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ohger1s@gmail.com: May 02 10:34AM -0700 On Tuesday, May 2, 2017 at 11:57:29 AM UTC-4, cl...@snyder.on.ca wrote: Luckily I had > alcohol or any othe substance was effective in returning the block to > the proper size. No idea what kind of plastic it was- but it sure > didn't like WD-40.   I've heard of certain materials that swell in the presence of oils. Maybe it wasn't the solvent in the WD but the mineral oil it contains. IOW, any spray with mineral oil might have had the same effect.

Micky <misc07@bigfoot.com>: May 02 11:00PM +0300 On Tue, 2 May 2017 08:39:44 +0100, Ian Jackson >years, but which has been your saviour on the odd occasion when you've >suddenly needed a general-purpose lubricant / switch cleaner / rusty nut >freer / corrosion inhibitor ?   I think there are 3 topics you're not supposed to talk about at work (since you have to continue to see those people): politics, religion, and WD-40.

dplatt@coop.radagast.org (Dave Platt): May 02 12:56PM -0700 >> didn't like WD-40.   >I've heard of certain materials that swell in the presence of oils. Maybe it wasn't the solvent in the >WD but the mineral oil it contains. IOW, any spray with mineral oil might have had the same effect.   According to the chart at   http://www.plasticsintl.com/plastics_chemical_resistence_chart.html   mineral oil has a "C" compatibility rating for polycarbonate and polypropylene ("Moderate attack of appreciable absorption. Material will have limited life.")   For "Lubricating oils (petroleum)" HDPE also gets a "C" rating.   For "white spirit", the plastics listed are all either "A" (no attack, possibly slight absorption, negigible effect on mechanical properties) or "*" (no data available).

rickman <gnuarm@gmail.com>: May 02 05:22PM -0400 >> the proper size. No idea what kind of plastic it was- but it sure >> didn't like WD-40.   > I've heard of certain materials that swell in the presence of oils. Maybe it wasn't the solvent in the WD but the mineral oil it contains. IOW, any spray with mineral oil might have had the same effect.   Does it really matter which component of WD-40 causes the problem or if other products cause the same problem? The point is that WD-40 is not a good product to use on electrical devices unless you know the materials won't be affected by it.   Some people here are in denial about the issue and refuse to consider that anything other than their own personal experience constitutes reality. You seem a bit more reasonable.   --   Rick C

ohger1s@gmail.com: May 02 02:36PM -0700 On Tuesday, May 2, 2017 at 5:22:46 PM UTC-4, rickman wrote:   > > I've heard of certain materials that swell in the presence of oils. Maybe it wasn't the solvent in the WD but the mineral oil it contains. IOW, any spray with mineral oil might have had the same effect.   > Does it really matter which component of WD-40 causes the problem or if > other products cause the same problem?   For the purposes of the discussion, I think it does. If most spray elixirs use some sort of petroleum based oil that has a long term affect on certain plastics, then it's not fair to single out WD40 particularly. In any case, I don't recall any other spray solutions that use a synthetic lube that trumpet the fact that they are safe for all plastics. If WD had a known issue with plastics, someone (if not the WD folks) would surely step in with a fix product to steal the sales.     The point is that WD-40 is not a > good product to use on electrical devices unless you know the materials > won't be affected by it.     That's good advice for any external additive. I always test the material in question. Still, other than the fellow with the swollen window blocks (probably an interference fit as it was designed), I think WD-40 will have no affect on electrical connectors.       > Some people here are in denial about the issue and refuse to consider > that anything other than their own personal experience constitutes > reality. You seem a bit more reasonable.   I don't even use the stuff...

Clifford Heath <no.spam@please.net>: May 03 07:52AM +1000 On 02/05/17 21:43, Jeff Layman wrote: >> protecting tools *with something else*.   >> Try the test.   > I have, many times. It just works.   Not hear, it doesn't. Very humid and warm, and any unprotected tools repeatedly get surface rust, despite treatment with WD-40. I must buy some proper anti-rust spray, and use it after I've de-rusted everything in the citric acid bath.

