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micky <NONONOmisc07@bigfoot.com>: Feb 12 11:18AM -0500 In sci.electronics.repair, on Tue, 7 Feb 2017 21:12:57 -0000,   >Unless there's an overhead obstruction, you should be able to seat a drill >bit in the crosspoint recess and drill the head off. Removing the threaded >bit with only the thickness of the PCB to get hold of might be fun.   Use a reversible drill and left-handed drill bits. then theres a pretty good chance you'll unscrew the screw before you get done drilling. So you only have to replace the screw. Otherwise, you can glue it back together later.   Also, there is another kind of screwhead/screwdriver in with crossed slots, other than Philips. It's supposed to eliminate the need for more than one size of such a screwdriver. I don't know any place these scdrews are used by maybe you found one.   (Yes, I read the thread and know you finished this one but for next time.)

micky <NONONOmisc07@bigfoot.com>: Feb 12 11:45AM -0500 In sci.electronics.repair, on Tue, 7 Feb 2017 21:12:57 -0000, >> access, to grind flat blade slots in the screw heads or pairs of flats for >> mole-grips etc.   >Might be worth reading the; "Best Philips screwdriver" thread.   I can't find this. I looked back to before last June in SER, so where can I find it?   Also the screw style I meant was Pozidrive. Could that have been the difference?         >Unless there's an overhead obstruction, you should be able to seat a drill >bit in the crosspoint recess and drill the head off. Removing the threaded >bit with only the thickness of the PCB to get hold of might be fun.   Use a reversible drill and left-handed drill bits. then theres a pretty good chance you'll unscrew the screw before you get done drilling. So you only have to replace the screw. Otherwise, you can glue it back together later.   Also, there is another kind of screwhead/screwdriver in with crossed slots, other than Philips. It's supposed to eliminate the need for more than one size of such a screwdriver. I don't know any place these scdrews are used by maybe you found one.   (Yes, I read the thread and know you finished this one but for next time.)

micky <NONONOmisc07@bigfoot.com>: Feb 12 11:38AM -0500 Maybe you remember the thread where I asked about repairing the woofer that I found behind the rear seat of the convertible. I think I asked about the 4 wires going to the sound coil.   One of the wires was cut, and the speaker connector was disconnected.   To follow up, I plugged the speaker in for a bit before making any repairs and it sounded okay to me. No rattling, though maybe with louder music I would have heard some.   I replaced the foam surround that surrounds the speaker cone. I bought the parts from the more expensive place ($25 iirc) partly because I didn't know about the cheaper place then ($20). But the glue that came with it was very good.   Repair really was easy, like they claimed. It centered itself pretty much. Just move it up and down a couple times and it was centered so the voice coil wouldn't rub against the magnet.   I soldered the cut wire and put it back in the car, and now there is too much bass! I put the rear seat back back in place. Still too much. I used the bass control to lower it a notch, and it's still too much.. Well that was true for the first 2 or 3 weeks but I think I got used to it.   I wonder if that is what happened with the car. Supposedly owned by an old lady (with real evidence that I found later that that was true) maybe she wanted them to lower the bass, so they cut one of the 4 wires to cut the bass in half, and that wasn't enough so they disconnected it entirely. Later the surround rotted.   That's the only thing I can think of to explain why both the wire was cut and the connector disconnected.

micky <NONONOmisc07@bigfoot.com>: Feb 12 11:12AM -0500 In sci.electronics.repair, on Fri, 10 Feb 2017 19:52:15 -0500, micky   >So it seems like every dvdr etc. that is on automatic might have gained >a day today, and lost a day of recordings. Have any of you ever heard >of that before?   It may have gotten buried, but this was the point of the post. Have any of you ever heard of a timer in a DVDR or something losing or gaining a whole day in one step?   Which is more likely? Either an internal mistake or from some central place. For those who didn't know about this: Times are sent out from iirc PBS stations on PBS channels that are used by TV recorders like the times sent out on the internet to computers that are used to keep computer times accurate.

Mike Duffy <mqduffy001@bell.net>: Feb 12 11:33AM -0500 On Sun, 12 Feb 2017 11:12:55 -0500, micky wrote:   > iirc PBS stations on PBS channels that are used by TV recorders like the > times sent out on the internet to computers that are used to keep > computer times accurate.   Then probably it was a human error made by someone operating the device that does this encoding. There is no way for you to know because in all likelyhood everyone else except you uses their DVRs (not DVD recorders) to record TV programs, and most DVRs use the same protocol as your PC uses (NTP) to maintain synchronization.

