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David Lesher <wb8foz@panix.com>: Mar 09 04:41PM The Washington Post had some great photos of a house with every outlet and switch blown out of the walls.   Seems there was a FIOS installer trenching there when it happened. The WP didn't say, but from the imagery, I suspect they crossed the 34KV feed to the pictured pad-mount transformer with its 240/120 output.   It was news because Verizontal refused to pay; saying it was the contractor's fault not theirs.       -- A host is a host from coast to coast.................wb8foz@nrk.com & no one will talk to a host that's close.......................... Unless the host (that isn't close).........................pob 1433 is busy, hung or dead....................................20915-1433

"James Wilkinson Sword" <imvalid@somewear.com>: Mar 09 04:45PM > with its 240/120 output.   > It was news because Verizontal refused to pay; saying it > was the contractor's fault not theirs.   Which it was. But the contractor should have to pay, and Verizon has to pay in the interim, just as if you order something online and it's lost in the post, it's the postal company's fault, but you still claim from the seller, and the seller from the postal company.   -- My wife and I were watching Who Wants To Be A Millionaire while we were in bed. I turned to her and said, "Do you want to have sex?" "No," she answered. I then said, "Is that your final answer?" She didn't even look at me this time, simply saying, "Yes...." So I said, "Then I'd like to phone a friend." And that's when the fight started...

ohger1s@gmail.com: Mar 09 04:37AM -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.   In small transistors, I put a tiny dab right in the center of the transistor. On larger devices, I tend to spread it to cover at least half the heatsink. On hybrid modules I tend to give it a complete thin peanut butter coating.   I was taught that compound should be applied by a dot and let it spread out by the compression of the mounting technique to prevent an air pocket. What I've found out is that very few mounting methods compress the device sufficiently to spread and force most of the compound out.   You've done your share of STK replacements - how many did you remove to discover the compound was in the center but never spread towards the outer edges?   I use Dow Corning 340 which is a very dense and heavy compound, and this stuff takes a lot of force to compress it all the way across the back of a large heatsink.

Mike Paff <paffm@yahoo.com>: Mar 09 08:13AM -0800 >performance of a specific mounting method, rather than the thermal >resistivity of one of its components.   >Isaac   I think you are misunderstanding N_Cook's statement.   I read it to be that he ran two setups, one with a mica insulator, and one with a sillypad. The device using the mica insulator was cooler than the device using the sillypad, and the mica insulator device's heat sink was warmer than the sillypad device's heat sink. This implies that the mica insulator is more efficient at moving heat from a device to the heatsink than the sillypad.

oldschool@tubes.com: Mar 09 10:33AM -0600 On Mon, 6 Mar 2017 21:56:45 -0000, "Gareth Magennis"   >Cheers,   >Gareth.     Back in the 70s they used Mica insulators, and coated them with silicone grease to transfer heat. Unless the installer cracked them during installation, they probably last forever.   I suppose they now came up with some cheap crap substance to save a buck. If I ran across this, I'd change all of them with the old mica types before more stuff burns up.

oldschool@tubes.com: Mar 09 01:39AM -0600 40 years ago, back when I did a lot with electronics, capacitors were either F (farads), UF or MFD microfarads, (UF and MFD were the same thing), or PF (Picofarad). Now they are using NF. What the heck is that?   I just bought one of these digital meters that not only measure voltage, current and ohms, but also measures caps. I just grabbed some old paper/wax caps (because they were handy).   A .5 cap is reading .455 UF   but a .1 UF cap is reading 106.3 NF (why the heck does it not read in terms of UF?)   .01 cap is showing   .05 cap is showing 52.6 NF   .02 (ceramic cap) is reading 15.86 NF   40 UF electrolytic is reading 48.1 UF   I could go on, but the ones that are reading in terms of UF are close to right. (old caps so they are not real precise).   But those reading NF have my head spinning..... There is no means to change the settings to read UF instead of NF. I am completely lost and confused!!!   Unfortunately I do not have any PF caps that are not connected to a circuit, so I dont know if that would read PF or NF or UF.....   Seems we live in a time when everything that was once simple has become complicated and for no advantage. Kind of reminds me of trying to determine if I need a 1/2" or a 12 mm socket, when both look to be the same size.... More senseless complication....