rickman <gnuarm@gmail.com>: May 02 06:10PM -0400 > for all plastics. If WD had a known issue with plastics, someone (if > not the WD folks) would surely step in with a fix product to steal > the sales.   I don't know what "fair" has to do with it. Someone suggested using WD-40 as a contact cleaner and I as well as a couple others pointed out it can cause problems. Others disputed this. Bottom line it WD-40 is not safe to use without checking the materials in use. There are many products that are specifically intended as contact cleaners which don't cause these problems.     >> good product to use on electrical devices unless you know the >> materials won't be affected by it.   > That's good advice for any external additive.   Exactly. Some here have said WD-40 is universally safe to use when it is not.     > I always test the > material in question.   How exactly do you do that without using it on the product in question?     > Still, other than the fellow with the swollen > window blocks (probably an interference fit as it was designed), I > think WD-40 will have no affect on electrical connectors.   I can't say that universally. As I mentioned, a friend used it on an expensive piece of chemical instrumentation and it froze the controls. I guess if the problem is caused by swelling the material and the connector has a very loose fit, it might not cause a problem. But why take the chance when there are other products that just plain *won't* cause a problem?       --   Rick C

Phil Allison <pallison49@gmail.com>: May 02 07:18PM -0700 Peter Fuckwit wrote:     > WD-40 is not designed to remove or protect against rust either.   ** IME it does both and it say so on the can too.     > WD-40 is neither voodoo, black magic nor a secret potion.   ** Wot an idiot "straw man" to bring up.   Proves you know fuck all about the many uses of WD40.       ..... Phil

Phil Allison <pallison49@gmail.com>: May 02 07:23PM -0700 Peter Fuckwit wrote:     > > ** Which is refined petrol, aka lighter fluid.   > The MSDS for WD-40 is posted previously.   ** Irrelevant.   The WD40 company regularly changes the terminology used.   It used to say it was mostly naptha.   The hydrocarbon propellant was changed to CO2, a couple of decades back.   Maybe that explains Global Warming....     .... Phil

Phil Allison <pallison49@gmail.com>: May 02 07:33PM -0700 Dave Platt wrote:     > According to the chart at   > http://www.plasticsintl.com/plastics_chemical_resistence_chart.html   ** Irrelevant - cos charts like that are based on long term contact.   The solvents in WD40 **vanish** after a short time leaving only mineral oil behind.   Do you own tests and you will see nothing happens.   BTW: you are being a PITA troll.     .... Phil

Phil Allison <pallison49@gmail.com>: May 02 07:39PM -0700 Prickman the Liar wrote:         > Does it really matter which component of WD-40 causes the problem   ** There simply is NO problem.   You bullshitting IDIOT !!!!!       > Some people here are in denial about the issue and refuse to consider > that anything other than their own personal experience constitutes > reality.   ** They are the sane people.   You are a deluded idiot.           ..... Phil

Phil Allison <pallison49@gmail.com>: May 02 08:48PM -0700 Prickman is a damn LIAR wrote:   -----------------------------   > Someone suggested using > WD-40 as a contact cleaner and I as well as a couple others pointed out > it can cause problems.   ** Massive LIE.   It is simply not possible to "point out" a non-existent problem.   You are PF are clueless mental retards who post nothing but BULLLSHIT.       > Others disputed this.   ** Yeah - all the sane ones here.     > Bottom line it WD-40 is > not safe to use without checking the materials in use.     ** Insane, absurd, fucking crazy BULLSHIT !!!     > There are many > products that are specifically intended as contact cleaners which don't > cause these problems.   ** MASSIVE LIE !!!!   There are no such products cos there is no such problem.   The term "contact cleaner" is not clearly defined - products just like WD-40 can be called that name.   If a spray can product evaporates in seconds and leaves no oily residue - it WILL NOT FIX noisy pots or intermittent switches and the like.   To do that job requires a good grease solvent that lingers and a light oil to provide metal surface protection.   FFS ** fuck OFF ** - you WD40 hating LUNATIC !!!       .... Phil

Foxs Mercantile <jdangus@att.net>: May 02 11:17PM -0500 On 5/2/2017 10:48 PM, Phil Allison wrote:   > To do that job requires a good grease solvent that > lingers and a light oil to provide metal surface > protection.   This is why I use De-Oxit as a cleaner and follow up with Fader-lube on controls and Pro-Gold on switches.   The only things I use WD-40 for are: 1. Hosing a distributor cap and ignition wiring after it's gotten wet. I used to do this regularly with a '65 Dodge Slant-six engine. 2. Removing labels from equipment and the adhesive residue. 3. Occasionally spraying to the of my table saw. (It's cast iron.) 4. Using it instead of ether as a spray starter for 2-cycle engines. (Like chain saws and the like.) Although I think they stopped using propane as a propellant.     -- Jeff-1.0 wa6fwi http://www.foxsmercantile.com   --- This email has been checked for viruses by AVG. http://www.avg.com

