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"pfjw@aol.com" <pfjw@aol.com>: Aug 02 12:43PM -0700 On Wednesday, August 2, 2017 at 12:19:19 PM UTC-4, John-Del wrote: > On Wednesday, August 2, 2017 at 10:00:17 AM UTC-4, fynn...@yahoo.com wrote: > But, but l am surprised the high level of respect for members in this group has gone down. Any way all is not lost yet people like Phil are always there to help.   > LOL...   Now, wait just a darned minute. Phil is quite reasonable when he takes his meds!   Peter Wieck Melrose Park, PA

rickman <gnuarm@gmail.com>: Aug 02 03:56PM -0400 >> But, but l am surprised the high level of respect for members in this group has gone down. Any way all is not lost yet people like Phil are always there to help.   >> LOL...   > Now, wait just a darned minute. Phil is quite reasonable when he takes his meds!   And which holiday would that be?   --   Rick C

"pfjw@aol.com" <pfjw@aol.com>: Aug 02 01:03PM -0700 On Wednesday, August 2, 2017 at 3:56:46 PM UTC-4, rickman wrote:   > And which holiday would that be?   The one celebrating the day he took his meds... .   Peter Wieck Melrose Park, PA

rickman <gnuarm@gmail.com>: Aug 02 05:08PM -0400 > On Wednesday, August 2, 2017 at 3:56:46 PM UTC-4, rickman wrote:   >> And which holiday would that be?   > The one celebrating the day he took his meds... .   Yeah, I think you are right, that would be a holiday.   --   Rick C

jurb6006@gmail.com: Aug 02 03:05PM -0700 I want to know what is wrong with using a five buck transformer rather than creating a shock hazard.   Such a scheme beats on the cap and it may go bad. In fact it may short out and teach you why they do not do this. Hopefully your fire insurance is paid up.   This is worse than those little transformerless cellphone chargers. They should not be allowed to sell those things.   There is a right way and a wrong way, and a capacitively coupled doodad like this is the wrong way.

John-Del <ohger1s@gmail.com>: Aug 02 03:25PM -0700 > Such a scheme beats on the cap and it may go bad. In fact it may short out and teach you why they do not do this. Hopefully your fire insurance is paid up.   > This is worse than those little transformerless cellphone chargers. They should not be allowed to sell those things.   > There is a right way and a wrong way, and a capacitively coupled doodad like this is the wrong way.       Yes, but I believe it was only an exercise in a class. But you can use this technique on the secondary of a transformer instead of using a dropping resistor, although I can't recall seeing it done.   The only time I used it was very recently on an old AC/DC radio from the 30s that had about 80V worth of filaments but needed to run on 120V. The radio originally used a resistive AC cord which consisted of two normal conductors and one length of asbestos yarn wrapped in a spiral of nichrome wire that ran the entire length of the AC cord and connected to one side of the AC plug. This long wire resistor provided the necessary drop for the filament requirement. The cord was shot so I put in a two wire cord and used something like 6uf worth of film caps out of Panasonic plasma sustain to get down to the proper voltage for the tube's series string. It's fused, but it's a temporary solution just to get the radio operational. If I ever restore the radio I'll probably locate a replacement cord as there's no room for a dropping resistor of the necessary wattage in the case (miniature mantle radio).

Phil Allison <pallison49@gmail.com>: Aug 02 09:13PM -0700 > I want to know what is wrong with using a five buck transformer > rather than creating a shock hazard.   ** No shock hazard if built sensibly.   Smoke detectors use dropping caps all the time.     > Such a scheme beats on the cap and it may go bad.   ** They sometimes go open.   > In fact it may short out and teach you why they do not do this.     ** A fuse or fusible resistor in series with the incoming AC is wise.     .... Phil

