Electronic Components On-hand

These are some of the components available for testing.

Variable Capacitors

Typical
TypeNominal (pF)Drive MinMax
Air 365Direct
Air 3818:1 Planetary 14 400
Air 320/3806:1 Vernier
Air 320/14.7/380/14.73:1 Vernier 12/9/12/9345/25/405/25
Air 480/5056:1 Vernier 8/8 520/500
Plastic 60/160Direct 84 184
Plastic 266/266Direct
Piston, Hi-Q 1-25Direct
Compression 6-50Direct

Crystal Radio Inductors

Inductance needed for capacitor values.1)

C=381+20=401 pF, f=520 kHz = 3.267e6 rad/secomega =1/{sqrt{L C}} right L=1/{C omega^2}=1/{401*10^{-12} *3.267^2*10^{12}}=234 mu H

CmaxCstrayL(520 kHz)C(1710 kHz)
(pF) (pF) (µH) (pF)
365 20 243 36
410 20 218 40
380/320 20/20 234/276 40/20

Torroid Winding

Core Winding Inductance (µH)
ALDone Length LayersTurns* Calculated Measured
2xFT23-43 2×158±20% 15”? 2 28 248
f8FT23-43 2×158±20% 23”? 2 2×28 248
FT37-43 350±20% 17” 1 26 237
FT50-43 440±20% 19” 1 23 233
FT50-61 69±20% 42” 1 58 232
T130-2 11±20% 214” 1 145 231
T200-2 12±20% 266” 1 138 229

Giant Ferrite Bead Information

  • It takes about 20' of 30 gage wire to wind a giant bead fully (estimated 92 turns) for about 20 mH (measured 19.4 mH). [2007-11-13]
  • About 2.43”/turn
  • uH={A_L *Turns^2}/1000 right A_L={1000 L}/{Turns^2}={1000*113}/{7^2}=AL≈2300

Big Ferrite Torus

  • uH={A_L *Turns^2}/1000 right A_L={1000 L}/{Turns^2}={1000*62}/{11^2}=AL≈512
  • Turns=sqrt{{1000 L}/{A_L}} = sqrt{{1000*184}/512}approx19 turns

Other Coils

  • The cigar box radio coil is about 23 turns of #26 (or #24) around a 5½” x 9” x 2½” box, around 80' of wire.
  • 6' of 16-conductor ribbon cable makes a quick and dirty coil.

Joule Thief Transformers

Coils to Wind Twice with 30-gauge Wire

Core Winding Inductance (µH)
ALDone Length LayersTurns* Calculated Measured
FT23-43 158±20% 10” 1 14 31 46
FT23-43 158±20% 2 28 124 241
2xFT23-43 2×158±20% 1 14 62 93
2xFT23-43 2×158±20% 2 28 248
f8FT23-43 2×158±20% 1 2×14 62 93
f8FT23-43 2×158±20% 2 2×28 248
FT37-43 350±20% 30” 1 20 140 126
FT37-43 350±20% 60” 2 42 617
FT37-61 55±20% 31” 1 21 24 18
FT37-61 55±20% 62” 2 42 97
T37-2 4±5% 31” 1 25 2.5 UR
T37-2 4±5% 62” 2 50 10
T37-6 3±5% 31” 1 25 1.9 UR
T37-6 3±5% 62” 2 50 7.5
FT50-43 440±20% 50” 1 36 570
FT50-43 440±20% 112” 2 72 2281
FT50-43 440±20% 40” 1 28 345 367
FT50-43 440±20% 36” 1 24 253 277
FT50-43 440±20% 30” 1 20 176 190
FT50-61 69±20% 56” 1 36 89 69
FT50-61 69±20% 112” 2 72 358
T50-26 56” 1 36 41
T50-26 20” 1 21 14 11
T50-1 10±10% 56” 1 36 13 8
T50-1 10±10% 112” >2 72 51 49
T50-2 4.9±5% 56” 1 36 6.4
T50-2 4.9±5% 112” 2 72 21
T50-6 4±5% 56” 1 36 5.2
T50-6 4±5% 112” 2 72 16
  • μH = (AL*Turns²)/1000
  • * Italics indicate a full winding.
  • Not tested. The inductance is not appropriate for a joule thief.
  • Tested in a joule thief circuit.
  • 2x indicates two cores stacked and wound together.
  • f8 indicates a figure-eight winding of two cores side-by-side.
  • UR indicates inductance too low for my cheap multimeter to register.
Color u Frequncy (MHz)
-43 Shiny Black 850 (0.5-30)
-61 Dull Dark Gray 125 0.2-15
-26 Yellow/White
-3 Gray 0.050-0.5
-1 Blue/Clear 20 0.5-5, 0.15-3
-2 Red/Clear 10 2-30, 0.25-10
-6 Yellow/Clear 8.5 10-50, 3-40

Data adapted from Maximum Turns, Toroid Windings for QRP projects, Mike Czuhajewski's Toroid Charts, and Ian Purdie VK2TIP's "Toroids" page.

Diodes

Part TypeIF(AV)VRRated VF*VF@20mA,25ºCMeasured VFCT
(A) (V) (V) (V) (V) (pF)
1N5817 Schottky 1 20 0.45 0.23 0.165 125
1N5819 Schottky 1 40 0.45 0.23 0.205 110
21DQ06 Schottky 2 60 0.55 <0.32 0.298 120
MBR1100 Schottky 1 100 0.68 <0.42 0.299 35
BAT46 Schottky 0.15 100 0.80 0.51 0.254 6-10
1N34A? Schottky 0.307
1N34A Ge 65 >1.00 >1.00 0.8
1N60 Ge
1N60-odd Ge
1N60P Schottky 0.5 45 0.84 0.34 0.279 2-6
1N198 Ge 0.5 100 1.00 >1.00 0.278 low‡
1N277
1N277B
“Unknown” Ge 0.364
“Mystery” Ge 0.293
  • *Usually @IF(AV), TJ=125ºC
  • †Measured with cheap multimeter, probably at about 1.25 mA
  • ‡Observed to be similar to 1N34A.

Transistors

Part PolarityMaterialVFBEVIC,maxhFEfTUse CoilPackage
V V mA MHz µH
ГТ402Б PNPGe 0.201 25 500 60-150 1 Russian Package bip-51
ГТ404Б NPNGe 0.168 25 500 60-150 1 Russian Package bip-51
гт4125 PNPGe 0.260 24 500 ≥70 2300-600
2N1017 PNPGe 0.226 ?10 400 20-30 2020-400
1T321E PNPGe 0.128 40 200 80-200 60 Russian Package bip-19
Кт321Б PNPSi 0.646 50 200 40-120 60 Russian Package bip-19
SFT131 PNPGe 0.166 24 500 ≥70 2 TO-5var
MP26A PNPGe 0.212 70 400 20-40 0.2 TO-9

”…the emitter-base junction possesses a slightly greater forward voltage drop than the collector-base junction.”–Lessons In Electric Circuits -- Volume III, Chapter 4


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