ
VV*J Tfl fifbfi fhhni Dr<w>ivinn 0hJ .ULPU Un 111 rTtJC 1nlQjl
jU" !IIITU1Uij IT1 Jrjtr4_ lblvn
^llft ftftfl rt>.Trt L>T>-.Z.i— .T-H i-i -p.
V7f!
VJuPlTUjUlTU kJTJ fl Ll-TCMJ IJtHHT,
V71
Til;. Vt'm£ri\\-i i>~i TJt1fir1icii i— Ki £m ivlu^ui UN rl BnltrJI
fJVlC|J.UJ] IIL KrCL Lt>i Uil
V70 "s hil j;ri-i S-j y. ,"Dm£j j k 11— |i ,-,
l- ._LPJ1_ ^LJLJL J 1JT^ J. C_E.jJL.JJI
.1 . w1xtXfi/ yJii |] 1
G12
V23-
V22 Lf jvWk>El LjJ
AID d7 unci fihm
OIB 470,000 Ohm
on 1Megohm
V56 lMegohm (Small)
010 3.2- Megohm
CIO 10 Megohm
Condensers
V2G .003 MFD Mica
024 .01 MFD 1,000V Paper Tubular
V78 -01 MFD 2,000V Paper Tubular
V27 12 MFD 150V Electrolytic
Cant mis and Switches
V24 2*5,000-10,000 Ohm Control (AC and
DC C^libTateJ
V25 *5,000-10,000 Ohm Control (Ohms
Adjust)
V63 13,000 Ohm Control (Zero Adjust)
V99 1Megohm Contrpl (AC Balance)
V2«A Selector Switch
V75 2pole fl paa. Switch.
004 SPST Slide Switch
Sockets, Terminal Strips and Jacks
OS4 Octal Snt:kE»ts
04;j 2Sockel Rings
04 0PLlut Light Nut
Oil Pilot Light Bushing
042 ^ilOL Light .lywEfi
052 Pilot Light Socket
03& Single Terminal Strip
SG25 Triple Terminal atrip
V102 Battery Term. Strip Assy.
V77R Banana Jack (red)
V7 7IJ Banana Jack {black)
M2C 2Banana Jack Inserts
K17 1Plione Jack
Pan p-irtH
No, Per Kit Description
Tubes and Limps
V31 16H6 Tube
G44 1SSN7 Tube
039 J#47 Pilot Bulb
Wire and Plugs
OT7 1Roll Hookup Wire
mi 1Length Spaghetti
V4C 1Length Red Test Lead
V45 1Length Black Test Lead
V47 1Length Shielded Test Lead
078 1Line Cord
V40 IRed Banana Plug
V39 1Black Banana Plug
V41 ]Phone Plug
V42 1Red Tost Prod
V43 1Black Test Prod
V44 1Alligator Clip
Hardware
031 6-32 xiScrews
26-32 x IFiat Head Screws
lB4fl ]k1Screw
S2£ &6-32. Nuts
TS72 G#6 Lock Washers
037 2Solder Lugs
O102 S*6 Sheet Metal Screws
O30 2#10-24 xIHandle Sc rews
033 8Control Nuts
oioi is Control Lock Washers
03* 5Control Nickel Washers
044 2Speednuts (or Jacks
035 3fRubber Crommets
03-1 4Rubber Feet
VS4 1Battery Spring Clip
V90 1Rattery Spring Bracket
VHJ1 1Stiffener Bracket
Miscellaneous
V4 0 2 Acorn Knobs
051 2Pointer Knt>bm
V49C 1200 Microamp, Meter
V2A 2Flashlight Cells (one cglitar
V^7 Selenium Ructiiier
V9fl Power Transformer
V51C Panel
V52B Chassis
V53 Cabinet
079 Handle
V4 Manual
*V24 and ¥25 Controls may be supplied in any value between
5,000 ohm and 10,000 ohm.
Page 0

HE ATM KIT
VACUUM TUBE
VOLTMETER
MODEL V-4
tffftf<*9 vets

HEAT HK.I T
VOLTMETER
MODEL V- *j