Can you please help me identity these symbols from a vintage (1960) diagram? The capacitors units are noted with "KP", sometimes just "K". What is the rectangle crossed with an arrow? It looks like a potentiometer without the tap connected.

1.what does kp means? pico farad?

Capacitor with "680 kp"

2. what is this symbol? 5/6?

Capacitor with the broad terminal partially clamping the short one; unit "5/6"

3. 47K farad?

Capacitor with "47 K"

4. 22k resistor or diode or bias pot?

Resistor or pot or even a diode?

The full circuit: Full circuit (source)

  • 1
    \$\begingroup\$ 47K farad? ... no. :) \$\endgroup\$
    – pipe
    Oct 2, 2016 at 18:21
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    \$\begingroup\$ 680 kilo-pico farads? \$\endgroup\$
    – Armandas
    Oct 2, 2016 at 18:25
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    \$\begingroup\$ Likely 47000pf = 47nf and 680 nf. The arrows indicate potentiometers or variable resistors (use a pot, connect the wiper to one end). The other one looks like an electrolytic capacitor but "5/6" makes no sense as a value - is it perhaps the 5th section of a 6-section capacitor? (Packing several high voltage caps into one can used to be common, in the pre-transistor days). The full circuit may give enough context for a better guess. \$\endgroup\$
    – user16324
    Oct 2, 2016 at 18:26
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    \$\begingroup\$ Compare the 5uF/6Vdc at the input to the 5uF/12Vdc at the output. The voltage requirement at the output collector is somewhat higher than at the input... \$\endgroup\$
    – Maxjoha
    Oct 2, 2016 at 23:12
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    \$\begingroup\$ Seeing the circuit, yes the electrolytics are 5uF/6V and 12V, from the days when 12V electrolytics were larger and more expensive than 6V ones. As for the shape? The negative terminal is usually the outer can. \$\endgroup\$
    – user16324
    Oct 3, 2016 at 12:15

1 Answer 1

  1. capacitor 680 kilo-pico-Farad (kpF) same as 680nF
  2. Capacitor 5uF 6Volt.
  3. 100k ohm potentiometer
  4. 22k ohm trimer potentiometer

All capacitors marked k are in kpF which is the same as nF The line inside the resistors means that those are thin film resistors either carbon or metal.

This is a NPN BJT based circuit, GND is connected to the positive of the battery and negative terminal is marked + but GND should be negative despite teh battery symbol being wrong.

  • 1
    \$\begingroup\$ 1) Electrolytic cap: I agree about the value of 5uF / 6V but the small terminal should be positive; the large terminal should be negative. 2) Transistors appear to be NPN. Google also thinks that the transistors are NPN. 3) There is a really good chance that the capacitor marked "680kp" is 680nF Polystyrene (low leakage and very stable). – Dwayne Reid 7 hours ago \$\endgroup\$ Mar 9, 2017 at 14:51
  • \$\begingroup\$ Yes you are right, I have updated the answer. \$\endgroup\$
    – 555
    Mar 9, 2017 at 14:57
  • \$\begingroup\$ I think the + sign is on the right side but the battery is upside down. \$\endgroup\$
    – Oskar Skog
    Mar 9, 2017 at 15:39
  • \$\begingroup\$ That is correct, the thin and long line in the battery symbol is the plus terminal, but the symbol is upside down \$\endgroup\$
    – 555
    Mar 10, 2017 at 22:17

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