Pocket Class A Headamp BOM
NHB Caps Version KA-Silmic v2 Dec 17, 2017
Label on Board Value Qnty Part No. Notes
R1 100k 2 0805 1/8W Metal Thick Film 1%
R2 47k 2 0805 1/8W Metal Thick Film 1%
R3 1k 2 0805 1/8W Metal Thick Film 1%
R4 33R, 47R, or 51R 2ea=6 0805 1/8W Metal Thick Film 1% (nominal is 33R, increase for higher bias)
R5 270R 2 0805 1/8W Metal Thick Film 1%
R6 47R 2 0805 1/8W Metal Thick Film 1%
R7(1-4) 470R 8 0805 1/8W Metal Thick Film 1%
RLED 12k 1 0805 1/8W Metal Thick Film 1%
RL 270R 2 0805 1/8W Metal Thick Film 1%
C1 10uF 35V 2 RFS-35V100ME3#5 Elna Silmic II radial 2.5mm (+ve faces JFET gate)
C2_1 2200uF 16V 2 UKA1C222MHD Nichicon KA radial, place Wima 2.2uF MKS bypass on same pins on SMT side
C2_1 (SMT side) 1uF 63V 2 MKS2C041001F00KSSD Wima MKS film radial 5mm
C2_2 n/a 2 n/a Not used to make space for sideways mounted 2200uF KA cap
C3 2200uF 16V 2 UVK1C222MPD Nichicon, use shrinktube on legs
C4 100nF 50V 2 08055C104KAT2A AVX Corp 0805 0.1uF 50V X7R MLCC
C5 100nF 50V 2 08055C104KAT2A AVX Corp 0805 0.1uF 50V X7R MLCC
Q1 BF862 2 BF862.215 N-junction JFET (NXP)
M1 ZVN4306 2 ZVN4306GTA  N-ch MOSFET (ZETEX/Diodes Inc)
Input 3.5mm stereo jack 1 35RAPC4BV4 Switchcraft
Output 3.5mm stereo jack 1 35RAPC4BV4 Switchcraft
Pot 10k linear w/ power 1 RK0971221Z05 Alps Rk09 with 6mm shaft with flat and on/off switch
LED 3mm 1 blue and white provided Any color, use shrink tube on legs and bend 90deg
BATT JST 4-pin 0.1in pitch 2
Battery leads 9v snap leads, 6in 2 236 Keystone
Vol Knob 6mm shaft with flat 1 Machined Aluminum, 12mm dia max
For more tips see GB thread on DIYAudio http://www.diyaudio.com/forums/group-buys/302859-xrk971-pocket-class-headamp-gb.html