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"William Sommerwerck" <grizzledgeezer@comcast.net>: Dec 14 07:37AM -0800 A few months back I got around to cleaning my condo's ceiling fixtures. These use tiny bulbs with miniature Edison bases. Some had burned out.   Some bulbs had behaved oddly, going "dead", but responding to being tightened. So I decided to examine all the non-lighting bulbs closely.   https://en.wikipedia.org/wiki/Edison_screw   All but one were burned out. The other showed no visible filament break, but my ohmeter said "open". I put it aside and tried periodically to fix it. (These lamps cost about a dollar apiece.) Though I unsoldered and resoldered the base and thread connections -- and confirmed there really were wires going to them -- there were no visible signs of damage.   This morning I gave one last shot. This time I twisted off the brass base, this action apparently pulling out the broken part of the wire going to the tip.   Using a magnifier, I could see that wire "ending" about halfway along the internal glass stem. It appears the wire had (or developed) a high-resistance section, which burned open the wire.   The same thing happened to the bottom Calrod unit in my oven several years back, so I shouldn't have been surprised.   PS: I have plenty of things to keep my busy, but I enjoy Show and Tell.

N_Cook <diverse@tcp.co.uk>: Dec 14 08:24AM The schamatic of this PV amp out there is for 2000, this 1994 version quite different. All the CC caps are small mustard colour epoxy covered small cylinders. Labelled with likes of 473 or 104 presumably for 47nF or 100nF but what about marks of 424 and 419?. Or are these the week/year date marks and the 3letter codes such as KNO and RSC are the value markings? 2 of these are physically broken, the wire ends broken at the solder slab. One labeled 473 measures 57nF and one marked 424 measures near enough 100nF. Vibration failure , inside Bandit 112 combo,preamp section with no stress telltales anywhere ?

Phil Allison <pallison49@gmail.com>: Dec 14 12:55AM -0800 N_Cook wrote:   > quite different. All the CC caps are small mustard colour epoxy covered > small cylinders. Labelled with likes of 473 or 104 presumably for 47nF > or 100nF   ** Sounds like AVX Spinguard ceramics.   Some of them are made with a high K ceramic (5ZU ) that has a horrible negative tempco and lousy tolerances.   Marshall used them in some versions of the Valvestate series - the negative tempco was so bad that you could hear the amp lose bass as it warmed up. Hit the PCB with some hot air and the effect was staggering.   Such caps are only good for supply bypass and ought never be found in any tone control or even stage coupling circuit.   Wrong markings probably indicates slack manufacture.   They appear to be no longer made.   My advice is to replace the lot.       ... Phil

N_Cook <diverse@tcp.co.uk>: Dec 14 03:09PM On 14/12/2014 08:24, N_Cook wrote: > slab. One labeled 473 measures 57nF and one marked 424 measures near > enough 100nF. Vibration failure , inside Bandit 112 combo,preamp section > with no stress telltales anywhere ?   Looking properly under x30 mag The 2 broken ones are marked R5I 473   and   KDQ 424

"David K. Bryant" <dbryant_94585@earthlink.net>: Dec 13 06:40PM -0800 On 12/08/2014 10:02 AM, David Farber wrote: > David K. Bryant wrote: >> The electromagnetic clutch on the end of the shaft.   > Is the clutch serviceable or is not worth the effort?   Certainly not worth the effort and possibly not even serviceable.   --- news://freenews.netfront.net/ - complaints: news@netfront.net ---

Ian Jackson <ianREMOVETHISjackson@g3ohx.demon.co.uk>: Dec 14 12:01AM In message <G6idnW0tRtnMkBbJnZ2dnUVZ7sOdnZ2d@bt.com>, Gareth Magennis <sound.service@btconnect.com> writes >> decomposed over time.   >Seems to work fine without it.   >(and I meant Double-Sided sticky tape)   I've got two LiteOn disk recorders - one an elderly LVW-5045, and a somewhat later version (similar number, but with something like GL on the end). With both have had the problems described.   With the older one, with the case cover off so I could see what I was doing - and with the drive fixing screws removed - I managed to get the front of the drive pulled forwards. Eventually I was able to detach the clip-on front of the drive (there's a knack to this) without causing damage, remove the drive completely, and separate the top and bottom covers. I then could see exactly where to drill a small hole front panel to poke in a straightened paper clip to operate the release mechanism. [Note that, these days, I make sure that I don't leave a DVD in the drive. However, even without a disk in the drive, it is usually reluctant to open if it hasn't been opened for a few days.]   With the later version, there is a drop-down flap on the front panel. I lowered this flap, and with my fingers crossed, I drilled in the panel behind a hole in the same place as the older recorder. With some persistence, I was then able eject a disk that had become glued in place on the 'double-sided sticky rubber' on the central capstan. So far, I haven't dismantled the machine to see what can be done to make the sticky rubber un-sticky.   -- Ian

"Gareth Magennis" <gareth.magennis@ntlworld.com>: Dec 14 01:28AM "Ian Jackson" wrote in message news:bPtGBuH2NNjUFwAI@g3ohx.demon.co.uk...   In message <G6idnW0tRtnMkBbJnZ2dnUVZ7sOdnZ2d@bt.com>, Gareth Magennis <sound.service@btconnect.com> writes >> decomposed over time.   >Seems to work fine without it.   >(and I meant Double-Sided sticky tape)   I've got two LiteOn disk recorders - one an elderly LVW-5045, and a somewhat later version (similar number, but with something like GL on the end). With both have had the problems described.   With the older one, with the case cover off so I could see what I was doing - and with the drive fixing screws removed - I managed to get the front of the drive pulled forwards. Eventually I was able to detach the clip-on front of the drive (there's a knack to this) without causing damage, remove the drive completely, and separate the top and bottom covers. I then could see exactly where to drill a small hole front panel to poke in a straightened paper clip to operate the release mechanism. [Note that, these days, I make sure that I don't leave a DVD in the drive. However, even without a disk in the drive, it is usually reluctant to open if it hasn't been opened for a few days.]   With the later version, there is a drop-down flap on the front panel. I lowered this flap, and with my fingers crossed, I drilled in the panel behind a hole in the same place as the older recorder. With some persistence, I was then able eject a disk that had become glued in place on the 'double-sided sticky rubber' on the central capstan. So far, I haven't dismantled the machine to see what can be done to make the sticky rubber un-sticky.   -- Ian         I removed all traces of the sticky rubber, it took some doing with a flat blade screwdriver and some potent solvents.   I don't know what it is doing there in the first place.       And yes, the mech had the capability to be teased open with a tool, had a hole been provided in the unit to do so.     Gareth.

Ralph Wade Phillips <news@philent.biz>: Dec 13 11:57AM -0600 One more possibility ...   Most switch mode power supplies (well, most back when I was doing active repairs!) use a "kick start" resistor to bleed some wall current AC into the switcher, so that it'll start the cycle.   This used to be the most common failure point IME for cheaper switch mode power supplies.   I'd check that also, if you don't find any bad caps.   RwP   -- I was sitting there, under my blanket, with fever and flu-like symptoms. I was fuzzy in the head and having a hard time concentrating. I had a horrible thought - "Is this what NORMAL feels like for average IQ people??"

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