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David Farber <farberbear.unspam@aol.com>: Jul 19 07:44PM -0700 On 7/18/2021 1:04 PM, Jeff Liebermann wrote: > If you have money to burn, Switchcraft is usually good: > <https://www.switchcraft.com/Category.aspx?Parent=42> > <https://www.switchcraft.com/Category.aspx?Parent=1253>   Hi Jeff,   Thanks for the links. I was able to solder the rivet to the tip and now the connection is solid. By the way, the cable is about 8mm in diameter.   -- David Farber Los Osos, CA

Rob <nomail@example.com>: Jul 20 01:47PM +0200 > -- > David Farber > Los Osos, CA   Jack-style plugs (no matter if 1/4" or 3.5mm) and solid, reliable connections are completly separate concepts. The only permanent solution is to use another type of plug.

David Farber <farberbear.unspam@aol.com>: Jul 20 07:33AM -0700 On 7/20/2021 4:47 AM, Rob wrote:   > Jack-style plugs (no matter if 1/4" or 3.5mm) and solid, reliable > connections are completly separate concepts. > The only permanent solution is to use another type of plug.   Point taken!   Thanks for your reply. -- David Farber Los Osos, CA

Jeff Liebermann <jeffl@cruzio.com>: Jul 20 09:30AM -0700 >Jack-style plugs (no matter if 1/4" or 3.5mm) and solid, reliable >connections are completly separate concepts. >The only permanent solution is to use another type of plug.   Good point, but not very useful. For example, I used to get about 50 XLR connector type microphone cables and extensions every year to repair from a local auditorium. About half failed because of failure to follow common sense soldering and assembly instructions. The other half were crude plastic clones of the real XLR connectors that simply fell apart. Also, some junk shielded microphone cable along with the usual creative wiring type errors: <https://en.wikipedia.org/wiki/XLR_connector> <https://www.google.com/search?q=xlr+connector&tbm=isch>   At the same time, I also got a few random speaker connector repairs using SpeakON connectors: <https://www.google.com/search?q=speakon+connectors&tbm=isch> <https://en.wikipedia.org/wiki/Speakon_connector> <<https://usa.yamaha.com/products/contents/proaudio/musicianspa/equipments/cable.html> Same problems as XLR. Bad soldering, bad assembly, and a failure to follow instructions. The problem for me with these speaker connectors is that I had to do the work on site instead of my former office. Another is where the speaker cables were installed without a service loop.   In other words, even the best connectors can be a problem.   Disorganized Drivel: 1. I'm mostly retired and don't do this kind of work any more. 2. I lost money on every cable I repaired. They take too long to repair. 3. The stage crew usually doesn't know how to solder or assemble connectors but pretends that they do. 4. AV Install Nightmares private group on Facebook. I'm not a member. <https://www.facebook.com/groups/133909986649315/> 5. Fixed wing aviation headset connectors use PJ-055 for the earphones and PJ-068 for the microphone. The PJ-055 is the same as the 1/4" connector under discussion. If there was anything inherently wrong with the design of these connectors, the aviation headset industry would have switched to something better long ago. <https://www.google.com/search?q=PJ-055&tbm=isch>   -- Jeff Liebermann jeffl@cruzio.com PO Box 272 http://www.LearnByDestroying.com Ben Lomond CA 95005-0272 Skype: JeffLiebermann AE6KS 831-336-2558

"Peter W." <peterwieck33@gmail.com>: Jul 19 09:49AM -0700 No need to know what else may be plugged into the circuit, as there is much else to consider first:   a) Given a 4.9A steady-state current draw at 115 VAC, that comes to 563 watts. Less than a standard hair-dryer (~1,200 watts). No big deal, even for a 15A conventional circuit (1,725 watts). Even one that shares a few other small things. b) Given that the typical surge for a conventional AC unit is very roughly eight (8) times the steady-state, the circuit must be able to withstand a very roughly 38 amp surge. This is well within the capacities of a standard 15A or 20A circuit breaker - AS LONG AS THERE ARE NO OTHER LOADS. *And as long as the breaker is functioning properly*. c) Most recent (modern) window units come with a GFI device mounted on the plug. So there should be no intrinsic danger of fire or overheating. d) Never, ever use an extension cord with a window AC unit. Ever.   With these in mind:   Plug them in, and let them rip. Should a circuit breaker blow, you will know what is shared. Remove those shared items and start over. If both units happen to be on the same circuit, use only one (1) at a time.   Ideally any AC line should be (at least) a dedicated 20A circuit using (at least) 12-gauge wire. Then there would be no discussion. If this is a rental, I feel her pain. If this is owned, install the dedicated circuits as-needed. They will not go to waste.   Peter Wieck Melrose Park, PA

Bennett <bjprice@cal.berkeley.edu>: Jul 19 11:41AM -0700 On 7/19/2021 9:49 AM, Peter W. wrote:   > Ideally any AC line should be (at least) a dedicated 20A circuit using (at least) 12-gauge wire. Then there would be no discussion. If this is a rental, I feel her pain. If this is owned, install the dedicated circuits as-needed. They will not go to waste.   > Peter Wieck > Melrose Park, PA   It's easy enough to determine if the 2 sockets are on the same circuit. Plug a lamp or radio into both, then flip circuit breakers. If both devices stop, they are on the same circuit.

