Mini bulb

Discussion in 'Tech talk' started by Mark withey, Nov 16, 2025.

  1. Mark withey

    Mark withey New Member

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    What’s everyone’s go to replacement for these little darlings …the bulb that is , getting lots of different opinions
     

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  2. Hyperscope

    Hyperscope Well-Known Member S2G Supporter

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    E-bay to find incandescent grain of wheat bulbs. Or LED ones that will work with the supplied voltage.
     
  3. Mark withey

    Mark withey New Member

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  4. radiorich

    radiorich Active Member

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  5. Black Fingers

    Black Fingers Active Member

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    Before ordering check in the service manaul the voltage and what milli amps it uses otherwise you get one bright and one dim one...or change both bulbs at the same time, if one goes the other will follow
     
  6. Longman

    Longman Well-Known Member S2G Supporter

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    I used a white LED to replace the burnt out power bulb in my Weltron 2001. I did find that, as supplied as a 12V unit on eBay the LED was far too bright due to a low value resistor under sleeving just behind the LED. I don't recall exact values but I ended up fitted a resistor of about ten times the value.
     
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  7. Michiel

    Michiel Well-Known Member S2G Supporter

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    To calculate the resistance of the resistor in series with the LED, you can use this formula:

    R[led]=(V[source]-V[led])/I[led]

    In which:

    R[led] = resistance for the needed resistor in series
    V[source] = voltage of the source
    V[led] = operating voltage of the LED, typical 2V for a red LED, 3V for a white LED.
    I[led] = current for the LED, typical 0.02A
     
  8. AE_Stereo

    AE_Stereo Active Member S2G Supporter

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    Usually such bulbs will be having the same working voltage as that of the unit.

    But, I have seen some units having AC power to the bulbs rather than DC.
    You need to confirm if the bulb is getting DC or AC voltage. (Of course, LEDs will work on AC, but it will be loaded on the reverse cycle, which is not good I think.)

    If it is AC, better to use an AC to DC rectifier along with LED. You will need to add a Diode bridge circuit to the LED.

    There are prewired LEDs with fitted resistor available on ebay or aliexpress working on 12V, 15V DC etc.
     
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  9. Longman

    Longman Well-Known Member S2G Supporter

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    That is what I bought. My point was that they seem to be optimised as an extra-bright headlight for a model train rather than the subtle mood lighting required in HiFi,
     
  10. AE_Stereo

    AE_Stereo Active Member S2G Supporter

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    Brightness can be reduced by adding additional resistor.
     
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  11. Longman

    Longman Well-Known Member S2G Supporter

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    Or replacing the supplied resistor with a much higher value like I did.

    My original point was that the "12V" ones I bought weren't suitable for use as panel lights as supplied, being many many times brighter than a 12V grain of wheat bulb.
     
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