---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Tue 09/19/23: 2 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 10:55 AM - OVM-14 MkIII (Robert L. Nuckolls, III) 2. 11:14 AM - Battery 'desulfator'/pulse-repair (Robert L. Nuckolls, III) ________________________________ Message 1 _____________________________________ Time: 10:55:47 AM PST US From: "Robert L. Nuckolls, III" Subject: AeroElectric-List: OVM-14 MkIII As promised, I trimmed up a proposed schematic and part values list for the MKIII OVM-14. I could not devise a practical way to us a FET for the crowbar switch and still retain the original 2-wire functionality. Did find a suitable, sensitive-gate SCR that would work. Got a few things to clean up on the drawing and some notes to add. I'll get it published to the List yet today or in the morning. Need you guys to 'comb' it for bugs. I think I can get the parts to fit on a board not much bigger than the original OVM . . . decided to stay with a board-under-heat-shrink with flying leads. Simple, effective and low cost. This version has a feature I probably should have included in the original series of CB-OVM products . . . a press-to-test function. Past products had to be 'bench tested'. Given the very low parts count and robustness of parts, it was exceedingly unlikely that they would fail within the lifetime of the airplane . . . yet . . . being able to periodically verify functionality without removing from the airplane would be 'handy'. Bob . . . //// (o o) ===========o00o=(_)=o00o======== < Go ahead, make my day . . . > < show me where I'm wrong. > ================================ In the interest of creative evolution of the-best-we-know-how-to-do based on physics and good practice. ________________________________ Message 2 _____________________________________ Time: 11:14:19 AM PST US From: "Robert L. Nuckolls, III" Subject: AeroElectric-List: Battery 'desulfator'/pulse-repair I cruised around on youtube while on the trip out west . . . there's a bucket-load of videos on a constellation of battery recovery techniques claiming to recover batteries ranging from 'just a bit tired' to 'retrieved from salvage'. A variety of techniques included replacing electrolyte with Epsom salts, shocking with 50-200 amp chargers and praying over them with various versions of 'smart chargers'. Some demonstrations were marginally beneficial (previously dead battery would now start an engine) to one demo that claimed recovery to 80% of new. The most important thing missing from ALL the demonstrations was DATA secured by CAPACITY TESTING and LOAD TESTING. Just as a hedge on bolstering my own understanding for the current state of art and science in battery maintenance, I wrote to the Battery Guru at Battery University to inquire of the latest. Here is his reply: Bob, There was so much written of sulfation but no one has a simple solution. We are working with military organizations to also get a better insight into dormant lead acid batteries. Universities are also working on sulfation reversal. It is possible but not always practical. Please see also: https://batteryuniversity.com/article/bu-804b-sulfation-and-how-to-prevent-it Good luck and best wishes, Isidor Buchmann| CEO Cadex Electronics Inc. 22000 Fraserwood Way, Richmond BC V6W1J6 604.231.7777 phone | 604.231.7755 fax | www.cadex.com So . . . as of this point in time we can confidently assert that there is yet no documented, repeatable experiment supporting a notion that any products or processes can claim great strides in battery maintenance. Particularly batteries intended for use in aircraft. For us, marching orders are to USE and MAINTAIN a battery so as to minimize irreversible damage to the chemistry . . . and to swap out any battery that does not meet minimal design goals for continued airworthiness. Bob . . . //// (o o) ===========o00o=(_)=o00o======== < Go ahead, make my day . . . > < show me where I'm wrong. > ================================ In the interest of creative evolution of the-best-we-know-how-to-do based on physics and good practice. ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message aeroelectric-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/AeroElectric-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/aeroelectric-list Browse Digests http://www.matronics.com/digest/aeroelectric-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.