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Cydrome Leader <presence@MUNGEpanix.com>: Oct 02 06:20PM > the solder using a heat gun on a low setting moving rapidly over the > joints. It seemed to work but it's very difficult to tell if all the > pins are making good connections with the pads.   I suggest getting a flux pen and name-brand solder braid and trying what's called "drag soldering". There are videos on youtube of the process. It's as magic as it looks, but the flux and clean solder is mandatory.

"Ian Field" <gangprobing.alien@ntlworld.com>: Oct 02 09:18PM +0100 "bitrex" <bitrex@de.lete.earthlink.net> wrote in message news:560d6fe2$0$29139$4c5ecfc7@frugalusenet.com... > removing the USB connector completely and using jumper wires to ensure > that all the pads are connected properly to the respective pins and have > continuity Suggestions?   I'd carefully dismantle what's left of the USB plug and clean up the solder pads for its pins. Next - wade in with an illuminated strong magnifier and try to identify whether any tracks leading away from those pads are broken.   Its probably easier to cut the plug end from a USB extension lead and wire that onto the flash drive PCB. Cutting the lead from a scrap item like a printer that runs from a separate supply probably won't work - they usually don't have the supply pin wired in the USB plug/lead.

Joe Gwinn <joegwinn@comcast.net>: Oct 02 04:32PM -0400 In article <87udnWLEJ8BXNZDLnZ2dnUU7-WmdnZ2d@giganews.com>, Jon Elson > Absolutely not worth it to just make it useable, but you may be able to get > the data off it this way, with careful handling. it is likely to be real > fragile with the cable soldered on to it.   I'd glue the busted thumb drive and the cable to a piece of wood, to protect the cobbled connections.   Joe Gwinn

DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org>: Oct 02 06:09PM -0400 On Fri, 02 Oct 2015 16:32:30 -0400, Joe Gwinn <joegwinn@comcast.net> Gave us: .snip   >I'd glue the busted thumb drive and the cable to a piece of wood, to >protect the cobbled connections.   Tie wraps.

Jasen Betts <jasen@xnet.co.nz>: Oct 03 09:28AM On 2015-10-01, bitrex <bitrex@de.lete.earthlink.net> wrote: [thumb drive repair]   > thinking of removing the USB connector completely and using jumper wires > to ensure that all the pads are connected properly to the respective > pins and have continuity Suggestions?   Drives of this type often have separate storage and usb-interface chips. the symptoms you describe could be explained by a USB connection that's working and storage that isn't.   Could be a solder joint, pcb trace, wire bond or die failure.   -- \_(ツ)_

DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org>: Oct 03 11:49AM -0400 >chips. the symptoms you describe could be explained by a USB >connection that's working and storage that isn't.   >Could be a solder joint, pcb trace, wire bond or die failure.   Except that the entire initial failure was simply the connector.   How is it suddenly that you think connections elsewhere are severed?

Fred McKenzie <fmmck@aol.com>: Oct 02 06:27PM -0400 Uniden BC-GPSK Serial GPS Receiver plugs into the serial port of my Ham Radio. It uses a power adapter built into a 12 Volt lighter plug, that converts 12 Volts DC into 5 Volts DC 1 Ampere. It has a one Ampere fuse.   After 6 months the GPS stopped working, fuse was blown. Replacement fuse blew immediately. Opened up the adapter and found a shorted transistor. There is also an unmarked 8 pin IC. Even if the transistor is replaced, it still might not work. So I built up a tab-mounted 7805 regulator with a couple of capacitors for stability.   Added some heat sinking, expecting the GPS to draw nearly an Ampere. Guess what? After hooking the GPS back up, the 7805 barely gets warm. Temperature is about 10 degrees F above ambient. In other words the original power adapter was greatly over specified for current. I suspect a 78L05 would have been sufficient.   The designers must have found it expedient to use an off-the-shelf adapter, even though it has reduced reliability and they did not need the available current.   Fred