Phil Allison <pallison49@gmail.com>: Jul 19 04:16PM -0700 Peter Wanker puked: =================   > a) Given a 4.9A steady-state current draw at 115 VAC, that comes to 563 watts. Less than a standard hair-dryer (~1,200 watts). No big deal, even for a 15A conventional circuit (1,725 watts). Even one that shares a few other small things. > b) Given that the typical surge for a conventional AC unit is very roughly eight (8) times the steady-state, the circuit must be able to withstand a very roughly 38 amp surge.   ** But increase to 76A if both units come on together. Current 16 times over nominal has a trip time of 0.1 seconds.   ( C type breaker)   ............ Phil

Rheilly Phoull <rheilly@bigslong.com>: Jul 20 08:30AM +0800 On 20/07/2021 12:14 am, bruce bowser wrote: >>> idea to have them both on the same circuit. >> Yup, and the ratings of the circuits etc.   > Including the distance covered by the wires? from the service's interface to the outlet?   Not really, the cable should be rated for the distance which in domestic situations is not great.

"Peter W." <peterwieck33@gmail.com>: Jul 20 03:47AM -0700 Result is exactly the same. If the breaker trips - reduce/eliminate the ancillary load(s). Nor can you read for content "AS LONG AS THERE ARE NO OTHER LOADS". In the USA, C-type breakers are used in specialty applications, generally not in a residential setting. Breakers here would be, typically, type A (plain), GFCI *breaker* (as compared to a GFI *device) and AFCI breakers. Within that group are many variants that describe how they are installed. Domestic breakers are available with a "high" current setting that will allow up to 20X rating for up to one (1) full second. They are expensive. I have used them several times to support wood shops and machine shops for 'heavy' hobbyists and wood workers. Never for 'regular' stuff.   Point being that nothing changes. Plug in the units - see if the breaker trips. If it does, adjust the load accordingly. And NEVER run both at the same time.   Learn to read.   Peter Wieck Melrose Park, PA

Phil Allison <pallison49@gmail.com>: Jul 20 04:05AM -0700 Peter W. wrote: ============ > Result is exactly the same. If the breaker trips - reduce/eliminate the ancillary load(s). > Nor can you read for content "AS LONG AS THERE ARE NO OTHER LOADS".   ** Irrelevant, my point did not need them.     > In the USA, C-type breakers are used in specialty applications,   ** Really? They the standard in every other place for GPOs.   > Domestic breakers are available with a "high" current setting that will allow up to 20X rating for up to one (1) full second.   ** Yep - that is similar to a D type.   Used where large ( or multiple) motor loads are expected.   > Point being that nothing changes. Plug in the units - see if the breaker trips. If it does, adjust the load accordingly. > And NEVER run both at the same time.   ** Yawwnnnnnnn ....   A pair of window units in two separate rooms are ** GONNA** be run on the same hot day or night !!!   You tedious fucking wanker.       ...... Phil

"Peter W." <peterwieck33@gmail.com>: Jul 20 04:09AM -0700 You always have a point. And, sadly, proper tonsorial attention is no longer an option for you.   Peter Wieck Melrose Park, PA

amdx <amdx@knology.net>: Jul 20 07:24AM -0500 On 7/19/2021 6:16 PM, Phil Allison wrote: > Current 16 times over nominal has a trip time of 0.1 seconds.   > ( C type breaker)   > ............ Phil     I had good luck with multiple freezers on one circuit breaker. I had twelve-25cuft freezers on 5 circuit breakers, over 15 years   I never had a a circuit breaker trip. I was always waiting for two freezers to start at the same time, but they never did.   I did have two freezers plugged into original house wiring, a bad connection developed at one outlet (35 years old),   this bad connection got hot enough to create an odor.   The odor came and when over a couple days before I isolated it to an outlet. When I took it apart the outlet crumble into pieces.   I was lucky to avoid a fire.                                     Mikek     -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

legg <legg@nospam.magma.ca>: Jul 20 09:29AM -0400 On Sun, 18 Jul 2021 15:32:09 -0700 (PDT), bruce bowser >> amps (115v), would overload any particular circuit. Without mapping the >> circuits, is there any way to know, other than plugging the unit in?   >What else is plugged into the circuit?   You can get an idea of what outlets are on the same branch circuit by fiddling with the fuse box an a sunny day.   Plug something noisy into the intended outlets and pull fuses till it stops.   RL

