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Phil Allison <pallison49@gmail.com>: Mar 08 04:06PM -0800 David Farber wrote:     > That microphone is not at all physically similar to the one that I am > servicing.   ** It should be very similar.   Are you SURE it is a Shure mic ??   The Chinese have been making copies of Shure mics and radio mics.   > I told the user it wasn't worth fixing. You can buy a new one, > though not a Shure model, for under $100.   ** Fine, if all you want is a piece of garbage.     .... Phil

"David Farber" <farberbear.unspam@aol.com>: Mar 08 10:52PM -0800 Phil Allison wrote: >> though not a Shure model, for under $100.   > ** Fine, if all you want is a piece of garbage.   > .... Phil   Am I SURE it's a Shure mic?? Excellent question. It says Shure and it's spelled correctly. The thing that doesn't make sense to me is that when you unscrew the top cover, the microphone remains in place and there doesn't seem to be an easy way to remove the microphone capsule from the rest of the unit. I had to force off the bottom part of the mic handle to get to the circuit board. Inside I found that the tab that extends from the mute switch was broken. (I know you said the switches are delicate but I could not find any other way of opening the case and even before I opened the case it appeared the mute switch wasn't working properly.) I did not find any physical damage to the board. When I tried to reinstall the circuit board into the handle, it took a lot of pushing. Is there an easy way to determine if this is a knockoff?   Thanks for your reply. -- David Farber Los Osos, CA

"David Farber" <farberbear.unspam@aol.com>: Mar 08 10:56PM -0800 > but you should see some effect of the mic onto the snow. That will > tell you if it is putting out RF or not. > m   I do have an old Sony set which I still watch every day. I'll give it a try tomorrow and let you know what happens.   Thanks for your reply. --   David Farber Los Osos, CA

Phil Allison <pallison49@gmail.com>: Mar 08 11:28PM -0800 David Farber wrote:   > > ** Fine, if all you want is a piece of garbage.   > Am I SURE it's a Shure mic?? Excellent question.   ** Pun fully intended.     > It says Shure and it's spelled correctly.     ** Very comforting.     > physical damage to the board. When I tried to reinstall the circuit board > into the handle, it took a lot of pushing. Is there an easy way to determine > if this is a knockoff?   ** I was sent a Shure fake model a couple of years ago, the Chinese had copied the handbook, the brochure, the plastic case in every detail - except the electronics.   The Rx had two antennas, but only one was connected to anything inside.   The capsule was nothing like an SM58 and the performance was bloody awful. The BIGGEST clue was that it was purchased from Honk Kong for an absurdly low price. AFAIK, genuine Shure product is never sold that way.   There are a bunch of Chinese SM58 knock-offs too, some worse than others, none worth buying - mainly cos none of them last for decades the way the famous mic is famous for.     .... Phil

Jasen Betts <jasen@xnet.co.nz>: Mar 08 06:53PM > I ordered one from Newark, and plan to use it > on my messed-up switching power-supply designs. > Qualitative results will be fine.   a few years back there was talk of using a video head from a VCR (after removing it from the drum) to probe AC currents. It should be good to a few megahertz. a core from an ethernet transformer with a gap added could be another option. a spool-shaped inductor would probably work too.     -- This email has not been checked by half-arsed antivirus software

John Larkin <jjlarkinxyxy@highlandtechnology.com>: Mar 08 04:05PM -0800 >to a few megahertz. a core from an ethernet transformer with a gap >added could be another option. a spool-shaped inductor would >probably work too.   A little unshielded drum-core inductor is a handy h-field probe.     --   John Larkin Highland Technology, Inc picosecond timing precision measurement   jlarkin att highlandtechnology dott com http://www.highlandtechnology.com

jurb6006@gmail.com: Mar 08 10:58PM -0800 On Tuesday, March 7, 2017 at 1:21:14 PM UTC-5, Cursitor Doom wrote:   > > Or maybe they just like > > coming to San Francisco.   > Unlikely. ;->   Maybe they could not find any flowers :   https://www.youtube.com/watch?v=bch1_Ep5M1s   Sorry I did not get the studio version, but this one looks interesting.   But I hate to say it, you will never catch me dead anywhere in California. Maybe fifty years ago but not today, even if I could afford the rents there.

