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Jeff Layman <JMLayman@invalid.invalid>: Dec 23 03:24PM A bit OT, as this is not one of the usual sophisticated repairs posted here.   SWMBO was not happy as the hand-held rechargeable vacuum cleaner was failing to switch on most of the time. It used a simple slide switch, but the motor worked barely once in a dozen attempts.   I dismantled it to find a simple slide switch - in the back "off" position the 10 NiMH batteries were connected to the charging circuit, and slid forward they were instead connected to the motor. A few squirts of WD40 failed to solve the intermittent operation, so I removed the switch to examine it.   And found my Christmas present! I usually find these Chinese imports are made to the cheapest spec possible, and expected to find a single-pole single toggle switch. But no, this was a /double/ pole single toggle switch, and the other pole was unused. So I just soldered a wire bridge across to the unused pole, and the switch now works perfectly again.   But how long that pole will last is another matter...   --   Jeff

Michael Black <et472@ncf.ca>: Dec 22 01:52PM -0500

"Arfa Daily" <arfa.daily@ntlworld.com>: Dec 23 01:08AM "Michael Black" <et472@ncf.ca> wrote in message news:alpine.LNX.2.02.1412221349210.4253@darkstar.example.org... > may be the problem. I recall not seeing anything on the LCD display until > I did put in batteries, but it's been a while.   > Michael   All valid observations, but any kind of older boombox will likely have a straightforward linear supply utilising a power transformer. The primary of such is almost invariably connected straight across the power socket, and so can be read on a meter set to ohms. The OP said that he had a reading of infinity across the AC ...   Whilst there might be a separate fuse, this is often not the case, protection being afforded by a thermal fuse buried in the primary. The on / off switch is also never in the primary circuit. This is always either a mechanical switch in the main low voltage supply rail, or a tactile switch read by the system control micro, which then outputs a control signal to turn on sleeping parts of the power supply.   If the unit uses a 'figure 8' AC socket, this is the first place to look. It is extremely common for these to go bad jointed, often on just about every pin. This can give the symptoms described, because not only is it the AC input socket, it also has a switch that 'rolls over' when the plug is inserted. This switch controls where the DC to run the set comes from i.e. either from the secondary side of the AC power supply, or from the batteries.   Arfa

Phil Allison <pallison49@gmail.com>: Dec 22 06:42PM -0800 Arfa Daily wrote:     > Whilst there might be a separate fuse, this is often not the case, > protection being afforded by a thermal fuse buried in the primary. The on / > off switch is also never in the primary circuit.     ** OK - what exactly does a buried thermal fuse "protect" - I mean the one shot variety as found in small to medium size transformers ?   Cannot be the transformer, since fuse operation it renders it unusable.   It does not limit the max current flow like a wire fuse, cos operation depends on a critical temp being reached.   The answer is, it protects the user from possible electric shock by preventing overheating damage to the transformer.   A thermal fuse disconnects the primary from the supply *before* the enamel insulation or the plastic bobbin become dangerously hot.       .... Phil

Bruce Esquibel <bje@ripco.com>: Dec 23 12:24PM > Checked the forum using keywords "GPX C971" got nothing.   > Googled using keywords "GPX C971 schematic" also nothing.   No surprise there.   GPX was probably an importer who bought stuff cranked out of chinese or korean factories and slapped their name on it.   It was real low end shit that mostly ended up in drug stores, flea markets and "wholesale distributors to the public".   If there was any service or repair on those, it probably was limited to bringing it back to where you bought it and crossed fingers they exchanged it or gave a refund.   You'll have to hunt and peck to make an attempt to repair it, but not sure what you'll learn from the experience except how low quality can something be made but if you put it in a fancy enough case, someone will buy it.   -bruce bje@ripco.com

Cydrome Leader <presence@MUNGEpanix.com>: Dec 23 04:10AM > solely on the basis of price. Until they do, they will never be the real > threat they have the potential to be.   > I'm reminded of the joke about Japanese products in "BttF 3".   it seems like a race to the bottom for most products though. Those of who who want quality over price are a very, very small minority when it comes to total numbers.   Hell, even Klein Tools is pushing chinese junk now.

"Arfa Daily" <arfa.daily@ntlworld.com>: Dec 23 01:20AM "Gareth Magennis" <sound.service@btconnect.com> wrote in message news:xcqdndpBw4IXoQnJnZ2dnUVZ7qqdnZ2d@bt.com...   > ... Phil   > This stuff is really good on pinch rollers. > http://www.amazon.co.uk/AF-International-Platen-Cleaner-Restorer/dp/B0012IKSHO/ref=sr_1_1?ie=UTF8&qid=1419000776&sr=8-1&keywords=platenclene   Oh you little darlin' Gareth ! This was one of my favourite workshop chemicals. I had one and it lasted years and years. When it ran out, I really mourned as I was unable to find it still for sale anywhere. As soon as Crimbo is out of the way, I will be ordering a can ! :-)   Arfa

"Arfa Daily" <arfa.daily@ntlworld.com>: Dec 23 01:26AM "Sofa Slug" <sofaslug@invalid.invalid> wrote in message news:m6ssvi$ifg$1@dont-email.me... >> a speed error, or am I wrong in making that assumption? Lenny   > I would put the correct belt on there before getting into other minutia, > otherwise you may just end up chasing your tail.   Seconded. I have had many Aiwas that use a single motor dual cassette deck come through my workshop over the years, that have had the main drive belts replaced with two of dissimilar thicknesses. One might be a 1 mm square section and the other 1.2 mm. When this is the case, it is impossible to get both decks running at the same speed, even though it is a single motor driving both. When two belts of the same thickness are fitted speed on both decks is identical.   Arfa

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