MJC <gravity@mjcoon.plus.com>: Mar 09 09:35AM In article <mvv1cct7jqnr4kpf4lr8h6g91lu76olp1l@4ax.com>, oldschool@tubes.com says... > complicated and for no advantage. Kind of reminds me of trying to > determine if I need a 1/2" or a 12 mm socket, when both look to be the > same size.... More senseless complication....   Doesn't your head spin with feet, inches, furlongs, bushels, and so forth? To the extent that a probe can crash into Mars?   (I'm waiting to see whether the UK, where I live, starts to reverse its slow reluctant switch to metric measurements when it leaves the EU!)   Mike.

dansabrservices@yahoo.com: Mar 09 03:52AM -0800 > complicated and for no advantage. Kind of reminds me of trying to > determine if I need a 1/2" or a 12 mm socket, when both look to be the > same size.... More senseless complication....   1 mF (millifarad, one thousandth (10−3) of a farad) = 1000 μF = 1000000 nF 1 μF (microfarad, one millionth (10−6) of a farad) = 0.000 001 F = 1000 nF = 1000000 pF 1 nF (nanofarad, one billionth (10−9) of a farad) = 0.001 μF = 1000 pF 1 pF (picofarad, one trillionth (10−12) of a farad)   Dan

whit3rd <whit3rd@gmail.com>: Mar 09 03:53AM -0800 > 40 years ago, back when I did a lot with electronics, capacitors were > either F (farads), UF or MFD microfarads, (UF and MFD were the same > thing), or PF (Picofarad). Now they are using NF. What the heck is that?   It's Systeme Internationale (so, blame the French).   Standard metric prefixes for SI units include Greek letter mu (µ) often rendered with lowercase 'u', meaning micro, 10^-6. 'n' (has to be lowercase!) for 'nano', 10^-9. Cannot use the capital M like lowercase, 'MF' would mean mega-farads, and the 'MFD' would not look like ANY real unit of measurement.

Ralph Mowery <rmowery28146@earthlink.net>: Mar 09 10:05AM -0500 In article <mvv1cct7jqnr4kpf4lr8h6g91lu76olp1l@4ax.com>, oldschool@tubes.com says...   > 40 years ago, back when I did a lot with electronics, capacitors were > either F (farads), UF or MFD microfarads, (UF and MFD were the same > thing), or PF (Picofarad). Now they are using NF. What the heck is that?   Thought you were old school.   What is the PF stuff ??? For me it was usually uF and uuF for the small stuff and the MFD was for the larger capacitors.   I am not old enough to remember when most all capacitors were called condensers all the time. For me most electronics was capacitors and the condensers were used across the points of gas engines.   I think that NF stuff was (is) an attempt to get numbers to the left of the decimal point. While not exectally,but similar to the scientific notation where you have one number to the left of the decimal point and all the others to the right raised to a power of ten.

MJC <gravity@mjcoon.plus.com>: Mar 09 03:20PM In article <MPG.332b394e49149ff198988d@news.east.earthlink.net>, rmowery28146@earthlink.net says... were used across the points of gas engines. > the decimal point. While not exectally,but similar to the scientific > notation where you have one number to the left of the decimal point and > all the others to the right raised to a power of ten.   Yes, and definitely not rendered with no digit (not even a zero!) before the dot, as in OP's posting. It would be too easy to fail to notice the dot and get the measure very inaccurate!   Compare Fahrenheit, an attempt to avoid any negative temperatures. Soon rendered pointless by better refrigeration and experience of colder climates. There's now an absolute solution!   Mike.

oldschool@tubes.com: Mar 09 10:19AM -0600 On Thu, 9 Mar 2017 10:05:51 -0500, Ralph Mowery >the decimal point. While not exectally,but similar to the scientific >notation where you have one number to the left of the decimal point and >all the others to the right raised to a power of ten.   Those PF caps were also known as MMFD or as you said, UUFD (usually in lower case). And yes, electrolytics were usually labelled as MFD, rather than UF. NF was never used back then, I never even heard of it.   However I am finally making sense of it, even though it's sort of annoying having to change stuff that I know all too well. But I did finally figure out that to convert to UF from NF, just move the decimal point 3 places to the left. Thus a 50 nf cap is a .05uf cap. Which in my measurements showed the .05uf cap that I measured as 52.6nf. Pretty darn accurate for a 50 year old paper/wax cap. So, that cap would actually be a 52.6nf.   So, I now see it's not all that hard to convert, but being someone who hates mathematics and has always had trouble with math, it's just more tedious. I did find a few websites that have conversion charts, that show all common caps in UF - NF and PF. I saved the webpage since I am not always able to go online. I was hoping to find it in PDF format, or better yet a converter that could be downloaded and run right on my own computer without having to go online. But at least I have the saved webpage in my Electronics folder, which contains everything from PDF tube manuals, resistor/cap color code charts, common transistor and diode numbers, tube socket pinouts, wire gauge amperages, power conversion charts, and lots more.... In the old days I had books for all this stuff, now I got my desktop computer, and an identical copy of that folder on my laptop computer for portable use.   (Of course I do still have many of the old books too, but the computer is easier to use and takes up less space in my shop).

