TRANSNATIONAL RESEARCH ASSOCIATES

[Technical and Scientific Communication]

Elenco Electronics Cassette Player -- Model AK-200 /TR-18K

Repair and Replacement Procedures for Tape Deck Assembly

Art Madsen, M.Ed.

Introduction

Model AK-200/TR-18K is a simple battery powered Cassette Tape Player designed for voice recording and portable use by business personnel and journalists. The Tape Deck Assembly occasionally requires repair or adjustment due to rough handling, jarring or dropping of the unit. These repairs are not difficult and can be successfully accomplished by the owner.

Description of Equipment and Theory of Operation

The Tape Deck Assembly features three main parts, namely the Drive Train, the Push-Button Controls and the Tape Heads. Repair is usually focused on the first two components of the Tape Deck Assembly, since the Tape Heads are factory-sealed units seldom damaged.

The Drive Train is comprised of a motor turning at a constant speed. This motor powers a drive belt linked to a large ‘pinch-roller equipped’ pulley, all of which turns a capstan. The capstan holds both the large pulley, driving the feed reel, and a smaller pulley, linked by another drive belt, serving as a take-up reel. The large pulley pulls the tape across the tape heads at a non-fluctuating speed as the take-up reel holds tape that has been previously passed across the head. The take-up reel is equipped with a slip clutch to allow it to turn at various speeds as its load increases.

The Three Push-Button Controls consist of a PLAY function, a FAST FORWARD control and a STOP button. The play function button activates the audio, the motion controls and the motor, whereas the fast forward function disengages the slip clutch allowing the tape to whisk rapidly forward. The stop function deactivates all functions and, when pushed twice, releases the cassette from the body of the player.

The Tape Heads, which do not require repair under most circumstances, convert the magnetic properties of the tape to an electrical signal, on the basis of the principles of ferromagnetism. They do, however, require periodic cleaning with alcohol.

Repairable or Replaceable Components and Equipment: I. Control Button Assemblies and II. Drive Train

I. Stop Function Button Assembly

Fast Forward Button Assembly

Play Button Assembly

II. Capstan Assembly

Large Pulley

Large Drive Belt

Small Pulley

Small Drive Belt

Motor Case and Unit

Red Wires

Internal On Switch

 

Troubleshooting

Several symptoms of malfunction pertaining to the Control Button Assemblies and the Drive Train mechanisms are obvious to the owner. If one reel is functional and the other is not, a broken drive belt may be at fault. If the main capstan or motor seems inoperative, the problem could be the main drive belt or a burned-out motor, replaceable by direct order from Elenco.

It is best to remove the plastic casing and examine visible red wiring connections, pulley drive belts and positioning of control buttons to determine if jarring has dislodged any of these components. Reference to Figure 1 is important to properly understand the functional positions of these components.

The following Groups of Steps for Repair and/or Replacement of any of these drive train or button assembly components are offered for your convenience in personally attending to the most common malfunctions. There is no danger of electric shock, since the entire system operates on only 3 Volts.

Incidentally, please make sure that batteries are energized, contacts are clean and that electricity is reaching the player before resorting to these repair measures.

FIGURE I

Repair and Replacement Directions

(For all 24 replacement / repair steps presented below, refer to Figure One above for visual reference)

I. All three Control Button Assemblies are self-contained units, but may be knocked out of position by mishandling of the cassette deck. First, remove the cassette player’s plastic casing, by gentle prying at the groove provided on the left and right ends of the unit. Repair or repositioning of each Button Assembly differs slightly as follows:

II. For repair or replacement of the Drive Train, the following inspection and adjustment steps must be performed.

Capstan Assembly

Large Pulley & Drive Belt

Small Pulley and Drive Belt

Motor Case and Unit

Red Wires and Internal "On" Switch

The foregoing steps should alleviate approximately 75% of all electro-mechanical problems with your Elenco AK-200/TR-18K Cassette Player. If you are still experiencing problems, please send the entire unit, with a brief description of the problem, to our factory in Wheeling, Illinois, at the postal address provided. Thank you.