User Guide

SS-221 “SOFT START” INSTALLATION INSTRUCTIONS

PARTS SUPPLIED WITH THIS KIT:

(1) SS-221 “Soft Start” Circuit Board Assembly

(1) Full-Wave Bridge Rectifier (1A 400 PIV)

(1) #8 Bent Solder Lug

(2) 200V ZNR Transient Suppressors

(1) 390V ZNR Transient Suppressor

(2) 1N4005 Diodes (1A 600 PIV)

To start the installation, read these instructions very carefully. Now unplug the amplifier

and remove any input, output and control cables that may be connected to the back of the

amplifier. Place the amplifier on a book, front panel up, and remove the bottom screws holding the

feet and case in place. Lift the case up and remove it from the amplifier. Place the amplifier

upside down on the bench with the front panel facing you. Place the SS-221 module in the open

space on the chassis over the capacitor bank with the attached large black leads coming out

toward the back of the chassis. You are now ready to proceed with the installation.

( ) Cut the 2 cable ties on the power lead wiring that are nearest the back panel.

( ) Locate the large black wire coming from the right hand terminal of the lower circuit breaker.

Unsolder this wire and clean the hole in the terminal of the breaker.

( ) Cut ½” off of the end of this wire and strip about ¼” of insulation from the end of the wire.

From the component side of the SS-221 circuit board, pass this wire through hole “C” and

solder.

( ) Solder the wire coming from hole “A” in the SS-221 circuit board to the circuit breaker

terminal just vacated, trimming as necessary. This is easiest to do by first tinning the end

of this wire.

( ) In a like manner, remove the large black wire from the right hand terminal of the upper

circuit breaker. Prepare the terminal and wire as previously described.

( ) Pass this wire through hole “D” on the SS-221 circuit board and solder.

( ) Solder the wire coming from hole “B” of the SS-221 circuit board to the circuit breaker

terminal just vacated, trimming as necessary. This is easiest to do by first tinning the end

of this wire.

( ) Locate terminal strip “BT”. It has 2 resistors, a 20µF capacitor and a diode connected to it.

It is located on the left side of the chassis, slightly forward of middle. Remove the diode.

Remove the red transformer wire connected to the center ground lug. Clean out the ground

lug and the lug that has the “+” terminal of the capacitor soldered to it.

( ) Find the small bridge rectifier supplied with the kit. Note that the (+) lead is slightly longer

than the rest. This is the plus (“+”) lead and is marked on the top of the bridge rectifier.

With the rectifier on the right side of the terminal strip (wires up), put the (+) through the

most forward terminal (lug) on the strip (the one with the “+” lead of the capacitor going to

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SS-221 “SOFT START” INSTALLATION INSTRUCTIONS PART S SUPPLIED WITH T HIS KIT : (1) SS-221 “S oft Start” Circuit Board Assembly (1) Full-W ave Bridge Rectifier (1A 400 PIV) (1) #8 Bent Solder Lug (2) 200V ZNR Transient Suppressors (1) 390V ZNR Transient Suppressor (2) 1N4005 Diodes (1A 600 PIV) To start the installation, read these instructions very carefully. Now unplug the amplifier and remove any input, output and control cables that may be connected to the back of the am plifier.
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it). Put the red lead from the SS-221 module through the same terminal lug, trimming as necessary. Solder 5 wires at this lug. () Put the (-) lead of the bridge rectifier that is opposite of the (+) lead through the cente r (ground) lug of the term inal strip. Put the black lead from the SS-221 module through the same terminal lug, trimm ing as necessary. Solder 3 wires at this lug.
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This completes the installation of the SS-221 “So ft Sta rt” module. Before putting the case back onto the chassis, it would be w ise to check the operation. NOTE: MAKE SURE THE "SAFTY BRASS SPRING INT ERLO CK" IS NOT GROUNDED BEFORE PLUGING INTO AN AC OUTLET. FAILURE TO DO THIS WILL SHORT CIRCUIT THE HIGH VOLTAGE SUPPLY TO GROUND AND DAMMAGE WILL RESULT IF POWER IS APPLIED! To do this, right the am plifier and plug it in and place the multi-meter switch to the “HV” position.