DC electrical System?

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paul213
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why do you need to isolate the lighting coils from the frame? I was looking at an original 6v battery wiring diag and it uses both ac brown feed to h/lght rear light, and dc horn brake light and parking light both using the the frame for the -ve/return feed.
I want to try to understand because I want to restore a gp but fitting electonic ignition instead of points with the components hidden inside the original rectifier/reg cases.

Paul
firekdp
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Paul, there are no problems when using a common earth for AC and DC on the original 6v system as they were two seperate supplies. The problem only arises when using a bridge rectifier, because if both the AC input and the DC output both connect to earth then one of the bridge diodes is effectively shorted out. This means that one half pulse is lost through this short and only leaves the other as a half wave output.
paul213
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I think Ive got the gist of that .

many thanks Paul
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CANbus
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IMO, after the hydraulic front disc brake this has to be next best modification I have done, the lights are bright as.
11111111 = 0xFF
J1MS
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firekdp wrote:Paul, there are no problems when using a common earth for AC and DC on the original 6v system as they were two seperate supplies. The problem only arises when using a bridge rectifier, because if both the AC input and the DC output both connect to earth then one of the bridge diodes is effectively shorted out. This means that one half pulse is lost through this short and only leaves the other as a half wave output.
Thats how I run two of mine. Using the rectifier as it really wasnt meant to be, this giving half wave rectification with a common earth. Simple, but possibly a little inferior.
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Spud
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Where can i get one of the podtronic units from?
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soulsurfer
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Spud wrote:Where can i get one of the podtronic units from?
Contact this guy for the Wassell unit, the same but half the price ;)
http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... K:MEWAX:IT
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Spud
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cheers soulsurfer
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Spud
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What is the general view, battery or not!
I am not going to run any extra lights, just want to have a horn that can be heard & lights to see.
+ a fuel gauge.
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soulsurfer
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I use one with a battery and one without, try it and see but may be sensible to use one with a fuel gauge.
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