isw <isw@witzend.com>: Mar 08 08:55PM -0800 In article <o9of0e$bi6$1@dont-email.me>, N_Cook <diverse@tcp.co.uk> wrote:   > version ran with noticably hotter heatsink and cooler devices. > IIRC the datasheets quote an (fraudulent?) impossible degree of > squashing of pads, not obtainable with one screw thru a tab.   If your claim is that the mica version "ran with noticably hotter heatsink and cooler devices", then something went wrong with your measuring technique. It's a sort of requirement that heat flows from warmer to cooler, and so the devices necessarily must be warmer than the heatsink, no matter what (passive) material you use in the interface.   A better-performing thermal interface would be one which *minimized* the difference in temperature between the device and the heatsink.   Also from your description, it sounds like you were measuring the performance of a specific mounting method, rather than the thermal resistivity of one of its components.   Isaac

isw <isw@witzend.com>: Mar 08 08:57PM -0800 In article <7eade150-116b-41af-a4f3-230e1e10d3f8@googlegroups.com>, > semiconductors you can get at a sensible price AND will easily handle 200V or > more. Just a smear of white, silicone grease on each side and you are there.   > The reason makers ever use silicone pads is saving assembly time.   Sometimes, pads are used to increase spacing and minimize device-to-ground capacitance.   Isaac

Phil Allison <pallison49@gmail.com>: Mar 08 09:24PM -0800 isw wrote:       > measuring technique. It's a sort of requirement that heat flows from > warmer to cooler, and so the devices necessarily must be warmer than the > heatsink, no matter what (passive) material you use in the interface.   ** You must be illiterate.   The OP did not say the devices were cooler than the heatsink.       > A better-performing thermal interface would be one which *minimized* the > difference in temperature between the device and the heatsink.   ** Which is consistent with the OP's finding.     > Also from your description, it sounds like you were measuring the > performance of a specific mounting method, rather than the thermal > resistivity of one of its components.   ** Hogwash.   Try learning to read.     .... Phil

Phil Allison <pallison49@gmail.com>: Mar 08 09:54PM -0800 isw wrote:       > > The reason makers ever use silicone pads is saving assembly time.   > Sometimes, pads are used to increase spacing and minimize > device-to-ground capacitance.   ** Never matters with audio amps, SMPS or the like.   With frequencies above a few MHz, alumina pads are a far better choice, allowing thickness of a few mm with good conductivity.       .... Phil

jurb6006@gmail.com: Mar 08 10:16PM -0800 >"** Thin mica (0.05mm) is still the best performing insulator material for semiconductors you can get at a sensible price AND will easily handle 200V or more. Just a smear of white, silicone grease on each side and you are there. "   Actually it should not be smeared. Just a dab will do you, and when the force is applied whether by screw or other means it is better because there are no air pockets in it.   >"If the power per device is high (ie over 20 watts) then forget silicone pads. "   Well my Phase Linear 400-2 seems to get along with them quite well. However they might be thicker or something, I never check. If I recall correctly they say not to reuse them, like when you change the transistors to get new insulators, but I did it and it works fine.   >"Forget published specs too, pad makers lie. "   They all lie. You are probably old enough to remember when we could trust big companies. Banks even. Now, at least in the US you cannot trust any of them. Even the water company. Recently those new water meters screwed up and overcharged the living shit out of a bunch of people. YOU HAVE TO PAY THAT OR LOSE YOUR HOUSE. Then later you can fight back for a refund. Of course that might be hard to do when you are homeless. That is how it is here dude, and I got alot more. Seriously, banks on the phone told people to stop paying their house payments to qualify for a refi and then swooped down and foreclosed.   In the US you have to be very careful about making automatic payment because they will use a big fat ten inch to do your colonoscopy. It might be different where you are, but here you cannot even trust the phone or cable company. Or the gas company. They are a bunch of crooks and are only stopped bby the chance of getting caught, or worse, screwing someone who can get media coverage about it.   Due to this, I prefer to just write checks. Plus, if you want to pay by phone they charge you ! And then, instead of going into the bank and dealing with a teller who is PAID they charge you to go to the ATM. They have been in place for a damn long time and should be paid off by now, but they keep on charging, as if they are still amortising the cost. They are a bunch of thieves. You cannot trust anyone, at least here. You might have better laws there but here it is open season on us. And it is looking like Trump is not going to do shit about it. He has been somewhat disappointing.   The one good thing about the state of affairs in the US is that I am old enough not to give a shit anymore.