John Robertson <spam@flippers.com>: Feb 11 09:39AM -0800 On 2017/02/09 8:35 PM, micky wrote:   > Or, is there ever a way to adjust this?   > No schematic is available, I'm pretty sure but its guts look like most > of them. .   Did you try a new battery in the meter? Weak batteries will give odd readings...   John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

jurb6006@gmail.com: Feb 12 02:47AM -0800 >"I hae opened up 3 of the 'free'or about $ 6 if just bought ones and they all have an adjustment pot. They all seem to be close enough compaired to my Fluke that I did not do any adjustment to that pot.   Have you actully opened up any ? "   About three of them, no pots.   Of course that does not mean they're all the same, I have encountered two distinct types at least, one has a power switch and the other simply has an "off" position on the range switch. (which I do not prefer)   Perhaps they were well hidden. At any rate, one pot for the whole thing would adjust all the ranges, so if only certain ranges are off then something else is wrong.   There are probably many different versions of these things. At work I stumbled across a Craftsman meter which is about the spitting image of one of these, but then we know Sears stuff is built by the lowest bidder. However I haven't taken that one apart, it works, I will see the inside when the battery dies I guess. It could be totally different but really I do not see the reason why. When they work right they seem to really work right, they agree with my decent Fluke and they agree with my buddy's even better Fluke.   I had one that would not zero on any range, they said don't even bother to send it back, they just sent a new one. Throwaway test equipment, ever thought you'd see it ?   But then a $300 guitar can be throwaway as well, really. My buddy bought an Ibanez acoustic with the electronic pickups. Sounded great actually, like a miced guitar and not much feedback. But the electronics quite. He calls and they gave him a full refund and said not to even bother sending it back. I bought it thinking maybe I would fix the pickup but never got to it, so I have me a decent acoustic. And that prick made $100 off of me. It does play really well though. He should have sold it to me for $50 though. But really, I started taking that guitar apart and the way they put the pickup in pretty much precluded any type of repairs. I swear, it should be illegal for electronics manufacturers to be in possession of any type of glue, and I mean death by slow torture for thee board of directors.

jurb6006@gmail.com: Feb 12 03:04AM -0800 >"I spoke of chance, and you refute my claim based on one single sample? "   No, several. Unless the pot is well hidden somewhere.   I have changed the batteries in a few, and one I wanted to somehow revamp and make it read like a benchtop DVM but once I saw the ubiquitous zebra strip I figured the chances of that were slim and none and slim has a bullethole in his head.   Thing about these tings is it is almost not worth changing the battery, depending on where you go it might cost you more than the whole meter.   But anyway, using this Google groups is getting to be a drag, no tree view so you have a hard time seeinf where your post goes, as in who it appears you are responding to. And now it doesn't like my old Firefox so I am in IE again. I used to have Thunderbird set up opn this thing but lost it somehow due to a system restore or something. I might just shoot the thing and be done with it.

Ralph Mowery <rmowery28146@earthlink.net>: Feb 12 10:24AM -0500 In article <c22213e5-34e4-46c9-aba6-dcc113c9e530@googlegroups.com>, jurb6006@gmail.com says...   > I had one that would not zero on any range, they said don't even bother to send it back, they just sent a new one. Throwaway test equipment, ever thought you'd see it ?   > But then a $300 guitar can be throwaway as well, really. My buddy bought an Ibanez acoustic with the electronic pickups. Sounded great actually, like a miced guitar and not much feedback. But the electronics quite. He calls and they gave him a full refund and said not to even bother sending it back. I bought it thinking maybe I would fix the pickup but never got to it, so I have me a decent acoustic. And that prick made $100 off of me. It does play really well though. He should have sold it to me for $50 though. But really, I started taking that guitar apart and the way they put the pickup in pretty much precluded any type of repairs. I swear, it should be illegal for electronics manufacturers to be in possession of any type of glue, and I mean death by slow torture for thee board of directors.     Most anything under $ 500 is a throw away now unless you can fix it yourself. With companies charging $ 50 to $ 100 per hour labor, the cost to ship it back, especially if it is big or heavy, all tht ammounts up fast. Sort of like the socket sets from 40 years ago with the lifetime warrenty. The whole set was about $ 5. If you sent the broken part back and $ 4.50 for retrun postage and handling, they would send you a replacement for the broken part.

