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etpm@whidbey.com: Nov 15 10:56AM -0800 The voltage from my generator drooped so much that a 3500 watt generator would no longer start a 1/4 hp motor. So I opened up the back of the generator and removed the voltage regulator so I could see the part number. Upon removal I see the ubiquitous bulged electrolytic capacitor. All the electronics are are potted into the reg case but the bad cap protrudes from the potting compound by about 5/8". Today I ordered a new reg but I am thinking that since the bad cap sticks up so far why not just remove the contents of the cap and peel the can out of the potting compound, thereby exposing the cap leads. Then just solder a new cap to the old leads or even directly to the circuit board if I can get to it. I think that I will end needing to solder a couple wires to the old leads and then solder the cap to the wires though. If this turns out to be the case will having the cap connected to wires that may end up being about 6 inches long be a problem? The cap in question is 220 MFD 250 volt. I will be replacing it with one that has a higher voltage rating. Eric

"pfjw@aol.com" <pfjw@aol.com>: Nov 15 10:56AM -0800 Given that the alternative is landfill, use your heat gun (wife's hair dryer or oven) to remove the guts from the case and replace what is needed. IT may not be just that cap.   If you slide the potted guts out of the case, you then may freeze it hard, and hit it with a hammer to shatter the potting. This may help you get to the individual components faster. Been there. Done that.   Peter Wieck Melrose Park, PA

John-Del <ohger1s@gmail.com>: Nov 15 11:13AM -0800 > cap in question is 220 MFD 250 volt. I will be replacing it with one > that has a higher voltage rating. > Eric   A lot of smps designs want the bypass electros as close to the secondary rectifier as possible. I don't suppose a good electro a few inches away will be as bad as one with high esr properly mounted, but it still might cause problems.   Unless it's an epoxy potting, you should be able to de-pot the board and get that cap in as it should.

rickman <gnuarm@gmail.com>: Nov 15 02:51PM -0500 > to wires that may end up being about 6 inches long be a problem? The > cap in question is 220 MFD 250 volt. I will be replacing it with one > that has a higher voltage rating.   No.   Electrolytic caps have fairly high ESR and inductance so that they will never notice the effect of 6 inches of wire.   --   Rick C   Viewed the eclipse at Wintercrest Farms, on the centerline of totality since 1998

Phil Allison <pallison49@gmail.com>: Nov 15 03:26PM -0800 Prickman complete moron wrote:   ---------------------------------   > Electrolytic caps have fairly high ESR and inductance so that they will > never notice the effect of 6 inches of wire.   ** Bullshit !!!   The Prickman keeps reposting the SAME bollocks he has been for decades.   Adding 6 inches of wire to an electro will massively increase its self inductance, by a factor of 10 at least.   The OP should add just enough wire to make connection to the PCB and twist the pair.     .... Phil

tabbypurr@gmail.com: Nov 15 04:07PM -0800 On Wednesday, 15 November 2017 23:26:21 UTC, Phil Allison wrote:   > ** Bullshit !!!   > The Prickman keeps reposting the SAME bollocks he has been for decades.   > Adding 6 inches of wire to an electro will massively increase its self inductance, by a factor of 10 at least.   which might or might not be a problem. I have a computer somewhere that had all its on-board supply caps replaced with the new ones hanging on wires. Works flawlessly.     > The OP should add just enough wire to make connection to the PCB and twist the pair.   Do what you can do.     NT

mike <ham789@netzero.net>: Nov 15 04:13PM -0800 On 11/15/2017 3:26 PM, Phil Allison wrote:   > Adding 6 inches of wire to an electro will massively increase its self inductance, by a factor of 10 at least.   > The OP should add just enough wire to make connection to the PCB and twist the pair.   > .... Phil   Put the biggest cap you can solder into the hole and parallel the wires to the external cap.

