Plastimo Conquest compass light

Minchsailor

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Plastimo Contest compass light

Plastimo say that the light bulbs have to be replaced on a like-for-like basis. If the compass originally had an incandescent bulb fitted, it should not be replaced with an LED.

Why?.

Anybody replaced with an LED? Compass dates from 1990.
 
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Re: Plastimo Contest compass light

The original bulbs are tiny incandescents that come with a twisted-wire lead to reduce as far as possible compass errors from the current flowing through the wires creating magnetic fields.

As the magnetic field effect is proportional to DC current, and an LED should be a lot lower current, I really can't see any reason not to wire a small 12v LED into the same twisted wires - keep the twist going right up to the compass body.

Obviously test before and after for compass errors.
 
I did this some time ago with my Plastimo Olympic 135compass, which had 3 bulbs in it. I did as John said in post #3 regarding the twisted wires and it has not been a problem. I bought the LEDs from Ebay, i used red "grain of rice" LEDs as used by model makers etc.
 
£6.25 + shipping !!! They are taking the proverbial. Halfords do wee bulbs (1.2W @80p) if you want to stay incandescent - add a resistor if it is too bright.

It was a lot - then we had to get it flown out to Sardinia but fortunately by a guest who was joining us. Frankly though with a lot of night sailing to do it was trivial compared to all the other bits and bobs we'd spent almost a thousand on. Sometimes expediency rules the wallet, possibly too often for me.
 
£6.25 + shipping !!! They are taking the proverbial. Halfords do wee bulbs (1.2W @80p) if you want to stay incandescent - add a resistor if it is too bright.

I doubt that any normal car bulb will fit in the Contest compass - the original bulb is a "large grain of rice" sized item with soldered on twisted pair wires.
 
I doubt that any normal car bulb will fit in the Contest compass - the original bulb is a "large grain of rice" sized item with soldered on twisted pair wires.

May I assuage your doubts. A capless 1.2W instrument bulb, needs wires soldered to its tails + a bit of heatshrink, fits nae bother at all and others have used LEDs. I don't think it's parsimony, just a concept of value.
 
May I assuage your doubts. A capless 1.2W instrument bulb, needs wires soldered to its tails + a bit of heatshrink, fits nae bother at all and others have used LEDs. I don't think it's parsimony, just a concept of value.

The capless instrument bulbs are physically much larger than the original bulbs. The grain of rice bulbs i mentioned previously are the same size and cost pence.
 
Re: Plastimo Contest compass light

I replaced my bulb while cruising this summer. I was surprised the chandlery had the right bulb with twisted wires etc in stock in a small plastic bag, in fact he had quite a few. The cost was so low it really wasn't worth messing about trying to find alternatives.
 
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