jurb6006@gmail.com: Aug 02 09:16PM -0700 Yeah, another thing that raises the cost of fire insurance.   I remember when GM used resistive wire as a ballast for the coil, which was shorted out during cranking by the extra terminal on the solenoid. We have advanced past that and resistive power cords. WE now know how to control power pretty accurately.   If you really must restore some old thing to its original, unsafe and inefficient state, by all means do so. But don't come crying to me if it burns your house down. Mainly, don't fall asleep with the thing running.   Sorry, I tend to err on the side of safety. Things need to be isolated and that means a transformer. A capacitive coupled device ? I would not have it in the house.   I have had dangerous things, for one guns. Then my buddy brings over this oxygen hydrogen separator that runs on 12 volts. And he didn't realize that it was better to separate those two gases, because together they are most dangerous.   He wanted to use it to boost his car, but we found out that the thing was pulling like 11 amps at 12 volts and the load on the alternator would negate most of the gain.   It is like what I have been saying, fossil fuel beats about anything, that is why it sells. When something better comes along, the oil companies won't be oil companies, they will be selling whatever it is.   But anyway, dropping voltage/current with a capacitor is not the way to do it. There are times when you just cough up the money for a transformer.

Phil Allison <pallison49@gmail.com>: Aug 02 09:54PM -0700 jurb...@gmail.com wrote:   ---------------------------   > Sorry, I tend to err on the side of safety. > Things need to be isolated and that means a transformer. > A capacitive coupled device ? I would not have it in the house.   ** Your toaster isn't isolated, nor is your hair dryer and a host of everyday appliances.   The only appliances that NEED isolation are electronic ones that have external connections to other devices. The rest can safely rely on being fully insulated or by safety grounding any external metalwork.   FYI: transformers do not automatically provide *safety isolation* unless that are designed to meet class 2 requirements. Very few off the shelf ones are.   Your constant posting of rambling drivel is getting worse - jurb.   You have way too many loose screws.       .... Phil

Mike Coon <gravity@mjcoon.plus.com>: Aug 03 07:58AM +0100 In article <8ead2f85-3e1b-4562-8b49-7325808a49ef@googlegroups.com>, jurb6006@gmail.com says...   > This is worse than those little transformerless cellphone chargers. They should not be allowed to sell those things.   Really? All the ones I have taken apart (and not just for cellphones) are switch-mode with tiny transformers. Admittedly I don't know how they make them miniature secure isolation devices...   Mike.

Phil Allison <pallison49@gmail.com>: Aug 03 12:27AM -0700 Mike Coon wrote:   --------------------   > > This is worse than those little transformerless cellphone chargers. > > They should not be allowed to sell those things.   > Really?   ** The term "transformerless" sometimes only means there is no iron transformer - just small ferrite cored one instead.   Nowadays,they can be made as SMD devices and be incredibly small for DC powers of 1 watt or so.       > All the ones I have taken apart (and not just for cellphones) > are switch-mode with tiny transformers. Admittedly I don't know how they > make them miniature secure isolation devices...   ** Enough insulation is there to tolerate the AC supply voltage and not fail from overloading.   The latest thing is a "piezo transformer" but I have no evidence that are being used in cell phone chargers.     .... Phil

Mike Coon <gravity@mjcoon.plus.com>: Aug 03 09:29AM +0100 In article <70593057-cc4c-4463-8dee-48b8e6b3def1@googlegroups.com>, pallison49@gmail.com says...   > The latest thing is a "piezo transformer" but I have no evidence that are being used in cell phone chargers.   I hadn't heard of that, but I suppose it is a no moving part (in usual interpretation of that phrase) motor+dynamo combination; brilliant!   Mike.