Johann Klammer <klammerj@NOSPAM.a1.net>: Mar 09 04:21PM +0100 On 03/08/2017 09:28 PM, Benderthe.evilrobot wrote: >> 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. did you unmount the usb stick manually as root, or sync, so the stuff got actually written out?   They had an issue once when the files got damaged when you just unplugged the stick. It was related to how their drive cache works. Maybe no one ever figured out how to fix it. They do tend to add layers of script and candy to obfuscate those issues.   check dmesg for kernel warnings/errors (not the file, type dmesg on the bash prompt)

bruce2bowser@gmail.com: Mar 09 04:23AM -0800 -- https://m.youtube.com/watch?v=bqRL4Znh8Xs   (16 minute clip onward)

jurb6006@gmail.com: Mar 09 01:51AM -0800 >"Having a plate connection on top of a tube instead helps a lot. "   It sure did with HOPs (LOPT for you all across the pond)   But IIRC in the beginning they used that top connector for the grid. Seems that later they figured out a better way.

ohger1s@gmail.com: Mar 09 04:16AM -0800 > >"Having a plate connection on top of a tube instead helps a lot. "   > It sure did with HOPs (LOPT for you all across the pond)   > But IIRC in the beginning they used that top connector for the grid. Seems that later they figured out a better way.   LOL! I remember when I was just getting started in TV repair and my dad had a 40s radio in the shop for repair. In horror, I saw him put his finger on the "plate" cap of the IF tubes as a poor man's signal tracer. Of course, my first experience with a true plate cap was my finger on a horizontal output tube..

jurb6006@gmail.com: Mar 09 01:15AM -0800 >"Ages ago I bought the Mishibishi HS-M55 to be used for taping music only, at half speed. I was extremely pleased with the high quality machine."   Half speed is a bit of a mystery. The VCRs sold here had three speeds, SP, SLP and EP. But your question is more about the mechanism. Being where you are you are proabaly not on the NTSC system used in the US, it is much more likely you are on the PAL system. The only real functional difference is the color decoding and the rotary head speed is like 1,500 instead of 1,800.   When you talk about a hifi VCR you are talking about an AFM hifi system, which inherently has zero wow and flutter.   On V HS this was accomplished with an extra set of heads, which beta did not need. They had better bandwidth and could handle it.If your unit is on PAL it has a slower head to tape speed.   But your question is really about the mechanism and that should be about the same as what was sold here in the US. If so there are alot more things to go wrong than just belts.. I did many of them that required a serious teardown to replace some components down underneath. I made good fucking money doing that because not many people can.   If it is actually the same mech, there is a clutch asenbly underneath that is unbobtainium. There is no reason for the mu7ch to be different in another country. To have PAL instead is just a matter o the board, not the mech.   There are companies out the which will sell you belts of any dimensions. The question becomes, will they ship to you ?

Bruce Esquibel <bje@ripco.com>: Mar 09 10:44AM > than the HS-M55 but designed with rods instead of rubber belts ? I do > realize that the whole VHS concept is way out-of-date, only that I have > 40-odd tapes filled with good music, 300+ hours.     Can you try to explain what "rods" are?   If you are complaining about belts, I'd figure you mean you are looking for machines using direct drive, but for VHS, there were very few of those and generally didn't work well.   And "half speed" is the EP or "6 hour mode"?   I know some japanese machines (like JVC) didn't have the 4hr mode, just SP (2 hour) and EP (6 hour) but not sure how you get half using those two figures.   -bruce bje@ripco.com

N_Cook <diverse@tcp.co.uk>: Mar 09 09:09AM On 08/03/2017 19:48, Gareth Magennis wrote:   > Gareth.   I've only ever had to repair an odd broken key or 2. The sort of job where you could do with an apprentice. Show him how to fix one key and let him get on with the rest. What we were given 5 fingers on each hand for. One finger to hold the spring against the frame, so it doesn't fly off, one finger to hold the key back against the pivot and another finger to push the other loop of the spring over the spigot, while pulling the spring with a dental hook in the other hand , and then a satisfying clunk.

oldschool@tubes.com: Mar 09 01:58AM -0600 Regarding this kind of switch:   http://www.parts-express.com/data/default/images/catalog/240/060-908_HR_0.jpg   When it comes to working on old electronic gear from the 1950s thru 70s or 80s I keep reading the most common fault are the old paper/wax capacitors and electrolytics.   While there is truth to this in some cases, I have found a part that fails about 90% of the time on these old devices. They are these old slide switches (shown above). I just picked up an old Sencor Substitutor box from the 50s or 60s. The caps and resistors are not looking to be bad, but all three of the slide switches are junk. Even after sliding them back and forth 100 or more times, they are erratic at best, or dont work at all. (I am awaiting a can of Deoxit from an online order, since I can not buy it locally). I have my doubts that even this stuff will fix these switches.   Do they make more reliable replacements for this type of switch that will fit the same holes? Heck, even in the 70's when they were only a few years old, these switches were troublesome.   I never understood the reason for gold plated speaker terminals, but these switches should be gold plated, or something done to them, since they were always faulty.

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