jurb6006@gmail.com: Mar 08 10:39PM -0800 >"** Which is consistent with the OP's finding."   If I am understanding this correctly, this is the reason that amps now have floating transformer secondaries and have eliminated the insulators.   Seems like it was not so big an issue in the old days, but now they are fan cooled and they DO depend on the temperature difference to keep from frying out.   And mounting methods ? Jesus H Christ, taking apart this shit now is ridiculous. You got one bad pair of output, the whole damn board has to come out and then all of the outputs have to be dismounted. This is one of the reasons I quit. I am to the point where I do not want to work on anything not old enough to drink. I mean it, and these MFs with their glue, I want to go in that factory with weapons of mass destruction and remove all glue. I do realise why they do it, but damn. The way they do it they might as well just glue the lid on and call it a toaster.   And even supposedly better amps are built in a pan. There is no bottom access. In many you can't even get the board out without the heatsink on which makes for a very awkward situation, and running it without the heatsink is a big nono.   Shit like this is why I am pretty much retired and just selling off my equipment. Perhaps I am inferior on that respect, but I also have physical problems that make it very difficult. But manufacturers do not think much of service, all they want to do is sell and have the product in the customer's hand, working. After that they pretty much do not give a shit.

Phil Allison <pallison49@gmail.com>: Mar 08 10:47PM -0800 > >handle 200V or more. Just a smear of white, silicone grease on each > >side and you are there. "   > Actually it should not be smeared.   ** Smear = thin layer applied to each side.   > Just a dab will do you,     ** It's not bloody Brylcreem !!!   > >"If the power per device is high (ie over 20 watts) then forget > > silicone pads. "   > Well my Phase Linear 400-2 seems to get along with them quite well.   ** Yawnnnnn.....   Use that amp in a PA system and it will blow up.   I have a PL400 mk2 here, with all the pink pads replaced with mica.   The TO3 devices run about 25 degrees cooler because of the change.       > >"Forget published specs too, pad makers lie. "   > They all lie.   ** Not all.   The big lies are from makers of sil pads and TO220 high current mosfets. Oh, and loudspeaker makers with fake power handling specs.         .... Phil

frank <frank@invalid.net>: Mar 08 05:53PM Hello folks,   did anyone suceeded in repairing traces on that old plastic sheet printed circuits keyboards? Some traces are interrupted and it's impossible to solder on that kind of plastic/trace combination. I've had some success on plastic substrate when the tracks were copper strips of sufficient thickness, but in this case they looks like black conductive material and the plastic substrate is so thin that any tip at a useful temperature for soldering instantly makes a hole. I've been thinking about conductive glue, but it might not stick or make a good contact. So if anyone already had experience (positive or negative) is very welcome. It's a 30 years old mitsumy custom keyboard, so not replaceable with something modern. Thanks Frank

ohger1s@gmail.com: Mar 08 11:03AM -0800 On Wednesday, March 8, 2017 at 12:56:22 PM UTC-5, frank wrote: > modern. > Thanks > Frank   Get a Circuit Writer pen from Caig labs. I've tried using black conductive paint from several sources and it's not conductive enough.

