Talk:Load line (electronics)

Latest comment: 2 years ago by Johnuniq in topic Unclear wording

2012 edit

this is a small circuit but we can learn more things about linear & non-liner resistance. what is load line?load+line as electric ko load and splay to line — Preceding unsigned comment added by 14.194.49.65 (talk) 04:36, 10 October 2012 (UTC)Reply

Blacklisted Links Found on the Main Page edit

Cyberbot II has detected that page contains external links that have either been globally or locally blacklisted. Links tend to be blacklisted because they have a history of being spammed, or are highly innappropriate for Wikipedia. This, however, doesn't necessarily mean it's spam, or not a good link. If the link is a good link, you may wish to request whitelisting by going to the request page for whitelisting. If you feel the link being caught by the blacklist is a false positive, or no longer needed on the blacklist, you may request the regex be removed or altered at the blacklist request page. If the link is blacklisted globally and you feel the above applies you may request to whitelist it using the before mentioned request page, or request it's removal, or alteration, at the request page on meta. When requesting whitelisting, be sure to supply the link to be whitelisted and wrap the link in nowiki tags. The whitelisting process can take its time so once a request has been filled out, you may set the invisible parameter on the tag to true. Please be aware that the bot will replace removed tags, and will remove misplaced tags regularly.

Below is a list of links that were found on the main page:

  • http://electronics.indianetzone.com/1/analysis_of_dc_load_line.htm
    Triggered by \bindianetzone\.com\b on the local blacklist

If you would like me to provide more information on the talk page, contact User:Cyberpower678 and ask him to program me with more info.

From your friendly hard working bot.—cyberbot II NotifyOnline 19:01, 8 December 2013 (UTC)Reply

  Resolved This issue has been resolved, and I have therefore removed the tag, if not already done. No further action is necessary.—cyberbot II NotifyOnline 06:09, 12 December 2013 (UTC)Reply

Transistor load line edit

The section and the figure are very poor. The transistor load line is important for the topic, so I don't want to delete it, but I don't want the reader to believe the section is anywhere near accurate. The text depends on the figure, but the figure shows that saturation cannot be anywhere near VCE=0. Glrx (talk) 05:26, 18 May 2017 (UTC)Reply

Could you not just fix the text? I wonder if I can edit the figure - what would you like to see changed in the figure? --Wtshymanski (talk) 16:30, 18 May 2017 (UTC)Reply
Looking at my old textbook, now I see the problem - the transistor curves start off at the left in saturation and then head out as roughly constant current lines, but the figure marks the point crossing Vce=0 as saturation. I wonder if I have a .PNG editor? I could take off the word "saturation" where the load line crosses Vce=0. --Wtshymanski (talk) 17:23, 18 May 2017 (UTC)Reply
After getting a bunch of propeller-head error messages when I tried to upload an .SVG, here is a (non-editable?) .PNG. How does this look? ---Wtshymanski (talk) 21:21, 18 May 2017 (UTC)Reply
File:Draft for review BJT CE load line.png
For discussion.
After spending the last hour learning all about the "Black rectangle (Flowed Text bug)", I've put a revised figure on the page. (Hint: using Inkscape as designed, you still produce files that are garbage when uploaded to Commons. You have to use the XML editor to manually remove any flowed text boxes that you've accidentally created, but can't see in Inkscape. With such a convenient work around, no wonder this bug hasn't been fixed in 7 years.) Drat, I've used a san-serif font and the previous illustration uses a serif. More fixing needed. --Wtshymanski (talk) 21:43, 20 May 2017 (UTC)Reply
I fixed some of the text but didn't have time to work on the rest (which needed a better figure) or the figure itself. The issue with the axes confuses both the saturation and the cutoff issues. The points on the axes are the load line's open-circuit voltage and short-circuit current. There's no guarantee the transistor can reach either of those points. As you've noticed, VCE is far away from the axis. The cutoff voltage can be much closer to the axis. I'd like the figure to show Ib=0 and be visibly above the voltage axis to illustrate that possibility. The collector leakage current for Ge signal transistor (2N1304) was around 6 μA; that would be a 0.06 V drop with a 10 kΩ load resistor. Si signal transistor are better (2N708 is 25 nA). The leakage is worse at higher temps. The load line and transistor VICs don't look right: either the figure's transistor saturation voltage is unreasonably high or VCC is unreasonably low. I'd like the transistor curves to display an Early voltage slope. See 2n3904 curves at http://www.physics.csbsju.edu/trace/NPN.CC.html with its compressed left side and Early slope. (That webpage does not show Ib=0, so maybe I should not insist on such a curve. The 2N3904 leakage current would be nanoamperes.)
Yes, Inkscape introduces a number of problems. I've never used it, but I've looked at many of its (verbose) .SVG files. Many people run into the flowed text / black text problem. Font substitutions are also an issue; WM may not have the font and the substituted font, even if it is sans serif, may have much different character spacing. Commons:Help:SVG; esp. § on fallback fonts. The library used to generate PNG files from SVG, librsvg, has many bugs and limitations, but there are few alternatives for WMF. Sadly, making illustrations is difficult, and the tools often get in the way or have steep learning curves. Your SVG illustration has separately placed subscript text, but that should not be done. Inkscape should have a facility to italicize and subscript text within a string using tspan elements. (It can be done with CSS, but I doubt Inkscape allows that approach because it stuffs all its graphic context into per-element style attributes. Illustrations should also avoid text descriptions because they complicate translation.
Glrx (talk) 21:23, 22 May 2017 (UTC)Reply
But this article is about load lines, not the 2N3904 transistor. We already mention an "ideal" transistor in the text, which every prof keeps in the same stock room with the frictionless planes and massless pulleys. It would be far from the purpose of this article to go into the specifics of some random transistor. You notice there's no values on the axes. For illustration of the load line concept, it doesn't matter what the transistor saturation voltage is, and for clarity it's better to show the cureves with some distance to the current axis. I think my redraw of the figure has roughly the proportions of figure 4-16 in my old prof's transistor textbook, though he had one more IB curve shown. He didn't think he needed to show IB=0, either and he had a lot more space than this article has to explain load lines. --Wtshymanski (talk) 23:53, 22 May 2017 (UTC)Reply

Unclear wording edit

"and the voltage at the terminals of the diode must be the same" The same as what? Clearly the voltage at the diodes terminal (in reference to ground) are not the same. Also the voltage across the diode is not the voltage at the terminals. This phrase makes no sense. — Preceding unsigned comment added by 2003:c5:c704:a044:8993:f4e4:6f57:9e3e (talkcontribs) 05:11, 2 August 2021 (UTC)Reply

I clarified the wording. More could be added but that's somewhat leading to a textbook approach which is not Wikipedia's style. Johnuniq (talk) 06:53, 2 August 2021 (UTC)Reply