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Phil Allison <pallison49@gmail.com>: Feb 01 12:00AM -0800 Hi,   few here would disagree that using an ESR meter is the fastest and surest way to find bad electros. If the meter reading is several times or more higher than normal, that electro must go.   This week, I saw a Fender tube amp with pretty obvious filter electro trouble that almost caught me trusting my (Bob Parker) ESR meter too much.   Under a steel cover were five, "IC" brand 22uF, 500V axial electros - from the symptoms I figured ones immediately following the rectifiers diodes must be bad. The ESR meter agreed, giving open ( >100ohms) ESR readings for two and good readings for the remaining three.   While extracting the bad pair from the PCB, I realised they were wired in parallel. The electros looked in good condition so my suspicions raised, I peeled back the case with nippers to loosen rubber bung and take peek inside.   Turned out there was NO metallic connection between the positive lead and the rest of the capacitor. The bung and lead stub simply fell off. I opened the other three and found two more in the same condition while the last was perfectly OK with all its connections in place.   The electros concerned are exactly like the ones in this pic:   http://www5.austlii.edu.au/au/legis/qld/consol_act/cc189994/s268.html   The ESR meter was fooled by the fact (except for one) the caps had NOT gone high ESR, but had suffered severe corrosion of the plus leads where they entered the cap roll.   I have to agree with the author of the linked page, Illinois Capacitors have produced a bad batch and full replacement is the only smart option.         .... Phil

Phil Allison <pallison49@gmail.com>: Feb 01 12:03AM -0800 Phil Allison wrote:   -------------------   ** Ooops - wrong link !!!   The electros concerned are exactly like the ones in this pic: http://billmaudio.com/wp/?page_id=267     .... Phil

jurb6006@gmail.com: Feb 01 12:20AM -0800 Actually the ESR meter was correct. The effective series resistance was provided by the gap in the wiring.

Phil Allison <pallison49@gmail.com>: Feb 01 12:38AM -0800 jurb...@gmail.com wrote:   ---------------------   > Actually the ESR meter was correct.     ** The good reading was **misleading** you fucking moron.       .... Phil

John-Del <ohger1s@gmail.com>: Feb 01 07:22AM -0800 On Thursday, February 1, 2018 at 3:00:29 AM UTC-5, Phil Allison wrote: > Hi,   > few here would disagree that using an ESR meter is the fastest and surest way to find bad electros. > .... Phil     Handy. Yes. Useful. Yes.   Surest? No.   Just replaced a surface mount 33uf/25v on an LG sustain EBR31872801 board which had image persistence issues and rash. The board would show improve in operation with heat added to the board. Because of the amount of sm electros on the board, I used my ESR meter with tweezer probes as removal of surface mount electros for testing is not practical. C49 33uf/25v checked about a half ohm in circuit so I moved on. The rest of the sm electros on the board checked fine as well. After I found the problem with the scope, I tested the defective cap for shits and giggles and it read good value but >300 ohms ESR out of circuit. Before installing the replacement cap, I took an ESR reading of the empty lands and it read half an ohm. The only other cap parallel to it is C43, a 1uf surface mount film cap with an ESR of ....... 0.5 ohms.

bruce2bowser@gmail.com: Jan 31 10:07PM -0800 > e) That some cures require exterior stimulus is a factor. > f) And some low-end epoxies will crystallize, one part especially, even when fresh with a single exposure to low temperatures.   > During the summer, my hobby room will undergo pretty wild temperature swings.   That sounds almost like the direct opposite of a wine cellar, which is kept at a certain temperature year-round for years. Even decades.

"(PeteCresswell)" <x@y.Invalid>: Jan 31 01:44PM -0500 Per mike: >Bottom line...go buy a new battery.   I think it's finally starting to soak in....   Thanks for the detailed account. -- Pete Cresswell

N_Cook <diverse@tcp.co.uk>: Jan 31 11:38AM On 30/01/2018 14:55, (PeteCresswell) wrote: > cells   > - Replace the old cells with new cells   > - Close up the case   Check the charger as well. A nimh version I looked at recently, intermittent shorted wires on the the charger had drained the battery to internal dendriting or such.

MOP CAP <email@domain.com>: Jan 31 02:50PM -0800 My sone has posted the catalog sheet I promised on   http://www.bartlettstreet.com/electronics/PotTapers.jpg   CP

Fox's Mercantile <jdangus@att.net>: Jan 31 05:22PM -0600 On 1/31/18 4:50 PM, MOP CAP wrote: > My sone has posted the catalog sheet I promised on   > http://www.bartlettstreet.com/electronics/PotTapers.jpg   > CP   Thankies   Heh, and not a single K or W in the list. ;-)     -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

Phil Allison <pallison49@gmail.com>: Jan 31 06:59PM -0800 Fox's Mercantile wrote:   --------------------------     > > http://www.bartlettstreet.com/electronics/PotTapers.jpg   > Heh, and not a single K or W in the list. ;-)   ** Not a single mention of any of the time honoured code letters for tapers either.   FYI:   This wiring diagram for a late 60s Fender is instructive:   http://www.kbapps.com/audio/schematics/tubeamps/fender/vibroluxreverbab568layout.php   In order from the left, the pots are labelled:   50K RA, 3M RA, 100K L, 250K A, 250K A, 1M A, 250k A, 250K A, 1M A.   where RA = reverse audio, L = linear and A = audio.     The "3M RA " pot adjusts the phase shift oscillator part of the "Vibrato" circuit. Luckily, a 2M linear pot does the job at a pinch.       .... Phil

Ivan Vegvary <ivanvegvary@gmail.com>: Jan 31 04:40PM -0800 Just rebuilt this saw. Electronics worked when purchased used in 2005. Now, with new battery, nothing on the display. Total of 4 encoders should be read/displayed. Any help on finding schematic etc. appreciated. Sears no longer has parts. Thanks!

"Ron D." <ron.dozier@gmail.com>: Jan 31 03:16PM -0800 Too much free play causes the clutch pedal to "bounce". e.g. The difference between the pedal at the up stop and start of engagement.   Push rod play is contact to resistance.   A bad throwout bearing will totally mess up the feel you expect. It will feel sloppy.

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