Stephen Wolstenholme <steve@easynn.com>: May 02 10:19AM +0100 On Mon, 1 May 2017 15:51:57 -0700 (PDT), "pfjw@aol.com" <pfjw@aol.com> wrote:   >Oil of Pennyroyal. Gets rid of anything. DOES NOT KILL - drives stuff away, from fleas to spiders.   and humans. Since it invaded my garden I can't sit outside.   Steve   -- Neural Network Software for Windows http://www.npsnn.com

rickman <gnuarm@gmail.com>: May 02 10:33PM -0400 On 5/1/2017 9:33 AM, Stephen Wolstenholme wrote:   >>> We are about to bring in new matress and whatever, but anything happening to this laptop IS NOT AN OPTION.   >> The battery won't like being hot.   > The battery can be removed in most Laptops.   Not the lithium clock battery.   --   Rick C

Jeff Liebermann <jeffl@cruzio.com>: May 02 09:11AM -0700 On Tue, 2 May 2017 07:01:32 -0700, Taxed and Spent   >it includes a bandpass filter, although apparently Channel Master wants >to keep that a secret! >from http://www.warrenelectronics.com/antennas/Jointennas.htm   Thanks for the details on the device. As you've noticed, there is much more going on behind the curtain.   Under the heading on the above page: "(For blocking or passing a single channel)"   "JoinTennas are NON-RETURNABLE! Limited to stock on hand - no back-orders!"   There seems to be more than one model. In the "Antenna Coupler Typical Applications" on the right of the page, the 3 examples show some of the part numbers to be: Model 0578, Model 0585-2, Model 0576, and Model 0579   The multiple models, combined with the non-returnable ordering suggests that this is a custom device, tuned to frequency. The chart at the bottom of the page shows only a few UHF channels available. UHF Channels Avail. Model* 17, 18, 19 0585-1 53, 54, 55, 57, 58 0585-2 which is odd as other model numbers are mentioned under "Antenna Coupler Typical Applications". The limited channels may be only what the dealer stocks for his local channels.   The filter must be rather wide as the warning suggests: "Note: There is significant attenuation on either side of the channel the JoinTenna is tuned for. We do not recommend using a JoinTenna if you are trying to receive a channel adjacent to your specified channel."   None of this appears on the product page, data sheet, or installation manual: <https://www.channelmaster.com/JOINtenna_p/cm-0500.htm>   I like the first users comments: "Having a rotating antenna was not the solution because with today's digital tuners, every time you rotate the Antenna, you must rescan your channels." I guess he doesn't know how to manually add channels.   >JoinTenna blocks all frequencies but the one it is tuned for, >eliminating the ghosting and reflection that can happen when you connect >two antennas together.   With digital TV, one does not see ghosting or reflections on the screen. The modern term is "multipath". <http://www.hdtvprimer.com/ANTENNAS/glossaryG.html#multipath>   <http://www.hdtvprimer.com/ANTENNAS/siting.html> See section under "Skyline Multi-path".   If it blocks everything except the channel to which it's tuned, it must contain a BPF (bandpass filter) which adds some loss. The -2dB loss specified seems rather optimistic. The splitter/combiner typically has -1dB loss. A single channel BPF would have somewhat more than -1dB. My guess(tm) is the loss through the device is somewhat more than -2dB. There might also be a corresponding notch filter on the other port, also with some loss.   Seems like this device is a usable solution if: 1. One antenna is intended to only receive one distant station. 2. The signal strengths of most stations are strong to overcome the losses.   I think it fair to suggest that Channel Master would not have gone though all the trouble of installing filter(s) if there was no problem with interaction between antennas using a combiner.     -- 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

Clifford Heath <no.spam@please.net>: May 03 07:47AM +1000 On 03/05/17 02:11, Jeff Liebermann wrote:   > I think it fair to suggest that Channel Master would not have gone > though all the trouble of installing filter(s) if there was no problem > with interaction between antennas using a combiner.   It seems as though it should be straightforward to feed power up the co-ax (ala masthead amplifiers) to drive a pair of isolation amps/buffer before a combiner. That could give you a lot more isolation, without needing to go to relays.   Clifford Heath.

