Signal Booster

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Correct cassette loading problems

The signal booster consists of one miniature audio transformer. The transformer is used as an interface between the computer and the cassette player.

Example:

               Signal
               Booster          recorder
                              +-------+
+----------+       v           |       |
|   load   | <    +--+   <in   |       |
|          |------|  |---------|  ear  |
+----------+ out  +--+         |       |
computer                       +-------+

The signal booster has the following advantages:

1. Isolates the computer from the cassette player which eliminates noise.
2. Increases the audio signal amplitude.
3. Cassette player volume setting can be adjusted to a lower level, thus improving the signal/noise ratio, this lower level setting decreases the inherit noise caused by high level of volume setting of volume control of most cassetter players.
4. Increased signal amplitude, allows for misalignment of the record/playback head, which causes low signal amplitude.
5. No power required.
6. LOW COST

SCHEMATIC: T1

        green          red
      +-------+ || +-------+
      |  ct   } || {  ct   |
 <----+  1KΩ  } || {  8Ω   +---->
J1 <----------+ || +-------------> J2
        blue           white

CONSTRUCTION

1. Drill two # .250 (1/4 inch) holes in a plastic pill bottle,one thru the cap, and the other thru the bottle bottom.

2. Solder transformer leads to jacks (J1) and (J2) as per schematic, then insert into plastic bottle.

NOTE: Don’t use a metal container, the metal prevents the proper isolation and grounding between the computer and the cassette player.

Parts list

1. T1-1K CT. to 8 ohms-Radio shack (273-1380)
2. J1 – J2 Radio shack (274-297)
3. Plastic pill bottle to fit transformer

When using signal booster use a lower volume setting for best results.