John Robertson <spam@flippers.com>: Feb 11 09:38AM -0800 On 2017/02/11 7:38 AM, Ralph Mowery wrote:   > If the set had a solid state rectifier tube, you could pull all the > tubes and use the variac to see if the capacitors were shorted or some > other problems.   Replace primary electrolytic filter caps if it hasn't been running for many years. Running it with probably bad caps just stresses everything starting with the expensive transformer and working down from there.   You might try a 40 or 60 watt bulb to reduce the current available. Otherwise that is the same way we power up old jukebox equipment after it has been recapped.   John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

Foxs Mercantile <jdangus@att.net>: Feb 11 12:57PM -0600 On 2/11/2017 9:34 AM, Dave M wrote: > Best way to attempt reforming the electrolytic filters is to > remove the rectifier tube, then disconnect the wiring from > the electrolytics.   The best way to reform electrolytics is by replacing them with new ones and not wasting your time trying to reform the old ones.     -- Jeff-1.0 wa6fwi http://www.foxsmercantile.com

Ralph Mowery <rmowery28146@earthlink.net>: Feb 11 03:07PM -0500 In article <o7nmri$nbp$1@gioia.aioe.org>, jdangus@att.net says... > > the electrolytics.   > The best way to reform electrolytics is by replacing them with > new ones and not wasting your time trying to reform the old ones.   Well said. Anything very old just shotgun the electrolytics. They are not that expensive. You will probably save time in the long run.

Foxs Mercantile <jdangus@att.net>: Feb 11 03:00PM -0600 On 2/11/2017 2:07 PM, Ralph Mowery wrote:   > Well said. Anything very old just shotgun the electrolytics. > They are not that expensive. > You will probably save time in the long run.   I don't like call backs and I don't like working on the same radio twice. And I certainly don't like replacing shit that got ruined because I was too cheap to replace a $4 part.     -- Jeff-1.0 wa6fwi http://www.foxsmercantile.com

"Benderthe.evilrobot" <Benderthe.evilrobot@virginmedia.com>: Feb 11 09:02PM <oldschool@tubes.com> wrote in message news:c26t9cde4gr0r0vfcsamfu8am11c1f1eog@4ax.com... > wonder how this will work for the tube rectifier.... But my big concern > is the power transformer in the device. Can too low of a voltage harm > the power trans.?   A lot of people do it that way, but I'd worry about stripping the HT rectifier cathode.   I'd take all the tubes out and strap temporary silicon rectifiers on the rectifier socket.   You have to bring the voltage up very gently, but only the first 2 reservoir electrolytics are directly in the firing line.   The lower Vf of silicon rectifiers mean you can bring the HT up slightly higher than normal, so there shouldn't be any surprises when you re assemble it all with the original rectifier tube.   In theory; you should leave the capacitors energised for at least 12h to re form, but there must be some means of current limiting in case they break down - I certainly wouldn't leave a variac hooked up.   With all the tubes out - the temporary silicon with a 40W bulb in series with it should prevent any dangerous current flow.

"Benderthe.evilrobot" <Benderthe.evilrobot@virginmedia.com>: Feb 11 09:15PM "Ralph Mowery" <rmowery28146@earthlink.net> wrote in message news:MPG.3309391e37fe728c98983d@news.east.earthlink.net...   > Well said. Anything very old just shotgun the electrolytics. They are > not that expensive. > You will probably save time in the long run.   A lot of people go to extremes to maintain authenticity - for some; that means gutting the old electrolytics and hiding new modern ones in the original cans.   It doesn't save any time, but if you do a neat job its hard to spot.   Old electrolytics that need re forming isn't a fault condition - its a natural characteristic of aluminium electrolytics.   The electrolyte is caustic and very slowly etches away the oxide layer dielectric. Thinner dielectric means higher capacitance, but lower breakdown voltage.   Re forming simply grows the oxide layer back to its original thickness. The leakage current is what's doing the work - but you have to do it slowly or it overheats and/or breaks down.

