Heathkit BT 1 Service Manual

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HEATHKIT
MODEL BT-T

BATTERY TESTER

SPE CIFICATIONS
Test Ranges: ........... . ....... ........ 0 to 15 volts
0 to 180 volts.
Load Current: . ....... . . . . . . . . . . ........ A-BATT. Range 100 ma.
B-BATT. Range 10 ma.
Meter Indication: . . . . . . . . . . . . . .. ......... GOOD - WEAK - REPLACE
Size: .................. 5 7/8" longx3 widexZ 3/4" high

Shipping Weight: . . . . . . . . . . ............... 3 lbs.

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ASSEMBLY AND OPERATION OF THE
HEATHKIT BATTERY TESTER BT-I

The Heathkit Battery Tester provides a rapid, easy method of determining the condition of all
commonly used dry batteries. Each battery is tested under proper load conditions. The three
color meter scale shows the actual condition of the battery as it is when in use.

Two ranges are available; one for lower voltage "A" batteries, the other for higher voltage B"
batteries. The tester is used in the A-BATT. position when testing flashlight, lantern, radio
A", ignition and other heavy duty batteries. In this position a higher load current is drawn to
simulate the actual working conditions. The B-BATT. range is used for high voltage, low out-
put current hearing aid and radio "B" batteries, etc. This range is also used when testing
some low voltage, light duty cells. Examples are penlight cells, small hearing aid"A"batteries
and mercury cells.

USING THE HEATHKIT BATTERY TESTER

To test a battery the slide switch must be set for the proper type. Next the pointer knob is ad-
justed to the voltage rating of the battery. With these adjustments made, the black lead is
touched to the negative terminal and the red lead to the positive terminal of the battery. The
meter reads directly the condition of the battery.

The meter calibration on the BT- 1 is adjusted to show a battery weak when its terminal voltage,
under load conditions, drops to between 70% and 90% of rated voltage. When the terminal voltage
drops below 70% of rated value, the meter indicates replacement. These general ranges will
apply to most batteries in use.

Certain specific applications may not allow dry batteries to be used as fully. As an example, a
person with asevere hearing condition may have to replace batteries which still indicate "weak"
while another person with a less severe hearing condition can use the same batteries until they
show replace" on the tester. In such cases, the user can determine by experimenting what
meter indication represents the replacement point for his particular use.

INSPECTING THE KIT
Upon receiving the kit, immediately check each part against the Parts List. In this way you will
become familiar with the various components and also, it will prevent throwing away any small
parts with the packing.

Should inspection reveal the necessity for replacement of a component, write to the Heath Com-
pany immediately. The following information should be supplied in all cases:

A. Clearly identify the part in question by using the part number and description found in the
manual Parts List.

B. Identify the type and model number of kit in which it is used.

C. Mention the order number and date of kit purchase.

D. Describe the nature of the defect or the reason for requesting replacement.

The Heath Company will promptly supply the necessary replacement. Please do not return the

defective component until specifically requested to do so. Do not under any circumstances dis-
mantle the component in question as this will void the guarantee.

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