User manual HARBACH ELECTRONICS SK-201

[. . . ] SK-201 "SOFT KEY" INSTALLATION INSTRUCTIONS PART S SUPPLIED WITH T HIS KIT : (1) SK-201 "S oft Key" Circuit Board Assembly (1) Nylon Threaded Spacer (2) 6-32 x ¼" Screws (1) 2-Lug Terminal Strip (1) #6 Lock W asher To start the installation, read these instructions very carefully. Unplug the amplifier and remove any input, output and control ca bles that may be connec ted to the back of the amplifier. Remove the chassis from the case and remove the perforated sheet metal RF shield from the top of the chassis. [. . . ] Put on a lock washer and attach the nylon spacer onto the screw (on the underside of the chassis and tighten. Inside the tube compartment, locate the screw that fastens the RF shield to the chassis and secures terminal strip "Q" to the underside of the chassis. Terminal strip "Q" is a 5-lug strip mounted at a right angle to the re ar of the chassis. Loosen this screw and remove the nut while keeping the screw through the chassis. Place the hold down lug of the supplied 2-lug term inal strip over the end of the 6-32 screw (the one you just rem oved the nut from). It may require some a djustment of the wiring harness to m ake room for the strip. The strip should be oriented approximately parallel w ith the existing terminal strip "Q". Reinstall the 6-32 nut onto the screw and tighten. Now turn the am plifier over (bottom up). Locate the 33 1W resis tor going from the antenna relay jack on the rear panel to a solder lug at the end of the primary voltage selection strip. Unsolder the res istor from the jack and move the end so that it goes through the insulated terminal on the 2-lug terminal strip you just installed. Leave the 0. 02µF disc capacitor connected to the antenna relay jack. Install the SK-201 circuit board on the nylon spa cer w ith a 6-3 2 x ¼" screw. Orient the circuit board with the long side parallel with the rear of the chassis and the TO-220 transistor away from the rear of the chassis. () () () () () () () 1 () Connect the BLACK wire from the SK-201 circuit board to the grounded lug of the 2-lug term inal strip (installed earlier) and solder. [. . . ] Solder the GREEN wire to one of the lugs where the filament choke is attached. Reinstall the tubes and the perforated sheet metal RF shield on the top of the chassis and put the chassis back into the case. () () () () () () This completes the installation of the S K-201 "Soft Key" module. You may not SEE any difference in the operation of your exciter or amplifier, but you will know that you have reduced the stress on the exciter's keying relay by many orders of magnitude. 2 SK-201 "SOFT KEY" MODULE PARTS LIST R1 R2 R3 C1 D1 D2 D3 IC1 100K ½W 5% 10K ¼W 5% 2K ¼W 5% 100µF 10VDC 1N4005 (1A 600 PIV) 1N5817 SC HOT TKY (1A 20V) 1N60 GERMANIUM 4N33 OPT OCO UPLER HARBACH ELECTRONICS Jeff Weinberg ­ W8CQ 468 County Road 620 Polk, OH 44866-9711 (419) 945-2359 http://www. harbachelectronics. com info@harbachelectronics. com 3 [. . . ]