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From: "Don" <g@crcomp.net>
Newsgroups: sci.electronics.design
Subject: Re: CoB LED filament analysis
Date: Sat, 25 Apr 2026 22:56:45 -0000 (UTC)
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john larkin wrote:
> Don wrote:
>> Don wrote:

<snip>

>>Game over. Lessons learned:
>>
>> 1. Pease hated solderless breadboards for a good reason: they introduce
>>    stray capacitance. After the solderless breadboard is removed the
>>    filament's current curve reverts to its true form with voltage and
>>    current in phase.
>
> 10 pF maybe. A million times less than would explain what you are
> seeing.
>
> But yes, the plastic solderless things are awful.
>
> https://www.dropbox.com/scl/fi/pk2t79ipe26c62lw9xi82/Z412_Proto.JPG?rlkey=jypa4wdmgqsvwu0l51rx1x445&raw=1

Bravo! If I remember correctly, you use a dental drill? My own freehand
dremel on copper isn't nearly as straight. Perhaps my new milling table
[1] will help.
    My media tends towards universal board. As an artiste associate,
appreciate my abstract art arrangement:

    <https://crcomp.net/ledfilament/circuit.png>

Note how voltage and current perfectly align after the solderless 
protoboard is swapped out and replaced by my abstract art arrangement:

    <https://crcomp.net/ledfilament/curveprobe3.png>

There's little, if any, wriggle room for the phase anomaly to caused by
anything other than stray capacitance from the solderless breadboard.

Note.

[1] <https://www.vevor.com/rotary-table-c_10128/compound-milling-machine-work-table-2-axis-cross-slide-bench-drill-vise-fixture-p_010230619047>

Danke,

--
73, Don, WD7Q                                             veritas    _|_
                                                          liberabit   |
https://www.qsl.net/wd7q                                  vos         |