Phil Allison <pallison49@gmail.com>: Nov 15 04:42PM -0800 tabb...@gmail.com wrote:   ----------------------------   Prickman complete moron wrote:     > > The Prickman keeps reposting the SAME bollocks he has been for decades.   > > Adding 6 inches of wire to an electro will massively increase its self inductance, by a factor of 10 at least.   > which might or might not be a problem.     ** FFS - do you *read* posts at all????   How is that relevant to the Prickman's bullshit claim ?   FOAD       .... Phil

tabbypurr@gmail.com: Nov 15 05:21PM -0800 On Thursday, 16 November 2017 00:42:20 UTC, Phil Allison wrote:   > > > Adding 6 inches of wire to an electro will massively increase its self inductance, by a factor of 10 at least.   > > which might or might not be a problem.   > ** FFS - do you *read* posts at all????   yes   > How is that relevant to the Prickman's bullshit claim ?   it's relevant to the OP's situation   > FOAD   thanks charmer.     NT

Jeff Liebermann <jeffl@cruzio.com>: Nov 15 10:00AM -0800 On Wed, 15 Nov 2017 09:52:00 -0500, Bob Engelhardt >> <https://www.youtube.com/watch?v=tbEfhPbqTDE>   >I came away with this clever tip: use small magnets to hold test leads >to the ends of cells.   Yep. However, I suspect that may have been an accidental discovery. When one salvages 18650 cells from a laptop battery pack, the resulting cells do not have a projecting button top on the positive electrode. Getting such a cell to make a proper connection in a battery holder or flashlight is problematic. So, someone determined that a tiny magnet will stick to the positive terminal and provide a suitable button top contact (and test lead connection): <https://www.ebay.com/itm/New-15pcs-Battery-Magnet-Spacer-Convert-Flat-to-Button-Top-All-Lithium-ion-/282548150944>   -- 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

"Ian Field" <gangprobing.alien1@virginmedia.com>: Nov 15 06:44PM "mike" <ham789@netzero.net> wrote in message news:oug5uk$l7h$1@dont-email.me...   > That seems to contradict the statement the the only electronics is the > MOSFET. I don't know what to make of that... And something has to > control the MOSFET     Yes - a tact switch salvaged from the front panel of a Sky box.   > You're saying that the shunt regulator failing open can't harm the > battery?   It helps if you read before replying.   A shunt regulator failing short circuit (the most likely fault) wouldn't do the battery any good at all - A SB diode in the feed makes that accident unlikely.

"Ian Field" <gangprobing.alien1@virginmedia.com>: Nov 15 06:52PM "Jeff Liebermann" <jeffl@cruzio.com> wrote in message news:9kin0d5cmed4i9gngk1k9c21157nul3an8@4ax.com...   > Here's how to fix it: > <https://www.youtube.com/watch?v=IhUtKvCV6fs> > <https://www.youtube.com/watch?v=1w3Tv1Jg0ps>   Every day is a school day.   I might have to rummage those cells out of the bin and do an autopsy - but conscious enough of potential hazards to not bother re using them though.   Plenty replacements to hand, I just assembled another battery pack - but that seems to answer my question; what happened.

mike <ham789@netzero.net>: Nov 15 03:21PM -0800 On 11/15/2017 10:00 AM, Jeff Liebermann wrote: > that a tiny magnet will stick to the positive terminal and provide a > suitable button top contact (and test lead connection): > <https://www.ebay.com/itm/New-15pcs-Battery-Magnet-Spacer-Convert-Flat-to-Button-Top-All-Lithium-ion-/282548150944>   Or you can get the ones not specified as battery extenders https://www.ebay.com/itm/N35Super-Strong-Round-Disc-10x1mm-10x2mm-Magnets-Rare-Earth-Neodymium-N35/361874792648?hash=item54416b20c8:m:mVwQlu9k6vO_i4k0pOrvRVw for 3-cents each in hundreds.   If you get some square magnets, you can wrap a piece of battery tab material around them. Leave some sticking out so you can solder a wire or put a clip on it. Works for charging all types of batteries with magnet-attractive connection points. And the current doesn't go through the magnet or depend on the surface plating.