Look165 <look165@numericable.fr>: Mar 08 08:17PM +0100 Try this :   https://www.chemtronics.com/c-275-circuitworks-conductive-pens-and-inks.aspx.   It is magic.   frank a écrit :

"pfjw@aol.com" <pfjw@aol.com>: Mar 08 11:42AM -0800 At +/- $12.50 per pen, it is going to be cheaper than a new board in very nearly every case.   Peter Wieck Melrose Park, PA

N_Cook <diverse@tcp.co.uk>: Mar 08 07:47PM On 08/03/2017 17:53, frank wrote: > modern. > Thanks > Frank   I've used "Tempest-proof" RFI blocking, nickel spray . After shaking the aerosol can , squirt some into a small container and paint on with a toothpick, good low ohmage

"pfjw@aol.com" <pfjw@aol.com>: Mar 08 12:43PM -0800 On Wednesday, March 8, 2017 at 2:47:19 PM UTC-5, N_Cook wrote:   > I've used "Tempest-proof" RFI blocking, nickel spray . > After shaking the aerosol can , squirt some into a small container and > paint on with a toothpick, good low ohmage.   True, but nickel is very hard to solder. Silver is not. The former when soldering is necessary, the latter when not.   Peter Wieck Melrose Park, PA

"Benderthe.evilrobot" <Benderthe.evilrobot@virginmedia.com>: Mar 08 08:28PM "Jon Elson" <jmelson@wustl.edu> wrote in message news:f6SdnUJ1WK5gbiDFnZ2dnUU7-VnNnZ2d@giganews.com... > source. > It wants to make SURE the files on the stick are safe before removing the > old ones. That makes good sense!   Near as I can tell; its a file size issue - and probably the NTFS USB stick causing the mischief.

"Benderthe.evilrobot" <Benderthe.evilrobot@virginmedia.com>: Mar 08 08:31PM "Baron" <baron@linuxmaniac.net> wrote in message news:o9pbtc$dl1$1@dont-email.me... > because some address was different or wrong. Off by one was a > popular mistake. You soon became very familiar with PC hardware in > those days.   Must've been before I first tried Linux.   Despite being a late convert from M$ command line - I found Linux command line to be too much PITA.

"Benderthe.evilrobot" <Benderthe.evilrobot@virginmedia.com>: Mar 08 08:32PM <makolber@yahoo.com> wrote in message news:41ec0693-e90a-4944-9fdb-14f452672922@googlegroups.com... > Do not use a long extension wire for the USB.   > mark   WTF?!!!

N_Cook <diverse@tcp.co.uk>: Mar 08 07:40PM On 08/03/2017 16:04, N_Cook wrote: > not. Any pics I've found is ambiguous as the degree of left and right > throws on the white keys, let alone the unseen pivot slot widths that vary. > C D E F G A B C is not very helpful   Looking at an old Casio keyboard, for white keys the direction of throws at the leading edge is, per octave CDEFGAB right,double equal,left,right, double biased R, double biased L, L   The Roland moulding number sequence of each octave is EB2,CF1,D,EB2,CF1,G,A,EB2 top C is CF and black notes 23   Lay out the white keys , just laying on the top, mark the pivots that take the black keys, remove the white keys, set all the black keys in , then all the white keys, finally set the springs on with a hook. holding the fixed static end with a finger to avoid the spring flying off

"Gareth Magennis" <soundserviceleeds@outlook.com>: Mar 08 07:48PM "N_Cook" wrote in message news:o9p9u4$61i$1@dont-email.me...   Before I got to this, an electrician had removed all the keys without some sort of sequence marking, so I ended up with a carrir bag of them. I assumed out there, via google bunging in roland keyboard keys, CF1,EB2,CF, D, A ,G , C ,23 someone would have put out there the sequence required to lay up a Roland keyboard moulded with those cryptic alphanumerics, but apparently not. Any pics I've found is ambiguous as the degree of left and right throws on the white keys, let alone the unseen pivot slot widths that vary. C D E F G A B C is not very helpful           ***************************************************************     I can't make head nor tail of the above, but putting keys back is not usually a problem.   Put all the black keys in first. White keys marked "CF" are both C and F keys, they are identical. Similarly "EB" keys are both E's and B's. D keys are "D". G keys are "G". A keys are "A".   Top C key is unique.         Gareth.

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