These modifications apply to PK-232s with serial numbers under 1000.

Four simple hardware modifications improve the PK-232's performance.

1.  Change C54 from:  0.1 mfd 10% mylar   (increase low-frequency  rolloff)
                 to: 0.01 mfd 10% mylar

2.  Change U16 from:  74LS04   (do this only if bbRAM does NOT hold memory)
                 to:  74HC14
3.  Change R35 from:  20K 5%   (improve VHF/Morse sensitivity)
                 to:  39K 5%
4.  Add:  0.047mfd mylar 10% in series with R79 (same as above)

GW1NGL NA7KR Kevin Roberts Ham Radio

Page last updated on 09/10/2012 by Kevin Roberts NA7KR a colection of Ham Radio and Electronic Information