From: nojunk@knology.net   
      
   On 7/6/2018 7:31 PM, amdx wrote:   
   > On 7/6/2018 6:17 PM, jurb6006@gmail.com wrote:   
   >>> "** For that to be the case, YOU have to know in ADVANCE what the   
   >>> acceptable ESR readings are for each electro you need to test."   
   >>   
   >> Not so much. The ones that are bad were stressed more, the others in   
   >> the unit of the same make and age may not have been and not as much of   
   >> the electrolyte has been boiled out. In circuits of the latter type,   
   >> ESR is not that critical. Nut with the high pass filter it makes the   
   >> value less important.   
   >>   
   >> So acceptable ESR readings are not going to be found on a chart.   
   >> What's more. my device does not actually read ESR in a lab type   
   >> fashion, it is meant more as a go/nogo tool to speed up   
   >> troubleshooting, even for those who can't really troubleshoot.   
   >>   
   >> Even in the user manual for this thing I would include to look at the   
   >> positive (or whatever) lead and look to see if it is green and to look   
   >> for any of them bulging. My goal is to keep as much of this stuff out   
   >> of the dumpster (skip) as possible.   
   >>   
   >>> "I regularly work on valve / tube amplifiers and am therefore   
   >>> familiar with ESR readings for high voltage electros in the range of   
   >>> 22 to 220 uF. No need to look up any lists and my spares stock is   
   >>> available to compare readings with new parts."   
   >>   
   >> With your experience you don't have to look up shit. you can say right   
   >> away, "This is good", "This is marginal" and "This is bad". But I do   
   >> realize that many, especially novices have not had that inculcated   
   >> into them.   
   >>   
   >> For them all I can say is change the worst first.   
   >>   
   >>> "For example, the 5 or 6 HV filter electros in most Fender tube amps   
   >>> can be checked and evaluated with a Bob Parker meter in under 1   
   >>> minute. The small cathode bypass ones take about another minute and   
   >>> you are done."   
   >>   
   >> Yeah, double or even triple the secondary voltage and the condition of   
   >> the caps becomes quite important.   
   >>   
   >>> "Of course, extremely old caps and any that show signs of having   
   >>> oozed electrolyte get replaced -  no questions."   
   >>   
   >> Have you noticed that most of them took a hell of alot longer to go bad ?   
   >>   
   >> Anyway, I think my doodad can be useful to novices as well as masters.   
   >> Very fast. In a power supply, clip one lead to ground and check all of   
   >> them, a minute ? That's like an 8086 compared to today's processors. A   
   >> minute to chack a cap ? That is an eternity.   
   >>   
   >> There is the Dick Smith, fine and good. But for servicing you don't   
   >> need to know between 1.7 and 1.8. Why ?   
   >>   
   >   
   >    Here's a video, most of it uses a scope to see the results of the   
   > test, but at the end of the video he does show test with results on an   
   > analog meter.   
   >> https://www.youtube.com/watch?v=115erzCCxgE   
   >   
   >                     Mikek   
      
   Found his analog design here. > https://www.youtube.com/watch?v=bmYAgat-sOQ   
      
                         Mikek   
      
   --- SoupGate-Win32 v1.05   
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