"Ron D." <ron.dozier@gmail.com>: May 02 03:22PM -0700 I like the first users comments: "Having a rotating antenna was not the solution because with today's digital tuners, every time you rotate the Antenna, you must rescan your channels." I guess he doesn't know how to manually add channels.   That's not as far-fetched as you would think.   with current Samsung so called "Smart TV's" it's not possible to add a channel. I have confirmation from Samsung.   USUALLY you can use the remote to select the physical channel and the TV will tune to the first virtual channel on that frequency. This is the preferred way the US government would like it to work. Channel up/down will then tune the sub-channels.   I don;t yet have confirmation that an unscanned channel works that way, but I think it will.   I have a TV tuner that will not work that way at all. It reports the actual center frequency in MHz of the scanned channels, not the physical channel, but you need the physical channel to add a single channel. You basically "scan" the physical channel and add. This "stupid" $1000 tuner won;t even update the display when entering a channel digit. The on-screen display shows the remote entered digit. The display on the tuner does not.   A CECB I have allows one to add "scanned" channels to the existing scan.

"Ron D." <ron.dozier@gmail.com>: May 02 03:31PM -0700 Incidently, The CECB reports signal strength in 0 to 100 arbitrary units. The "Dumb" Samsung TV just reports s/n ratio The $1000 tuner reports both s/n and signal strength in real units.

Jeff Liebermann <jeffl@cruzio.com>: May 02 05:28PM -0700 On Wed, 3 May 2017 07:47:12 +1000, Clifford Heath <no.spam@please.net> wrote:   >amps/buffer before a combiner. That could give you a lot more isolation, >without needing to go to relays.   >Clifford Heath.   Nope. The lack of isolation is NOT in the combiner. Assuming a reasonable 75 ohm termination on all ports, a good combiner can deliver 20 to 50dB isolation over the VHF-UHF TV band. I could replace the splitter/combiner with a 6dB resistive power divider/combiner, which has 6dB of isolation, and get the same problems at a 3dB lower signal level. Resistive power divider/combiner: <https://www.microwaves101.com/encyclopedias/resistive-power-splitters> A proper splitter: <http://802.11junk.com/jeffl/crud/CATV-splitter.png> Good splitter/combiner and total crap splitter/combiner: <http://802.11junk.com/jeffl/crud/CATV-splitters.jpg>   Anyway, the problem is the isolation between antennas. If both antennas can pickup the same signal, from the same station, the signals are going to add or cancel depending on the phase and amplitude. If there is a phase delay between these two signals, they will act much exactly as if there was a multipath problem. ATSC 8-VSB has some limited protection against multipath, but I wouldn't count on it. The symptoms manifest themselves as everything that could possibly trash a DTV signal. Fluttering, Stuttering, freezing, pixellation, rainbow color light shows, signal loss, etc. As I mentioned in a previous rant, the degree of cancellation and impairment is frequency dependent, which means I can't easily use a simple phase shifter to remedy the situation. I found some reference which suggested that one can see ghosts on a DTV with multipath. I never saw it or if they were there, they were buried under the light show and pixellation.   Someone is sure to ask why then do two stacked antennas work? <https://www.google.com/search?q=tv+antenna+stacking&tbm=isch> These work because both antennas involved are looking at the same station, which produces the same signal level at the same phase at each antenna. Therefore, they can safely be combined, where the two signals add in phase, and therefore produce 3dB more effective anenna gain.   Incidentally, I originally started by building a DPST PIN diode switch which selected which antenna was active by which coax cable had DC supplied to it. However, I made a stupid mistake and couldn't get it to function correctly. Since I was burning time and loosing money on this particular customer, so I took the easy way out and used a pair of spare latching relays and two push buttons from an HF antenna tuner project.   Bottom line: RF is magic. -- 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

Jeff Liebermann <jeffl@cruzio.com>: May 02 06:01PM -0700 On Tue, 2 May 2017 15:22:23 -0700 (PDT), "Ron D." >I guess he doesn't know how to manually add channels.   >with current Samsung so called "Smart TV's" it's not >possible to add a channel. I have confirmation from Samsung.   Sigh. I've been told to avoid anything called amazing, magic, miracle, plus, super, and such. I guess I now have to add smart to the banned list.   I just checked a Visio VX240M TV: <http://802.11junk.com/jeffl/crud/Visio%20Channel%20Skip.jpg> It starts out by skipping all channels and sub-channels. You can then go down the shopping list of channels and select which ones to NOT skip. Kinda backwards, but easy enough. The TV also has a "limited scan" which allows the user to set channel areas to re-scan complete with limiting the scan to digital, analog, or both.   I have a Samsung TV at home. I'll see what it can do later tonite. - >remote entered digit. The display on the tuner does not.   >A CECB I have allows one to add "scanned" channels to the >existing scan.   Nice mess. In the daze of analog TV VSB (vestigial sideband), the frequency of a TV channel was by the carrier frequency. This worked because the signal was asymmetrical. Symmetrical modulation schemes, such as FM, used the center frequency. SSB continued to use the carrier frequency. Meanwhile, the FCC uses the center frequency for most everything. Along came DTV, without a carrier frequency, so it was decided to use the center frequency. That generally satisfied the tech types.   However, the station owners wanted to retain their old channel designators, even if the channel frequency was quite different. This was allegedly to avoid listener confusion, but did quite the opposite. I was told that it was temporary, but that doesn't seem to be happening. The best laid plans...   One way to avoid having to deal with two sets of channel numbers would be to replace the real OTA channel number with that channels center frequency. That's apparently what was done in your expensive tuner. Whether the GUM (great unwashed masses) could handle the concept is debatable. They certainly are having problems with todays virtual channel system.   Another proposal that came and went was to replace the virtual channels with the stations call letters. This probably would have worked with an internet connected TV that could search a suitable database. However, the present system was thrown together before most everyone had internet available, so that went nowhere.   -- 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

