Harbach Electronics FB-220 User Manual

FB-220 FILTER CAPACITOR BLOCK INSTALLATION INSTRUCTIONS

PARTS S UPPLIED WIT H THIS KIT:

(1) FB -220 Filter Capa cito r Block Ass embly

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 ca se in place. Lift the case up and remove it from the amplifier. Place the amplifier on the
bench with the front panel facing you. You are now ready to proceed with the installation.

( ) Remove the 15 sheet metal screws that hold the perforated cover in place and remove this

along with the to p rear plate cover.

( ) Remove the top rear 6-32 screw, nut and washer holding the right side panel in place along

with the 4 sheet metal screws that attach the right side panel to the chassis.

( ) Remove the top front Phillips-head screw on the right side of the front panel. This will

release the right side pan el for removal.

( ) Tip the amplifier onto its left side.

( ) Unsolder the 3 wires attached to the old capacitor bank. There is a BLACK wire from the

rectifier board, a BLUE wire also from the rectifier board and a RED & YELLOW wire from

the HV transformer.

( ) Remove the (4) 6-32 nuts and washers securing the capacitor bank bracket. N ow lift the

bracket up abou t ½”.

( ) Remove the 8 capacitors and the nylon spacers. This task can be made easier by cutting

som e of the w ires between th e capac itors (they are no longe r needed).

( ) Slip the replacement capacitor bank into the cavity vacated by the old capacitor bank with

the solder lugs toward the front panel. Make sure that you fully slide the block to the

rear of the cavity. Now, slide the assembly approximately 1/16” out of the cavity.

( ) Press down on the capacitor bank bracket and reinstall the (4) 6-32 nuts and washers.

Depending on the tolerances of the bracket, you may have to leave off the washers.

Tighten the nuts securel y.

( ) Solder the 3 wires you removed earlier; The BLUE to the bottom solder lug, the RED &

YELL OW to the middle lug and the BLACK to the top lug.

( ) Place the right side panel in position and secure with the 4 sheet metal screws removed

earlier.

( ) Reinstall the top front Phillips-head screw on the right side of the front panel and tighten.

( ) Reinstall the 6-32 screw, nut and washer in t he top rear of the back pan el.

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( ) Replace the perforated cover and top rear plate cover. Reinstall the 15 sheet metal screws

holding these pieces in place. DO NOT over tighten these screws, as it is fairly easy to

strip the screw threads in the aluminum underneath.

( ) Use the book to hold the amplifier while you reinstall the case an d feet.

This com ple tes the installation of the FB-220 filter capacitor block. It will provide you with a
better power supply that provides the necessary B+ filterin g and reg ulation. Your am plifier shou ld
not experience any filtering problems in the future.

HARBACH ELECTRONICS

Jeff Weinberg – W8CQ

468 County Road 620

Polk, OH 44866-9711

[phone]

htt p://www.h arbachelectronics.com

info@harbachelect roni cs. com

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