Stephen Wolstenholme <steve@easynn.com>: Jul 20 02:46PM +0100 >Plug something noisy into the intended outlets and pull fuses >till it stops.   >RL   A long time ago I had a house rewired. The fuses were clearly labeled. That has never happened since. If I was doing the job I would label the trips but I have retired.   Steve   -- http://www.npsnn.com

Jeff Layman <jmlayman@invalid.invalid>: Jul 19 06:26PM +0100 On 18/07/2021 21:15, Peter W. wrote:   > I have a very bad schematic from HiFi Engine that speaks to a shield. But its origin(s) and destination(s) are not clear.   > This condition is extant on both (2x) speakers.   > Any one out there who has had experience on these beasts? Any thoughts? If not, I will treat them as landfill and flog them as-is and with a very accurate description on the usual auction site, pick-up only. Otherwise, if there is hope, I am up for the work.   If you haven't already done so, is there any point in contacting Koss? I can't see them having any spares from that time with which they could charge an exorbitant repair fee, so maybe if they've got the service manual and/or circuit diagram, perhaps they'd let you have a copy.   --   Jeff

Phil Allison <pallison49@gmail.com>: Jul 19 05:41PM -0700 Peter Wanker is 100% NUTS !! =========================   > a) No blown fuses. Fuses are not new. > b) I have not yet plugged them in. I am generally resistant to plugging in a stranger until > I understand its functions and antecedents.   ** How bizarre !     > If I were to have a diagram of the potted transformers, I would be much more sanguine about applying power.   ** FFS why ???????     > c) I can isolate the potted transformers from the rest of the system. Theoretically, I could then determine if the amps are passing audio.     ** Really? What if the transformers are push pull output ?     > d) But I would REALLY like to know what is going on inside all that elephant snot....   ** Where - inside you fat head ?     ...... Phil

Phil Allison <pallison49@gmail.com>: Jul 19 05:44PM -0700 Peter Wanker hasLOST IT !!!   ==================     > Again: I do not understand clearly what is going on or should be going on.   ** Hmmmm - nothing new there ....     > And all I have is the nameplate in terms of anticipated current.   ** Then use that info.   > I am trying to get to where I can align the actual current to the anticipated current before I apply power.   ** Not even faintly possible .     ...... Phil

Jeff Liebermann <jeffl@cruzio.com>: Jul 19 11:15AM -0700 On Sun, 18 Jul 2021 16:30:55 -0700 (PDT), Jeroni Paul   >> caused by replacing the print cartridge while the printer power was >> turned on. Notice how close the contact pads are on the cartridge:   >The cartridge is supposed to be changed with the printer on, otherwise it is parked.   True. Opening the lid will move the cartridge carrier to roughly mid travel so that the cartridges are accessible: <https://support.hp.com/us-en/document/c03747637> I don't do it that way. What I've done to reduce failures is follow the instructions to the point where cartridges are accessible. Then, pull the power plug from the AC wall receptacle, or unplug the power cord at the printer. The cartridge carrier will remain accessible and not retract. Don't leave it like this for very long as the cartridge tend to drip ink in this position. When the internal power supply capacitors have discharged (about 15 seconds), I replace the cartridges and re-apply power. Once I convinced users to use this procedure, the number of printer failures were drastically reduced. However, failures didn't go to zero. My guess(tm) is that someone didn't follow my procedure and swapped cartridges with the power applied and then lied that they did it correctly.   >Output connections are supposed to be properly current limited and if this is really what happens maybe a diode or fuse resistor went open, may be repairable.   I've tried to troubleshoot to the component level on only one such printer and failed. The lack of a schematic, difficulty identifying some parts, and the need to build extension cables so the PCB is accessible were the major problems. I suspect that access to the factory diagnostic software would have helped, but I suspect it would simply say "replace the PCB". When I can buy a used and working replacement printer on eBay for about $50 total, there's not much incentive to repair the broken printer. <https://www.ebay.com/sch/i.html?_nkw=hp+envy+4500+printer> At my previous shop rate of $75/hr, break even with a replacement used printer is 40 minutes of labor (excluding parts cost). I could not do the repair in 40 minutes.   I don't know what killed 3 or 4 of these printers, but it keeps happening. I might have some luck identifying the culprit if I had a working printer next to the broken printer to use for comparison. That's a major project which will likely cost more than it's worth.   For what it's worth, my guess(tm) is that the outputs driving the piezoelectric heads is not properly protected. Something might be shoving power back into the driver IC, possibly when a cartridge is inserted at a slight angle causing the pads on the cartridge to short two adjacent pins together. I haven't spent any time investigating this theory beyond a quick inspection which showed that it was almost possible to short adjacent contacts. Measure the pad diameter on the cartridge. Measure the gap between adjacent pins on the carrier. In theory, there is sufficient clearance, but it's VERY close.       -- Jeff Liebermann jeffl@cruzio.com PO Box 272 http://www.LearnByDestroying.com Ben Lomond CA 95005-0272 Skype: JeffLiebermann AE6KS 831-336-2558

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