¢ ①②②②②②②②②②②②②②②②②②②②②②②②②②②❎¢ |1050 DISK DRIVE POWER PACK|¢ |>>>>>BY BRAD JAWORSKI<<<<<|¢ ⇧②②②②②②②②②②②②②②②②②②②②②②②②②②⇦¢ |DIAGRAM BY MATHEW BENNETT!|¢ ə②②②②②②②②②②②②②②②②②②②②②②②②②②⇨¢¢ חמקפנגרבקחנמ¢¢ The two main reasons for making this¢power pack are:¢1.The power pack will last much longer¢ than the origional because it is air¢ cooled.¢2.It is easily repairable without great¢ expense.¢¢ A slight drawback is a slight hum that¢the exposed transformer makes. This can¢be controlled further if thin rubber¢bushings are used between the¢transformer and the base. I did not use¢the rubber bushings and now do not even¢notice the hum.¢¢ The disk drive needs 9volts AC¢(alternating current) applied to it for¢power. This is done by using an 18 Volt¢AC transformer (easy to obtain) with a¢CT (center-tap). We use the center-tap¢to reduce the voltage by one-half to¢get the needed 9volts AC.¢¢ Do not worry that the 9volts AC is not¢regulated because the power pack is¢only stage one, of several stages, to¢supply power to the drive. The other¢stages are within the drive itself and¢the power is transformed into a well¢regulated +5 volts DC and +12 volts DC.¢(see power supply diagram)¢¢ ח∈≤⌠≥⌡π⌠Θ∩∈≤¢¢ 1) The first thing to do is to cut off¢ the wires (two) from the base of the¢ orginal old transformer. Make sure you¢ cut the wires off near the base. You¢ will need these wires for the project.¢¢ 2) To start simply anchor the trans---¢ former to the floor of the cabinet¢ near the vent holes. (rivets or nuts--¢ and bolts)If you want less transformer¢ hum, you can put rubber bushings¢ between the transformer and the floor.¢ (not need)¢¢ 3) Drill holes the required size for¢ strain reliefs and the fuse holder. 3¢ holes in all. (hardest part of the pro¢ ject)¢¢ 4) Mount the fuse holder (epoxy if----¢ necessary) and the power and supply¢ wires. Use the strain reliefs with the¢ wires to prevent short circuits.¢¢ 5) Attach all wires inside the cabinet¢ with wire connectors (wire nuts) as in¢ the diagram. Attach the 120volt AC¢ plug wires (two pronged) to one of the¢ 120volt wires (black) on the primary¢ side of the transformer and solder the¢ other wire to one of the fuse holder¢ terminals.¢¢ 6) Next connect the other 120volt AC¢ transformer wire to the other fuse¢ holder terminal. (both transformer ---¢ wires on the primary 120volt side are-¢ black) It does not matter which trans-¢ former wires you use on the 120volt AC¢ side.¢¢ 7) Next connect the two wires that go¢ to the disk drive. The black wire with¢ the white stripe goes to one of the¢ yellow wires(doesn't matter which one)¢ and the black goes to the black(center¢ tap)on the transformer 9volt secondary¢ side. (on the transformer, Yellow to--¢ Yellow will give you 18volts AC)Yellow¢ to Black (center-tap) will give you 9-¢ volts AC. Don't forget to put a wire¢ connector on the Yellow secondary wire¢ not being used. This prevents it from¢ shorting out on the cabinet.¢¢ 8)Install fuse and power pack is ready¢ to be used. One Amp Fuse is well below¢ the 2 Amp rating of the transformer.To¢ make a long story short, the trans----¢ former is working at less than half¢ its capacity and as a result will last¢ a long time.¢¢¢מנקד: A switch may be added if desired.¢ All my electronic hardware is on a¢ Voltage Spike Protected AC Power¢ Strip with one switch. It turns¢ all powered items off and on¢ making a switch unnecessary.¢¢ Each disk drive requires 1 18volt¢ AC transformer. Do not use the¢ other Yellow wire(the one not used¢ ) to power another disk drive. It¢ will not work.¢¢¢ סIJפקצáכחצק¢Radio Shack:¢ 1 273-1515 Transformer $8.99¢ 18volt CT¢¢ 1 270-1273 Fuses $ .79¢ Fast acting¢¢ 1 270-251 Metal Cabinet $5.99¢ 6x2 3/8x4¢¢ 1 64-3026 wire Connectors $1.29¢ 16 assorted¢¢ 1 278-1636 Strain Reliefs $ .69¢ Set of 6¢¢ 1 270-364 Fuse Holder $1.29¢ panel mount¢ (long type)¢ -----¢ TOTAL = $19.04¢ --------------------------------------¢¢ ⇩גחIJופIJל⑥¢¢ (VENTS ON SIDE CABINET)¢ ①②②②②②②②②②②②②②②②②②②②②②②②❎¢ | |¢ | |¢ ①②❎ |①❎¢ FUSE:①⇦|| ⇧②②②②②②②②②②②②②②②②②②②②②⇦|②¢
ə⇦||♪ ⇧②②②②②②②②②②②❎ ①②②②②②②②⇦|②¢ ə②⇨
(BLACK) | |BLACK |ə⇨¢ | ①②⑧②⑧②❎ |120V¢ | | PRI | | --¢TO: DISK | ①⑧②②②②②⑧❎ | AC¢
