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micky <NONONOmisc07@fmguy.com>: May 02 11:50AM -0400 It pays to save electronics scrap. I needed a short piece of thin but not too thin single strand wire and I don't seem to have any except for a collection of 8 wires soldered into an octal plug from a 1930's (or 40's or 50's?) radio. (the kind of plug that uses a tube socket)   IIRC, I got this 40 years ago and I think I got it from someone else's scrap, so it's easily 60 years old. The red, blue, and brown wires are quite pretty but the yellow? wires seem very dirty. I wonder why.   It's actually not single strand but the entire length of the multi-strand is tinned.   Does that mean they used solder on 100's of thousands of miles of wire when only a teeny tiny bit ever appeared out of the insulation? Isn't that a big waste of tin and lead? Do they still do that?       Another interesting factoid: I needed to use for the first time some liquid rosin flux (in a little bottle from MG Chemicals). I've had it for 10 years unopened and it has one of those obnoxious caps that you have to press down before turning. No matter how hard I pressed down, it eventually ratcheted over what it was supposed to catch on. I tried over and over, last night. This morning it opened on the second try! The room temperature is about the same.

"Paul Hovnanian P.E." <paul@hovnanian.com>: May 01 06:41PM -0700 Stu jaxon wrote:   > yes, the switch/selector isn't stuck. the ohms display is , i might have > accidently tested a high voltage in the ohms setting, i don't remember. > just wanted to know if it's fixable. i google it, and found zilch...   How is it reading in the Volts ranges? These things have only one A/D converter and display. Everything else is input conditioning, range selection and (for ohms) a current source.   -- Paul Hovnanian mailto:Paul@Hovnanian.com ------------------------------------------------------------------ I live the way I type; fast, with a lot of mistakes.

Phil Allison <pallison49@gmail.com>: May 01 08:54PM -0700 Paul Hovnanian P.E. wrote: ====================   > How is it reading in the Volts ranges? These things have only one A/D > converter and display. Everything else is input conditioning, range > selection and (for ohms) a current source.   ** Hand held DMMs do not use current sources for resistance measurement.   Rather, they read the *ratio* of two voltages, one across the unknown part and the other across an accurate reference resistor. This is both simpler & far more accurate.   Also, they do not use normal A-D converters.   An analogue technique called " dual slope integration" converts the DC input voltage to a precise time interval. This interval is used to pass clock cycles from a time base which counted and displayed in decimal form.   The "digital " bit is only the display.     ..... Phil

Stu jaxon <stankowalski02@gmail.com>: May 02 06:24AM -0700 On Saturday, May 1, 2021 at 9:41:58 PM UTC-4, Paul Hovnanian P.E. wrote: > Paul Hovnanian mailto:Pa...@Hovnanian.com > ------------------------------------------------------------------ > I live the way I type; fast, with a lot of mistakes.   no problems in the volts range.

David Farber <farberbear.unspam@aol.com>: May 01 09:48AM -0700 On 5/1/2021 6:48 AM, Allodoxaphobia wrote: > or radiation exposure; you need to be aware of chemical poisoning.   > https://allthatsinteresting.com/engineer-accidentally-takes-lsd   > Jonesy   Great article!   Though one of the commenters suggested an alternate theory:   "It's also possible that the 'crust or a crystalline residue' was simply some old mold, as some forms of it can cause acid like trips. Coupled with the fact that the device was found in a 'cold dark closet... damp, lightless, conditions' it most certainly points to the mold theory rather than old LSD. By the way LSD does not survive for 50 years in a damp environment, if anything it only a dry moisture free storage. Not saying that the LSD find is impossible, but reading in between the lines of the article, one can conclude otherwise."   -- David Farber Los Osos, CA

John Robertson <spam@flippers.com>: May 01 10:38AM -0700 On 2021/05/01 9:48 a.m., David Farber wrote:   > -- > David Farber > Los Osos, CA   The more you learn, the less you think you know...   https://moldpedia.com/black-mold-symptoms   Fascinating!   Thanks,   John :-#)#

Tim R <timothy42b@aol.com>: May 02 05:02AM -0700 On Saturday, May 1, 2021 at 1:38:23 PM UTC-4, John Robertson wrote:   > Fascinating!   > Thanks,   > John :-#)# There is a famous episode of poisoning by the ergot fungus that caused major mental illnesses back in a small town in France in 1951.   Apparently a wet spring led to mold on the wheat, and hundreds of people became ill. Some never recovered.   https://en.wikipedia.org/wiki/1951_Pont-Saint-Esprit_mass_poisoning

Jason Bowers <jbbowersnospam@aol.com>: May 01 06:36PM -0400 After selling off a prior oscilloscope nearly two decades ago, I decided to pick up another used one. I have forgotten most of the functions. This is a used two channel 30 Mhz Elenco S-1325. I can return if it fails my testing.   All I did so far use a coax t adapter between an RF signal generator and a 50 ohm dummy load to channel the remaining side into one of the scope channels. I then set it for 28 Mhz and 100,000 uV output. After some fiddling, mainly because I forgot most functions, I finally got a nice sine wave of the approximate frequency. What other functions might I perform to make sure it is functioning ok?   Thanks.

Phil Allison <pallison49@gmail.com>: May 01 05:22PM -0700 Jason Bowers wrote: ================ > fiddling, mainly because I forgot most functions, I finally got a nice > sine wave of the approximate frequency. What other functions might I > perform to make sure it is functioning ok?   ** You need to buy or borrow a test oscillator, function or sine /square. Then you check each setting of the controls, one at a time. Square waves should look "square".   Vertical calibration can be checked with the help of any DMM on AC volts and a 400Hz sine wave. Horizontal calibration really needs a frequency counter, but the 50/60 Hz supply is very accurate .   Make sure the "trace rotation" controlactually works.     ..... Phil

Mike Coon <gravity@mjcoon.plus.com>: May 02 11:18AM +0100 In article <s6kl4j$ul6$1@dont-email.me>, jbbowersnospam@aol.com says... > sine wave of the approximate frequency. What other functions might I > perform to make sure it is functioning ok?   > Thanks.   Does it offer combinations of two channels, e.g. A+B; A-B. Latter differential could be checked with identical inputs and seeing how accurately you get zero!

Jeroni Paul <JERONI.PAUL@terra.es>: May 01 07:08PM -0700 El jueves, 29 de abril de 2021 a las 13:19:13 UTC+2, Miguel Giménez escribió:   > -- > Saludos > Miguel Giménez   Hi Miguel, I hope you are all well.   As others said this sounds like a problem with the speakers. The coil is glued to the plastic membrane and is now loose from one side. I have had luck fixing some of these speakers. Depending on the speaker construction it may be easier to pull the magnet or separate the membrane from the frame. Either way once you get access to the coil you can glue it back, I use two component adhesive. Make sure you glue it exactly at the original position. Once dry glue the magnet/membrane back, the magnet may need centering, for that I apply an audio signal while the glue is not dry and center it for a loud and clear sound.

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