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I'm trying to repair an old record turntable (Dual CS 5000).

From what I can tell the problem is a component that looks like a standard carbon film resistor, but for which I cannot find a colour code lookup for.

The colour bands are: Brown/Grey/Gold/Gold/Yellow.

It seems it's the gold band in the middle that isn't "standard". Both gold bands look exactly the same: sparkly, unlike the other colours on the component (see photo). The only other distinguishing feature of the component is that the "output" end is sheathed in green plastic. On the circuit board the "name" given to the component is "RP07". The symbol on the board is a circle with a half/radius line through it from the centre to the edge.

Other resistors seem to be labelled "RRxx", have recognisable colour codes, and show the corresponding ohms. So I'm beginning to doubt this is a resistor, or at least think it's something a bit exotic.

Using a simple multimeter I get "1" on all of the ohm settings.

If anyone can identify this component for me I'd be extremely grateful.

enter image description here

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  • \$\begingroup\$ Can you give us pictures of the board it came from, and schematics? \$\endgroup\$
    – Hearth
    Nov 29, 2022 at 16:05
  • \$\begingroup\$ If you interpret that as a 4-band resistance code + a temp-co band, then it would be 1.8 ohms, 5%, 25ppm. But I don't think that would be a "standard" interpretation. \$\endgroup\$
    – brhans
    Nov 29, 2022 at 16:11
  • \$\begingroup\$ Perhaps an inductor, 1.8 µH? \$\endgroup\$
    – KristoferA
    Nov 29, 2022 at 16:44
  • \$\begingroup\$ Thanks to other posters for their interest, and suggestions. Very much appreciated. \$\endgroup\$
    – Richard
    Nov 29, 2022 at 18:23

1 Answer 1

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The service manual is available here.

The symbol on the circuit board appears to represent a resistor that is placed standing up:

enter image description here

The value for RP07 is given in the schematic diagram:

enter image description here

That's 1R(squiggle) where the squiggle is probably an 8.

You would read the resistor in the opposite direction from your picture:

enter image description here

That's brown, gray, gold, gold, yellow. Brown is 1, gray is 8.

Going by the Wikipedia color code chart, I'd say that the correct interpretation is:

Color Value
Brown 1
Gray 8
Gold X0.1
Gold Tolerance 5%
Yellow Temperature coefficient 25 ppm/K

That's a 1.8 ohm resistor with 5% tolerance and 25 ppm per degree Kelvin. From the size, I'd say it is a 1/4 watt part.

If your meter is showing "1" in the left most position, then that means the resistor is open circuit. I see what looks like a burned spot in picture of the resistor - it also appears to have cracked. It is burned out.

Purchase a replacement part, then try to find out why the resistor burned out before replacing it.

There is another resistor marked "RP" - that's RP08. All the components appear to have two letter designators. All the ones that have "P" for the second letter seem to be part of the power supply.

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    \$\begingroup\$ Looks right on value and tolerance, but I kinda doubt the 25ppm on a junky 5% resistor. Maybe it's a non-standard indication of power rating (yellow = 1/4W)? \$\endgroup\$
    – Spehro Pefhany
    Nov 29, 2022 at 17:13
  • \$\begingroup\$ Wow! I've only been out a few hours and in that time you've found a circuit diagram, and the colour codes. Thank you very much for providing such a comprehensive answer. I have already changed the transformer on the turntable as it was knackered, and I'm guessing however that happened might be related to this resistor blowing. Unfortunately, my Dad (whose turntable it was) is now 103 and unable to remember how it became defunct. If I can get it going - thanks to your help - he'll be overjoyed. \$\endgroup\$
    – Richard
    Nov 29, 2022 at 18:22

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