NB: everybody knows that the internal resistance of a battery varies with the concentration of the electrolyte ![Laughing :-DD](https://www.eevblog.com/forum/Smileys/default/smiley_laughing.gif.pagespeed.ce._hfWAz_QHO.gif)
Everybody? Absolute rubbish. Most one year old babies would not even know what a battery is, let alone anything about the internal resistance varying with the concentration of the electrolyte. Even Justin Beiber who is "worth" $200 million might not know either. In fact, it would not surprise me that less than 1% of the world's population know.
The tone of some of the comments in this thread reminded me of when I walked into an electronic components store in 1979 to buy a replacement 6X5 vacuum tube (valve) for my Kikusui oscilloscope for $2.15. The old valve's filament had gone open circuit. Another customer, whom I had never met before, was standing next to me. He big noted himself and belittled me by raising his voice in public something like, "A 6X5 valve is a bridge rectifier valve! Why don't you just use a couple of diodes! You're hopeless. Ha Ha Ha. I guess we all had to start somewhere." Embarrassed as I was, I was tempted to give this know-all a black eye. Instead I tried to explain I did not have a schematic for the oscilloscope and it was not worth the time mucking around, but this bombastic clown just laughed in contempt.
Assuming someone else hasn't already "taken him out" in a drive-by shooting or laced one of his junior burgers with cyanide, it would be poetic to find he is has been long term unemployable due to his inability to get along with people. I went on to become an electronics engineer as a life long career, and whilst I don't know it all and am learning all the time, I certainly know a lot more than I did in 1979. I have come across similar dick heads to Mr. 6X5 in business, but fortunately they are rare. I fired one once.
By the way, analysing Mr. 6X5's argument of using the rectifier diodes...
- I would need a schematic to the oscilloscope or a valve datasheet to work out where the diodes go
- I would need two diodes that are rated for the PIV, and current drain for B+ line in the oscilloscope
- I would probably need some resistors as well
- Back then diodes were not that cheap, around 60 cents each
- Spending an afternoon for the sake of saving $1, hoping I got it right is not time put to good use. Instead with the 6X5 valve, I just plugged it in and the Kikusui came back to life.
- The new 6X5 would have outlasted the old oscilloscope anyway
So even if it happened today, I would have done the same thing in buying the 6X5 valve. The only thing different is I would have wiped that smile off Mr 6X5's face
![Fighting :box:](https://www.eevblog.com/forum/Smileys/default/fighting0030.gif.pagespeed.ce.H3HVtgjLEV.gif)
(I am not saying you guys are like Mr. 6X5, but I do come across them electronics and programming weblogs and on Youtube. I think it is called trolling.)