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Abe D <abednpspam@verizon.net>: Feb 02 02:47AM -0500 I have a broken circuit board and accompanying topside components here:   https://imgur.com/a/Pbt1HSU   The red circled areas show the cracked sections. In a pinch, I have glued the broken parts back together with JB Quick Weld. After several hours, it seems stable enough to handle.   Now, the question is, what's the best way to rejoin the broken traces? Initial thought was to just jumper over the solid sections and join the jumpers between soldered components. Not so sure what to do about the large screened sections (probably serving as a ground screen for the flyback topside?). I welcome any tips or thoughts. If I start trying to scrape the conformal coating, it may come apart again.   Unfortunately, the board cannot be replaced.   Thanks in advance.   Abe

micky <NONONOaddressee@rushpost.com>: Feb 02 03:24AM -0500 In sci.electronics.repair, on Sun, 2 Feb 2020 02:47:18 -0500, Abe D   >Now, the question is, what's the best way to rejoin the broken traces? >Initial thought was to just jumper over the solid sections and join the >jumpers between soldered components.   Sounds good.   > Not so sure what to do about the >large screened sections (probably serving as a ground screen for the >flyback topside?).   I'm no pro, but why not the same thing. Does it matter if the edges of the screen are touching if the screen itself is all connected to itself. Then you can see if the thing it comes from works or not.   40 years ago I had a roommmate whose father threw a clock-tv at him. I neve saw another one. So cute. 9" TV, I would have liked to have had one. Board was broken in about 20 places but it worked after I jumpered each of them.

John-Del <ohger1s@gmail.com>: Feb 02 05:32AM -0800 On Sunday, February 2, 2020 at 2:47:22 AM UTC-5, Abe D wrote:   > Unfortunately, the board cannot be replaced.   > Thanks in advance.   > Abe   It's too late now but repairing board with a topical coating of epoxy is not the way to stabilize it. The epoxy acts like a top hinge and the bottom of the board will flex away from the crack. To make it more stable, you have to add some epoxy on the other side and hope it adheres.   The proper way to repair a fractured board is to remove any component(s) that crosses the break, and fit the board pieces back together where the seam doesn't even show. You may actually have to break the board a bit more to get it to fit perfectly.   At this point, apply FRESH cyanoacrylate so it wicks inside the fracture and bonds the board completely together from the inside, not just one side.   If done properly, the cracks will be barely visible. Scrape the green mask off the trace just at the break and half the distance the trace is wide. A drop of solder across each land will finish it.   In your case, because the pieces don't fit that well, scrape back the mask and hand wire from point to point and across the fracture with some fine copper stranded wire (one or more strands depending on width of the trace), and coat the entire trace with solder using the copper strand as a sort of "rebar".   Deflux the board and apply either a conformal coating or get some green nail polish to protect the lands.

micky <NONONOaddressee@rushpost.com>: Feb 02 12:41AM -0500 In the attic, my co-ax F-connector has separated from the coax, and because of the age, 35 years, and the occaisional heat**, the white vinly covering doesn't strech enough to replace the F-connector.   What to do?   I can strip the outer vinyl back and then just crimp on the braid. Would that be okay?   If not, what? Running a new cable is almost beyond me now that I'm 35 years older.       **Roof fan all this time which kept it undder 85 or 90, except a few days when the fan was broken.

John-Del <ohger1s@gmail.com>: Feb 02 05:22AM -0800 On Sunday, February 2, 2020 at 12:41:24 AM UTC-5, micky wrote: > years older.   > **Roof fan all this time which kept it undder 85 or 90, except a few > days when the fan was broken.     First determine if it's RG59 or 60, then acquire the appropriate connector. Cut off the old end and strip back to fresh copper and braid. If you don't have a crimping tool and don't want to invest in one, you can get thread on type F connectors.   https://www.amazon.com/GE-Coaxial-Connector-Weather-73512/dp/B003YKG9FS   If you must do it this way, I'd give it a little coating of dielectric grease before threading it all together.   Probably last 10 to 20 more years assuming the cable is in good shape.

jaugustine@verizon.net: Feb 02 07:26AM -0500 >> Thank You in advance, John   >Guess this is the stripped/desk version of the 200XLT handheld. >Manualslib has a service manuals for the the 200XLT   Hi, This is NOT a handheld unit. I should have mentioned that. John

etpm@whidbey.com: Feb 01 05:14PM -0800 Hey All, I have a lathe with a FUJI-FRENIC Spindle Drive. The machine dates from the lathe 1980s. Today there was a big power surge and one of the 3 MOVs on the input for the drive exploded. A "Super Rapid Fuse", also made by Fuji, blew too. I cut off the bad MOV, replaced the fuse, and the drive works again. Yay for MOVs and Super Rapid Fuses. But I can't find the data for the MOV so I can buy a new set of 3. There are 2 MOVs left in the drive that can be read, the exploded one is completely unreadable. The marking on one MOV is ENB401 40. The other one is marked ENB401 48. I looked at the markings and there is no mistake, one is marked 40 and the other 48. The way the MOVs are mounted in the drive makes it obvious that they were installed as a set. 3 MOVs and 3 capacitors have their leads crimped together into lugs so that the whole assembly can be mounted to 3 screws on the terminal block that holds the fuses. Looking for datasheets all I can find are ENB401D numbers with other numbers that follow the ENB401D characters. So I just don't know how to cross reference what I have to what is available now. Apparently the diameter of the MOV is important as part of the rating. Mine measure 16MM but that is measuring over clear heat shrink so I think the disc inside is actually 14MM. Can anybody here help? Please? I can run the machine without one of the MOVs but I am reluctant to do so, especially because of the weather we are having that is causing the power outages and surges. Thanks, Eric

J-J <none@none.non>: Feb 01 03:18PM -0500 >> under $10, am I?   > If you're willing to experiment. I gave you a clay-free rubber stamp ink formula that costs nothing to make. I've not tried it in your app.   > NT   Yes, I guess you did. Unfortunately, I don't think I have any of that stuff on hand. All I might be able to obtain is mineral oil later today. Maybe I could try mixing a drop of that with the ink?   Well, the good news is that a VERY thin trace was made over a one day period using nothing other than the Staples oil based ink and my packing taped backed printer paper. Enough of a trace with falling barometric pressure that I could see that the barograph at least works. I would still like to get week's trace out of it though. I suspect the paper I've devised isn't very absorbent, so any cheap modifications I could try in a pinch would be welcome. Perhaps doubling (or tripling) up the sheets next time around?

J-J <none@none.non>: Feb 01 03:20PM -0500 > Oh, I remember an ink experiment ... vegetable oil & powder toner. Soot is also usable but not nearly as convenient, as there is the issue of particle size.   > Anyway, why not use a biro?   > NT   What's a biro?

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