Foxs Mercantile <jdangus@att.net>: Feb 11 04:23PM -0600 On 2/11/2017 3:15 PM, Benderthe.evilrobot wrote: > that means gutting the old electrolytics and hiding new modern ones > in the original cans.   > It doesn't save any time, but if you do a neat job its hard to spot.   BUT....those are NEW capacitors, not old ones that have been reformed.     > Re forming simply grows the oxide layer back to its original thickness. > The leakage current is what's doing the work - but you have to do it > slowly or it overheats and/or breaks down.   Which is still a waste of time. Once you've "reformed" the electrolytic, you're right back where you started from. A 50-75 year old part that needs replacing.     -- Jeff-1.0 wa6fwi http://www.foxsmercantile.com

Phil Allison <pallison49@gmail.com>: Feb 12 01:00AM -0800 Dave M wrote:       > that the rectifier tube won't start conducting until the Variac voltage is > pretty high, and if the electrolytics are very leaky, you risk damaging the > power transformer due to excessive current.   ** That is very doubtful.   Leaky electros get hot fast and will soon pour smoke. OTOH the power tranny will survive a moderate overload for hours while a bigger overload will pop the fuse.   > The transformer is the single most expensive and > hard-to-find component in the set. By all means, protect it.   ** Monitoring the AC current is all you need to do.     .... Phil

jurb6006@gmail.com: Feb 12 03:12AM -0800 I haven't done alot of tube stufff lately, but over the years I got the idea that all this variac and dim bulb stuff was for solid state where it can totally fry in microseconds.   Tube stuff I would just plug it in. Of course watch the rectifier, and then whatever other tubes, especially power tubes in there. Anything redplates pull it out and start again. Eventually you get down to seeing how much ripple is on the B+ and go from there. Things with selenium rectifiers are of course a different story, I do not need FEMA here evacuating the neighborhood and I am sure these ninnies today would do some shit like that.   But generally, tube stuff is very forgiving.

"Phoena Greene" <raeanne.is@ratchet.hoe>: Feb 11 10:24AM -0800 <thekmanrocks@gmail.com> wrote in message news:cc0795db-3c84-4cae-9a9d-aa47fabacf60@googlegroups.com... > the real blame lies with sites like Hulu and > YT constantlh "updating" their smart TV > apps.   If it was a "perfectly good player" it wouldn't be constantlh forgetting my Wifi password. Can't remember the last time Hulu and YT actually updated shit on the Sony blu ray player platform.   Remember that sticker that said "It's A Sony!" you would see on a Trinitron or a Betamax or a Walkman? When was the last time you saw "it's A Sony!" on a Sony Product? Can't even remember because even Sony knows their products have the quality of cockroach shit.

"Phoena Greene" <raeanne.is@ratchet.hoe>: Feb 11 10:30AM -0800 <ohger1s@gmail.com> wrote in message news:94af2970-0080-488d-b7eb-e8c2119d311e@googlegroups.com...   >> Rest in pieces, Sony blu Ray Player.   > Around here, you can't have AC anywhere near water without a ground fault > so you would need an extension cord.   Around here blu ray players come with a 12 volt power adapter which was plugged into a GFCI outlet and in 5 seconds the water from the sink destroyed the blu ray player much like Obama destroyed America.   > OTOH, if it fits, remove the top cover and place the offending equipment > in the microwave oven if you want a real visual treat....   Oh, it fits but am I going to waste a perfectly good microwave oven when a hammer that I got for 3 dollars at a flea market worked wonders.

ohger1s@gmail.com: Feb 11 07:05PM -0800 On Saturday, February 11, 2017 at 1:30:49 PM UTC-5, Phoena Greene wrote:     > Around here blu ray players come with a 12 volt power adapter which was > plugged into a GFCI outlet and in 5 seconds the water from the sink > destroyed the blu ray player much like Obama destroyed America.   Wow, even my crappy "smart" Vizio DVD has an AC cord..     > > in the microwave oven if you want a real visual treat....   > Oh, it fits but am I going to waste a perfectly good microwave oven when a > hammer that I got for 3 dollars at a flea market worked wonders.   I admit that there's a certain satisfaction to beating the beejeezus out of an offending device with a heavy blunt object, but you won't hurt the microwave if you decide to go Tesla on it. Just don't run the microwave too long lest you stink it up for weeks. A couple of seconds will reveal a light show to delight young and old alike, and not damage the magnetron.

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