Jeff Liebermann <jeffl@cruzio.com>: Oct 02 05:41PM -0700 On Fri, 02 Oct 2015 18:27:05 -0400, Fred McKenzie <fmmck@aol.com> wrote:   >Uniden BC-GPSK Serial GPS Receiver plugs into the serial port of my Ham >Radio. It uses a power adapter built into a 12 Volt lighter plug, that >converts 12 Volts DC into 5 Volts DC 1 Ampere. It has a one Ampere fuse.   The cancer stick socket to 5V adapter outputs to a USB port. There are specialized chips for the purpose, which include device detection, short circuit protection, and current limiting. In other words, they do more than supply 5VDC. While just 5V might be sufficient for your GPS receiver, it would not be acceptable for a smartphone, tablet, or other device that depends on a USB interface chip to identify the charger capabilities.   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

Phil Allison <pallison49@gmail.com>: Oct 02 11:52PM -0700 Fred McKenzie wrote:   > The designers must have found it expedient to use an off-the-shelf > adapter, even though it has reduced reliability and they did not need > the available current.     ** Your story reminds me of an issue that cropped up when the first portable CD players appeared the mid 1980s.   Folk liked to use them in their cars and wanted a DC adaptor for the job - one that plugged into the lighter outlet. Sony and Pioneer offered custom adaptors to go with their machines but for a steep price. The spec needed was 4.5V at 1 amp - but with a trap.   Generic brand car DC adaptors were available too, for well under half the Sony price with switchable output voltages of 9, 6 and 4.5V, with a 1 amp rating - so why not use one of them ?   When tried with a generic adaptor, the player worked - but soon as you hit the "skip track" button stopped. An on/off cycle was then needed to get it going again.   Reason was when track skipping, the machines drew a brief surge of about 3 amps which the generic adaptor could not supply. Plus, if the slide switch was ever set at 9V = instant destruction of the player OR if the puny transistor inside got too hot and failed short = same result.     .... Phil                                       bra

Chuck <chuck@mydeja.net>: Oct 02 04:43PM -0500 On Fri, 02 Oct 2015 09:15:59 -0700, Jeff Liebermann <jeffl@cruzio.com> wrote:   >If you go down the list, most are for 220VAC, but some include a >choice of voltage, such as: ><http://www.ebay.com/itm/281374270229>   The coiled ones on the ceramic form look drastically different from the "bird nest" ones that are used in the X-tronics station. I noticed that they both have the same plug so they could be interchangable.   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

Jeff Liebermann <jeffl@cruzio.com>: Oct 02 03:39PM -0700 >the "bird nest" ones that are used in the X-tronics station. I >noticed that they both have the same plug so they could be >interchangable.   Yep. My guess(tm) is that the ceramic form flavor does a better job of supporting the nichrome wires than the free form tangle of wires. My favorite way of destroying heater wires is to drop the device while it's red hot. The creamic form does block the air flow more than the free form flavor, so there may be a problem if you like to use high levels of air flow. I don't because it spreads the heat over too large an area on the PCB. At $10/ea, it's cheap enough that one could buy one of each type and experiment.   I just looked inside my 852d hot air gun and found that it uses a ceramic heater form.   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

Bill Martin <wwm@wwmartin.net>: Oct 02 11:15AM -0700 On 10/01/2015 04:52 PM, Tom Miller wrote:   > Also, you will need to figure out how to fab some new feet as the > originals are most likely gone.   > Good luck and 73   Thanks for that, and yes, the feet on both my scopes are falling apart.   Bill

"Ian Field" <gangprobing.alien@ntlworld.com>: Oct 02 06:40PM +0100 Anyone know where to find service info for this shaver?   The online reviews suggest that battery longevity isn't so good, but I got it on a free recycling group, so the rechargeable cell should have been cycled to its peak condition by now.   While the heads were in the ultrasonic cleaner - I removed the "pan" under the heads, but all I got at was the comfort adjustment mechanism, it not obvious how to split the case and examine the battery, it was pretty fiddly as far as I got, so I'd like to get the service info before delving any deeper.   Thanks for any help.

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