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Old 01-14-2020, 01:49 PM   #121
R_J
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Default Re: Help with dead Commodore 1802

At filter cap C803 there is no AC voltage. This is correct! IT IS DC VOLTAGE!!!!
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Old 01-15-2020, 02:17 PM   #122
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Default Re: Help with dead Commodore 1802

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At filter cap C803 there is no AC voltage. This is correct! IT IS DC VOLTAGE!!!!
Yes thats right. No voltage at filter cap. I am right measuring accros the 2 cap contacs (+and -).
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Old 01-15-2020, 02:39 PM   #123
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Default Re: Help with dead Commodore 1802

What do you have in place of the resistor? if there is nothing there, You will not get any voltage across the capacitor because you are not getting any AC to the diodes.

Last edited by R_J; 01-15-2020 at 02:48 PM..
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Old 01-17-2020, 02:12 PM   #124
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Default Re: Help with dead Commodore 1802

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What do you have in place of the resistor? if there is nothing there, You will not get any voltage across the capacitor because you are not getting any AC to the diodes.
I put this bulb ain place of the resistor maybe i need a bigger bulb? It measures 72.5 ohms.
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Old 01-17-2020, 09:30 PM   #125
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Default Re: Help with dead Commodore 1802

strange, you should see some voltage and some life from the lamp.
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Old Yesterday, 11:33 AM   #126
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Default Re: Help with dead Commodore 1802

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strange, you should see some voltage and some life from the lamp.
Well I just wired one of those ever ready bulbs to 240v mains and it doesnt light up. They all seem to be the same. They are nor open circuit and show a resistance but dont iluminate with 240v ac. I think these bulbs are what are fitted into ovens etc but surely they should light up. I will go andf buy some more of the bigger ceiling type bulbs tomorrow and have another go. No wonder we havent been getting anywhere.
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Old Yesterday, 02:27 PM   #127
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Default Re: Help with dead Commodore 1802

it's really strange that you see a resistance but no life - be interesting to do an autopsy and cut the metal cap open!
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Old Yesterday, 05:55 PM   #128
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Default Re: Help with dead Commodore 1802

I just checked a couple incandescent lamps, these are 120vac 60watt = 16Ω. (Christmas light) 120vac 7 watt = 189Ω, Appliance lamp 120vac 40watt = 27Ω

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