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Author Topic: Capacitors - wrong orientation? (Read 1700 times)

Online gflorez

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Re: Capacitors - wrong orientation?
« Reply #45 on: 2020.October.12. 09:32:13 »
Remember its first name: Damp Proof Course.

The first phases of development were strictly secret....

Offline Ep128

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Re: Capacitors - wrong orientation?
« Reply #46 on: 2020.October.12. 22:56:45 »
Remember its first name: Damp Proof Course.

The first phases of development were strictly secret....
THEN. :-) But there could have been photos, recollections at the time that could be put together before being ISSUE3. But we don't know ...

Online gflorez

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Re: Capacitors - wrong orientation?
« Reply #47 on: 2020.October.13. 10:31:22 »
Not so long ago Tutus was honoured to ask Nick Toop some questions.

On his answer he narrates how painfully was his exit from Enterprise Computers LTD:

".....when I was constructively forced out of the company was one of the saddest periods of my life and I do not like to think about it.  I was also obliged to erase all personal copies of the design which is sad as I had various enhancements in mind and would love to be able to implement my design with these enhancements in a modern CPLD...."

This mean to me that all people involved on the project had such obligatory clause in their contracts.
« Last Edit: 2020.October.13. 10:34:49 by gflorez »

Offline Judge

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Re: Capacitors - wrong orientation?
« Reply #48 on: 2020.October.22. 19:57:47 »
I replaced the C9 capacitor on my 64/128 motherboard with a bipolar one. Working perfectly.

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Offline elmer

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Re: Capacitors - wrong orientation?
« Reply #49 on: Yesterday at 04:20 »
I replaced the C9 capacitor on my 64/128 motherboard with a bipolar one. Working perfectly.

Excellent, that is great to see. :)

I am very jealous of that beautifully clean motherboard! ;)

Offline Allf

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Re: Capacitors - wrong orientation?
« Reply #50 on: Yesterday at 07:56 »

Quote
I replaced the C9 capacitor on my 64/128 motherboard with a bipolar one. Working perfectly.
The electronics supplier in Poland currently only has a voltage of 6v3 (at a reasonable price) in stock, which I do not want to order. What is the voltage at the poles of the bipolar capacitance?

Offline BruceTanner

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Re: Capacitors - wrong orientation?
« Reply #51 on: Yesterday at 13:28 »
What is the voltage at the poles of the bipolar capacitance?
I put a 6.3v bipolar in my EP128, so far no problems. On an oscilloscope the voltages across it are exactly the same as with the original mono-polar (if that's the right word!) ie. goes briefly to 1V at power-up and then drops to a steady approx -1.25V - see my 'scope traces earlier in this discussion, I could observe no difference.

Offline Judge

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Re: Capacitors - wrong orientation?
« Reply #52 on: Yesterday at 13:56 »
Bruce was faster. :)  I measure -1150mV at the poles. My capacitor is a Nichicon 100uF 25v.
The output 12V is only 11.95V ... but still the picture is very nice.

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« Last Edit: Yesterday at 14:42 by Judge »
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Offline Allf

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Re: Capacitors - wrong orientation?
« Reply #53 on: Yesterday at 14:57 »
Thank you for your answers. I ordered 6V3 bipolar capacitors...

Offline Judge

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Re: Capacitors - wrong orientation?
« Reply #54 on: Yesterday at 21:07 »
I also replaced the C9 capacitor in my main machine with a bipolar one.

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The original capacitor was a Rubycon 100uF 10v, This capacitor is 99uF even after 35 years. The Japanese know something ... :smt023

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