mike <ham789@netzero.net>: Nov 15 04:00PM -0800 On 11/15/2017 10:44 AM, Ian Field wrote:   > A shunt regulator failing short circuit (the most likely fault) wouldn't > do the battery any good at all - A SB diode in the feed makes that > accident unlikely.   I wouldn't put a lot of faith in the assumption that your regulator won't fail open. I suggest that a bad solder joint might be more likely than an actual component failure.   The diode also solves the problem of disconnecting the power source while the battery is connected.   But it adds another failure mode. A shorted diode will cause the battery voltage to exceed the safe max voltage. I'd also worry about the forward voltage vs forward current curve for the exact diode you're using. Depending on the charging current and the capability of your diode heat sink, the junction temperature might get well above ambient and need to be considered. A diode conducts all the way to zero volts. It's easy to assume that the current is small enough to be ignored, but VERIFY that's the case in your application. Look at the curves for your diode over temperature. What's the maximum battery voltage if you left it on charge for a week.   If you want to charge it as quickly as possible to the highest capacity, typically 4.2V depending on chemistry, you might find that it's not possible to do safely with a diode inline. Backing the max voltage off 200mV to be safer seriously impacts run time, but it's probably a good idea.   Another alternative is to set your shunt regulator to 4.2V and put a resistor across the diode. You get quickly to 3.9V or so. Takes longer for full charge but can be much safer.   Lithium batteries are usually charged right up near the destruction limit. There isn't much margin for error. If you have a limited supply of paranoia, charging lithium batteries is a good place to allocate some.

bitrex <bitrex@de.lete.earthlink.net>: Nov 15 01:10PM -0500 On 11/15/2017 02:12 AM, Rheilly Phoull wrote: > On 15/11/2017 2:00 PM, cashreserveflow128@gmail.com wrote: >> I have the jacks but it still don't, come on   > classic google groups grammar     Classic game popular in my grammar school days:   <https://www.youtube.com/watch?v=XJ5HAtVjfuw>

"pfjw@aol.com" <pfjw@aol.com>: Nov 15 11:00AM -0800 On Wednesday, November 15, 2017 at 1:10:46 PM UTC-5, bitrex wrote:   > > classic google groups grammar   > Classic game popular in my grammar school days:   > <https://www.youtube.com/watch?v=XJ5HAtVjfuw>   Back in ancient times, guys played Marbles or spun tops. Girls played Jacks. Few guys left the house without a shooter, a couple of cats'eyes and a top.   Peter Wieck Melrose Park, PA

Rheilly Phoull <froggins@iinet.net.au>: Nov 16 06:34AM +0800 > Back in ancient times, guys played Marbles or spun tops. Girls played Jacks. Few guys left the house without a shooter, a couple of cats'eyes and a top.   > Peter Wieck > Melrose Park, PA   Used to be "conkers" in the UK

carey_1959@yahoo.com: Nov 15 09:53AM -0800 Greetings-   I have an HK 680i from the 80s on which the volume cuts out. When I first turn it on there is sometimes sound output, but after several seconds it goes silent. If I turn the volume way up the sound will come back, but at ear-splitting levels; when I turn it lower, it goes silent again. I'm wondering if there are any simple ideas I might try? I have a can of Deoxit D5 and a bit of patience.   TIA.