"fynnashba@yahoo.com" <fynnashba@yahoo.com>: Aug 03 04:23AM -0700 On Thursday, August 3, 2017 at 4:54:43 AM UTC, Phil Allison wrote:   > Your constant posting of rambling drivel is getting worse - jurb.   > You have way too many loose screws.   > .... Phil   thanks to you all for that fruitful discussion. As indicated by Phil its not all appliances that need to be duly isolated. A device like an automatic dawn to dusk light switch can be safe without an isolation transformer besides during the day the transformer's primary will still take some power and warm up. I have also seen a Chines made portable radio set without transformer. It was boldly written on it "transformerless AC radio" apparently the manufacturer was boasting. A guy opened it to find out what was inside and showed us this cap drop power supply so he warned the friend against possible electric shock when he touch any metal part. the friend replied there were no metal parts so its safe. Not long before that he got zapped when he forgot that the antenna was made of metal. l am going to let him read all your post. Thanks once again. i ve asked him to read all your post

John-Del <ohger1s@gmail.com>: Aug 03 04:35AM -0700 > If you really must restore some old thing to its original, unsafe and inefficient state, by all means do so. But don't come crying to me if it burns your house down. Mainly, don't fall asleep with the thing running.   If you're referring to the resistance line cord in my example, there aren't many options even if you don't care about originality (I don't). That radio in my example has 5 tubes, two IF XFRs, a gang tuner and a dynamic speaker all crammed into a 4X10 chassis pan. The plastic cabinet covers this like a glove. There's simply no room to mount a 25W resistor or mitigate the heat that it produces.   Still, in the trade, the resistive AC line cord was known as a "curtain burners" because people would often coil them up in a neat little ball instead of spreading them out as the owner's manual directed.   I do restore an occasional antique radio for my customers, and even after adding fuses and polarized line cords to them, I instruct them on the dangers of line connected metal chassis and never plug in the radio if one of the plastic knobs falls off. I also instruct them to leave all old radios unplugged when not in use and to not leave them running unattended.

"pfjw@aol.com" <pfjw@aol.com>: Aug 03 05:39AM -0700 The sovereign remedy for a curtain-burner is a unique plug to an external box that contains the resistor and heat-sink assembly. A nice, fat DALE aluminum resistor of the appropriate rating does well.   In this way, the radio does not get plugged into the wall by accident (nor anything else), and the external box can have a fuse, switch and other niceties as well as serve multiple radios.   Safety is a good thing, and despite the fact that our parents survived all sorts of deadly things such as a lack of seat belts, hard dashboards, Open-mesh electric fans with metal blades, and much more, there is no reason to lean into a punch.   Peter Wieck Melrose Park, PA

John-Del <ohger1s@gmail.com>: Aug 03 06:33AM -0700 > The sovereign remedy for a curtain-burner is a unique plug to an external box that contains the resistor and heat-sink assembly. A nice, fat DALE aluminum resistor of the appropriate rating does well.   > In this way, the radio does not get plugged into the wall by accident (nor anything else), and the external box can have a fuse, switch and other niceties as well as serve multiple radios.   True, but that doesn't preclude the possibility that someone in the future will find the radio, cut off it's unique plug, and replace it with a standard AC cord. The radio also loses some of it's charm having to be connected to a life support box instead of being independent.   BTW, does anyone else remember the Sanyo/Fisher receivers of the 80s that used LV AC taps off the transformer to power the matching Sanyo/Fisher tuner, CD, and cassette deck? I saw a bunch that had the unique plugs cut off and replaced with regular AC plugs. Feeding 120V into a tuner that worked on 16VAC left a big black smudge inside the cabinet.   The 1930s radio in question was only powered up with capacitive voltage dropping as a triage to assess the rest of the radio. I haven't yet decided whether to restore it. If so, I may keep the capacitors and add a diode, fuse, and zener crowbar to eliminate any possibility of a shorted cap running amok. These things can be safely installed below the deck and produce no heat.