Jeff Liebermann <jeffl@cruzio.com>: May 02 06:17PM -0700 On Tue, 2 May 2017 15:31:40 -0700 (PDT), "Ron D." >The CECB reports signal strength in 0 to 100 arbitrary units. >The "Dumb" Samsung TV just reports s/n ratio >The $1000 tuner reports both s/n and signal strength in real units.   The 0 to 100 is not quite arbitrary. It starts out as an 8 bit number (0 to 255) from the receiver demodulator. That gets fed to a microprocessor, which converts it to 0 to 100. That's because most users do not count in binary or hex, and must therefore be supplied with their numbers in decimal format. Seems rational. In cellular handsets, there is a conversion algorithm or lookup table that relates actual signal strength at the receiver input to the 0 to 100 numbers.   There is also a conversion to the number of bars (usually 5 bars), which are totally at the discretion of the handset manufacturer. That's what got Apple in trouble when they initially provided a linearized conversion from RSSI to bars and discovered that it made the iPhone 4 looks bad when the user grabbed the antenna.   Ok, back to the TV. The SNR (signal to noise ratio) in not the usual analog style: (signal + noise + distortion) / (noise + distortion) Instead it's based on the BER (bit error rate) or MER (modulation error rate). Basically, it's a measure of how many errors the receive has to deal with in order to display a decent picture. The more errors that need correction, the lower the SNR. I believe that there's yet another lookup table correlating the BER to what the SNR would be if it were an analog receiver, but I'm not sure that this is really true. <http://blog.solidsignal.com/content.php/2768-DTV-Antenna-Help-and-a-touch-of-SNR-BER-MER>   What I wanna see is Eb/N0 (energy per bit to noise power spectral density ratio): <https://en.wikipedia.org/wiki/Eb/N0> This for European DVB, but the theory is about the same for US DTV: "Bit Error Ratio BER in DVB as a Function of S/N" <https://cdn.rohde-schwarz.com/pws/dl_downloads/dl_application/application_notes/7bm03/7BM03_4E.pdf>       -- 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

Clifford Heath <no.spam@please.net>: May 03 12:26PM +1000 On 03/05/17 10:28, Jeff Liebermann wrote: > of spare latching relays and two push buttons from an HF antenna tuner > project.   > Bottom line: RF is magic.   Ok, well in that case, just use an imposed DC level (+ve or -ve) to enable one of two switch diodes. Whichever diode is forward biassed passes that antenna's signal. Simpler and cheaper than relays.   Clifford Heath.

"Ian Field" <gangprobing.alien1@virginmedia.com>: May 02 07:40PM +0100 "James Doyle" <nc4fl@hotmail.com> wrote in message news:9f89b65c-eefa-45bd-8737-336d38d24ee0@googlegroups.com... > need a ribbon cable for display board, wave radio AWR1-1W .. > jim nc4fl@hotmail.com   Not everyone has seen the insides of one of those - you need to be a little more specific.   There's wire ribbon cable of various types, and a few kinds of mylar flexiprint - and many different methods of termination.   Your first port of call is to find out if its available as a service replacement - but that could well cost as much as just replacing the radio.   Describe the part and someone might be able to suggest a fix.

Jon Elson <jmelson@wustl.edu>: May 02 02:29PM -0500 James Doyle wrote:   > need a ribbon cable for display board, wave radio AWR1-1W .. > jim nc4fl@hotmail.com Digi-Key has a whole area of board to board jumpers and specialty cables. You might poke around in their web site and see if you can find something that is at least a close match.   Jon

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