PARTS LIST FOR HOMEBREW POWER SUPPLY FOR ATLAS 210X TRANCIEVER
BY: RICK MCKEE, KC8AON

25 AMP, 50V PIV FULL WAVE BRIDGE RECTIFIER - RADIO SHACK # 276-1185  $2.99

LM317T ADJ VOLTAGE REGULATOR - RADIO SHACK # #276-1778 $1.99 (USE GOOD HEAT SINK)

1N4002 (RS DOESN'T STOCK, USE 1N4003) RS #276-1102 - S FOR $.59

4700uF 35V ELECTROLYTICS (NEED 8) RS #272-1022 #3.59 EACH (HAD MINE IN JUNK BOX)

2N3055 PASS TRANSISTOR, RS #276-2041 $1.99 (USE VERY LAGRE HEAT SINK AND INSULATE TRANSISTOR 
                                           FROM IT)  I ALSO USED A 24V COMPUTER FAN BLOWING ON
                                           MY HEATSINK FOR EXTRA COOLING.

.1uF DISK CAP 50V - RS #272-135 $.89

1uF 25V ELECTROLYTIC - RS DOESN'T STOCK, MAY FIND ONE IN THEIR 20 PACK - #272-802 - $2.99, 
                       MINE WAS IN THE JUNK BOX.

220 OHM 1/2W RESISTOR - RS #271-1111 5 FOR $.79

4.7K OHM TRIMPOT - RS #271-281 $.79 - USED TO ADJUST LO CURRENT SIDE TO 13.8 VOLTS OUT.

MISC:  FOUND IN JUNK BOX, HAMFESTS, OLD RECYCLED GEAR, OTHER HAMS, FLEA MARKETS !

TRANSFORMER:  24 VOLT CENTER TAPPED SECONDARY CAPABLE OF AT LEAST 8 - 10 AMPS CONTINUOUS.
              MORE IS BETTER !  MINE WILL HANDLE ABOUT 15 AMPS CONTINUOUS.

SPST TOGGLE SWITCH, BINDING POSTS, FUSES AND HOLDERS, CABINET, HEATSINKS, POWER CORDS ETC ETC

NOTE:  THIS CIRCUIT IS SIMILAR TO THE SUPPLY IN THE CONSOLE FOR THE ATLAS 210X, EXCEPT IT USES
       AN LM317T ADJUSTABLE VOLTAGE REGULATOR INSTEAD OF A ZENER REFEERENCE DIODE AND PASS 
       TRANSISTOR.  I ORIGINALLY THOUGHT THE LM317T WOULD BE ENOUGH BY ITSELF SINCE IT HANDLES
       1.5 AMPS, BUT I DIDN'T REALIZE THAT THE LOW CURRENT SIDE PULLED MORE THAN THAT DURING
       TRANSMIT. WITHOUT THE 3055 THE 317 WOULD LOADUP AND SHUT DOWN DURING TRANSMIT, SO I ADDED
       THE 2N3055 PASS TRANSISTOR AS AN EMITTER FOLLOWER TO UP THE CURRENT HANDLING CAPACITY 
       OF THE LM317T. WITH THE 317 SET TO 13.8 VOLTS OUTPUT, THE REGULATION DROPS TO 13.6 VOLTS
       ON TRANSMIT WHICH ISN'T ENOUGH TO WORRY ABOUT. MAKE SURE AND USE HEATSINKS ON THE 
       REGULATOR AND PASS TRANSISTOR. I BUILT MY REGULATOR UP ON A SEPERATE CIRCUIT BOARD, SO THE
       HEATSINK FOR THE 317 CAN BE BOLTED DIRECTLY TO IT, BUT BE SURE AND INSULATE THE 2N3055
       FROM IT'S HEATSINK IF THE HEATSINK IS GROUNDED TO THE CABINET. OR YOU CAN SIMPLY INSULATE 
       HEATSINK FROM THE CABINET AND BOLT THE 3055 DIRECT TO IT. MY POWER SUPPLY ALLOWS THE 210X
       TO TRANSMIT WITH FULL OUTPUT WITH NO OVERHEATING PROBLEMS, SO BUILD ON UP AND ENJOY !

BEST 73,
RICK MCKEE, KC8AON
WILLOW WOOD, OHIO