"pfjw@aol.com" <pfjw@aol.com>: Aug 03 07:42AM -0700 Generally, if I make any sort of functional change to any given radio - dropping resistor, dropping capacitor, whatever, a 3 x 5 card will go under the chassis with such notes on it. I am not above using an etcher as well to make sure that something really important is not lost over time.   Stuff "below the chassis" has its significant advantages but unless explained becomes a mystery to the next user.   Peter Wieck Melrose Park, PA

Jeff Liebermann <jeffl@cruzio.com>: Aug 02 08:51PM -0700 On Tue, 01 Aug 2017 20:16:14 -0700, Jeff Liebermann <jeffl@cruzio.com> wrote:   >There seems to be a proposed law banning methylene chloride, but it >seem to have NOT been enacted quite yet. I seem to recall that I can >still buy the stuff at the local hardware store. I'll check tomorrow.   I went to the local hardware store and methylene chloride furniture stripper is still available: <http://www.learnbydestroying.com/jeffl/crud/Furniture%20Stripper.jpg> Just about everything from the center of the photo to the right would disappears if the methylene chloride was banned. I bought some of the Jasco epoxy stripper and plan to check if it will soften epoxy glue.     -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

jethro tull <heavytull@outlook.com>: Aug 02 08:58PM I'm searching for the datasheet of a component which I think is a voltage regulator and is from a 2 batery powered cd player which has several such components and which reference code as printed on is "GY139" and which photo is here : http://picpaste.com/GY139-bhTrEixQ.jpg   Another similar component on the same board is marked "KY139". I have not been able to find anything with these part numbers.

dansabrservices@yahoo.com: Aug 02 05:49PM -0700 On Wednesday, August 2, 2017 at 4:58:16 PM UTC-4, jethro tull wrote: > here : http://picpaste.com/GY139-bhTrEixQ.jpg   > Another similar component on the same board is marked "KY139". I have not been > able to find anything with these part numbers.   See the PDF here: http://www.kexin.com.cn/pdf/2SD2403-HF.PDF   This is for a 2SD2403 which has the code GY.   The KY appears to be either a 2SK211 or 2SK811 from what I can find.     Dan

jethro tull <heavytull@outlook.com>: Aug 02 08:21PM > Near as I can tell, this is a DTA114. If I get a chance, I'll look up the > service manual and verify.   > Dan I searched quite a lot for the service manual of this player and found nothing. I think sony does not like sharing such data.

Adrian Caspersz <email@here.invalid>: Aug 02 09:58PM +0100 On 02/08/17 21:21, jethro tull wrote:   >> Dan > I searched quite a lot for the service manual of this player and found nothing. > I think sony does not like sharing such data.   Hmmm, "WM-BF23"   The Canadian WM-AF23 is probably similar, looking at the   www.manualscenter.com/manuals/sony/wmbf23-service-manual.html   So have a look at   https://elektrotanya.com/sony_wm-af23.pdf/download.html   Look for the line,   This file is downloadable free of charge:   and wait for the "Get Manual" link to appear next to it.   Do not click any other download buttons!!     -- Adrian C

Adrian Caspersz <email@here.invalid>: Aug 02 10:05PM +0100 On 02/08/17 21:58, Adrian Caspersz wrote: >> I think sony does not like sharing such data.   > Hmmm, "WM-BF23"   > The Canadian WM-AF23 is probably similar, looking at the   Hmmm (2) - Scrap that, can't see the PNP part you mentioned.   -- Adrian C

jethro tull <heavytull@outlook.com>: Aug 02 10:06PM > This file is downloadable free of charge:   > and wait for the "Get Manual" link to appear next to it.   > Do not click any other download buttons!!   I got it. This player is slightly different in the circuit. The 5 and 6-pin IC's are not on mine. as for IC's I only have the tuner, the amplifer and the transistor I'm searching the part number with this post. But I'm surprised because the only difference the AF23 has with mine is the "normal / CrO2" switch which does "DX / local" when radio is on while for my device it does "mono / stereo". While this shouldn't affect significantly the amplifier stage, it does. The transistors around the pre-amp stage are not the same and the 5 and 6-pin IC's are being used here.

dansabrservices@yahoo.com: Aug 02 05:43PM -0700 On Wednesday, August 2, 2017 at 4:21:35 PM UTC-4, jethro tull wrote:   > > Dan > I searched quite a lot for the service manual of this player and found nothing. > I think sony does not like sharing such data.   I was a warranty service center for Sony, so I still have the service manuals on disc. I won't get a chance to fire the system up until Friday though.   Dan

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