"pfjw@aol.com" <pfjw@aol.com>: Nov 15 10:18AM -0800 A few quick questions:   Is/are there relays involved? And do they 'click' when this problem occurs? Are there any other symptoms?   Yes. Clean all controls and switches. Yes. Look for loose boards and loose connectors and looms from board-to-board. With the top off, and with a wooden stick such as a chop-stick or drum-stick, poke and prod (gently) here and there - systematically - from one end to the other to see if you can induce the symptoms. Pay special attention to the outputs.   I would also look for swollen, burnt, or leaky electrolytic capacitors, evidence of burnt parts or other visible symptoms. If there are relays, those would be the first thing I tapped.   This does, superficially, appear to be a mechanical issue and/or a power-supply issue if the relays are not receiving enough current to latch (not uncommon).   Good luck with it!   Peter Wieck Melrose Park, PA

dansabrservices@yahoo.com: Nov 15 10:27AM -0800 I would suspect the relays. Although the problem is not likely to be whether or not they are engaging. The contacts themselves within the relays are corroded. If you can't get to the contacts, replace the relay.   Another quick test is to turn up the volume. If the sound kicks in, the relay contacts are the problem.   Dan

"pfjw@aol.com" <pfjw@aol.com>: Nov 15 10:52AM -0800 > I would suspect the relays.   Yep. Should have mentioned this as well! Thank you!   And, I have been known to remove the plastic caps and clean the contacts. Whereas most of these relays are still available, it can me a major PITA to replace them if a large board needs to come up to get to the bottom.   Peter Wieck Melrose Park, PA

dplatt@coop.radagast.org (Dave Platt): Nov 15 11:07AM -0800 >If I turn the volume way up the sound will come back, but at ear-splitting levels; when I turn it lower, it goes silent again. I'm >wondering if there are >any simple ideas I might try? I have a can of Deoxit D5 and a bit of patience.   Possible problems:   - Bad volume-control pot. It might be very dirty (in which case, rinsing it out with DeOxIt might fix the problem) or the conductive element might be work or cracked (in which case, replacing the pot is the only good solution).   - Bad speaker-protection relay - the contacts may be "burned" or dirty. These can sometimes be cleaned, or the contacts burnished with a proper tool (usually a very-fine-grit diamond polisher) but must sometimes be replaced. [From what I see of the schematic, your HK doesn't have one of these, so you can skip this.]   - A dirty or bad signal-selector switch... either the input selector, or the "tape monitor" switch, tone control switch, tone defeat switch, speaker on/off switch, etc.. Cleaning all of these with DeOxIt or similar may fix the problem.   - A cracked solder joint somewhere on the PC board.   - A bad board-to-board or board-to-cable connection. It looks as if that HK has a bunch of interconnect cables between the boards... a loose plug connection (e.g. from metal fatigue in the socket) or oxidation might cause problems.   - An inter-stage coupling capacitor (typically electrolytic) which has gone bad... they sometimes become leaky and can also fail intermittently.   Before you actually start trying to fix things, you should do some trouble-shooting to identify the specific section of the receiver that's not working right. A good place to start is at the tape-monitor jacks. If you tune to a known-good FM station, select FM as your input, and can see a signal at both "out to tape recorder" jacks, you can deduce that the input half of the receiver is likely OK and that the problem lies "downstream" (control section and amplifier). Conversely, if you can feed another receiver's "to tape recorder" outputs into the HK's "tape monitor" input, then select the "tape monitor" function, and get reliable and controllable output from the speakers, you'd know that the control section and amp are probably OK and that the problem lies "upstream" (in the input selection section).   One useful diagnostic technique: set it up to (try to) play a known-good signal at a moderate volume level into a set of test speakers (i.e. ones you don't care about). Then, start tapping on things - the board, controls, cables, jacks, switches, etc. - with a wooden chopstick. If there's a cracked or intermittent connection, it will probably make itself obvious when you tap on or near its location.

carey_1959@yahoo.com: Nov 15 11:28AM -0800 Thanks very much to you all for this wealth of advice. I need to read and digest it all before I do anything else, since I am *not* a tech guy.   Again, thanks, and I'll post again when I understand more.

Jeff Liebermann <jeffl@cruzio.com>: Nov 15 09:37AM -0800 On Wed, 15 Nov 2017 07:22:29 -0000 (UTC), Blake Snyder >> become too busy, which means an external device or independent >> "heartbeat" timer.   >Klugey approach?   It's spelled kludge. In the not so distant past, I helped maintain a series of mountain top weather stations. Service calls were expensive and best avoided. As an added bonus, this was in an environment full of RF pollution.   >Set a WatchDog Timer reboot.   Sure, if the watchdog timer is independent of what it's monitoring. Long ago Kantronics KPC-2 TNC (packet radio modem) had a built in watchdog timer. Too bad it was all software and located in the same chip it was monitoring. When the KPC-2 hung, the watchdog timer also hung. In later models, they simply removed the watchdog timer.   Roll forward a few years, and I'm maintaining servers in a big server farm. Remote reboot via ethernet was problematic. It was quite common to arrive at the ISP and find a message declaring that the OS refuses to reboot until some obscure process agrees to die gracefully. The customer got tired of paying me to reboot his servers, and I got tried of driving 50 miles to flip a switch. So, I install a paging receiver and decoder to initiate a reboot. That was quite a challenge as server farms are full of RF interference.   However, even that didn't quite work. It seems that most servers have a "feature" called WOL (Wake on LAN) that allows me to remotely power on the server. In order to do that, it needs to have the power left on to the LAN card(s) even when the server is turned off. (Note: WOL is mostly used for desktops, but at the time was also appearing in servers). Sometimes, the ethernet card would hang. If I reboot the machine, the LAN card would remain hung. If I flipped the power on/off switch on the server, it still would remain hung. Of course, with no connectivity, I couldn't do a remote reboot in software. Compaq later introduced a server management card that provided a secondary management channel, but it was too expensive. The only good solution was to pull the plug on the server.   For server farms, I eventually went to SNMP managed remote power switches. I still have a bunch of APC AP9211 switches in service. <https://www.google.com/search?q=apc+ap9211&tbm=isch> Primary control is via ethernet, but some had a secondary control channel via the serial port.   I've tried other schemes and solutions. Some worked, but all had a surprise hidden somewhere.   >Specify an IP that won't respond to pings, set up the WatchDog timer to >ping it every 24*60*60 seconds, with a fail count of 7. (or suitable >numbers that the GUI will accept).   Won't work and may I humbly suggest that you think about this a bit more. The problem is that in any ISO layer cake device, it is possible to have the lower layers working, while the upper layers are hung or stuck in a spin look making the lower layers too busy to respond. I've seen machines that respond quite nicely to ICMP pings where the main function (email or web server) is totally hung. For these things, you need to test the higher level services and not rely on the lower levels.   In this situation, there's one big advantage that MIGHT make such a simple ping work with a wireless link. All wireless connectivity is done at layer 2 (MAC layer). The IP layer is only involved in managing the device. If one pings by IP address, it's fairly good assumption that the underlying layers are working. Some services such as SNMP, SMTP for email fault notification, and the usual internal web server might be hung, but with layer 2 still working, the wireless bridge would likely still be doing its job.   Now, back to the original problem. Heartbeat timers and timed reboots are a kludge. They're needed because the manufacturer of the wireless bridge radios didn't do a decent job of keeping his hardware up and running 24x7. The failure might be in software, susceptibility to power glitches, susceptibility to DoS attacks, crappy components, or environmental issues (overheating). If the wireless is bridge is so unreliable that it has to be rebooted once per week, I suggest you look into the cause of this unreliability, and not apply a band-aid.     -- 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

rickman <gnuarm@gmail.com>: Nov 15 12:21PM -0500 Michael A Terrell wrote on 11/15/2017 11:17 AM: >>> sufferer fools of any kind, in yet another newsgroup.   >> Must be rough looking in the mirror... I'm just sayin'   > No one cares about your ignorant blather, as well.   Obviously you do or you wouldn't have replied... I'm just sayin'   --   Rick C   Viewed the eclipse at Wintercrest Farms, on the centerline of totality since 1998

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