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bud-- <null@void.com>: Jun 02 04:32PM -0600 On 6/1/2015 12:50 AM, Phil Allison wrote:   >> Link to the IEEE surge guide was in my first post. Excellent information >> from a completely reliable source.   > ** Fraid it is neither.   https://en.wikipedia.org/wiki/Institute_of_Electrical_and_Electronics_Engineers The IEEE currently has 400,000 members.   The surge guide comes from the Surge Protection Devices Committee. That is people who actually design surge protectors and protection schemes. They also write standards for surge protection.     > Nothing more than a simplistic, broad overview with no examples of any commercial products.   > It does NOT say what you claim.   For anyone with minimal reading skills, it shows how surge protectors are connected and how they work (at least in the US). Namely MOVs from H-N, H-G, and N-G.     >>> ** Insane crap.   >> The problem I described,   > ** Listen you pompous halfwit:   So do I trust people who actually design surge protection and have done basic research, all of whom support what I have written?   Or do I trust Phil, who is currently in troll mode?   ...that's a tough one...

Phil Allison <pallison49@gmail.com>: Jun 02 09:23PM -0700 bud the dope -- wrote:     ( snip piles of irrelevant crap about the IEEE)     ** Listen you pompous halfwit:   the ** SAFETY HAZARD ** I am referring to is severe electric shock delivered to the user of the device.   Have you no idea how that can happen with MOVs wired to ground in a plug in device? ??   Obviously not - since the IEEE etc docs you linked do not bother to mention it.   Do I really have to rub your stupid nose in it ?   And you still have NO damn clue about the electric shock hazard inherent in connecting a MOV, cap, resistor or any sort of load from the current carrying conductors to safety ground inside a plug-in device.   Obviously, you cannot answer these important points.   FYI:   The executive director of the IEEE is a guy I went to high school and university with - Jim Prendergast.   https://www.ieee.org/about/management_council.html?WT.mc_id=lp_ab_imc   Totally irrelevant, of course.     ... Phil

Cydrome Leader <presence@MUNGEpanix.com>: Jun 03 03:40PM > https://www.ieee.org/about/management_council.html?WT.mc_id=lp_ab_imc   > Totally irrelevant, of course.   > ... Phil   I have to agree with Phil here. The key here is plug-in device. This is why "surge strips" or any sort of power strip with surge supression are just pure trash.   when these devices are not on fire, and are able to shunt some sort of surge, real or imagined into ground, you elevate the voltage on that segment of the ground circuit. That destroys or interferes with all the other equiment connected to that that ground.   Keep in mind lots of grounds aren't even really grounded, or grounded properly, especially in homes, old homes or places with poorly done electrical work. The end of the line is the worst place to try to stop a surge.   I had to remove some walls in a new space office space and wiring we found was appalling. Had to have the building engineer drop by to take a look for himself. He was baffled as well. Disconneting the weird wiring even resulted in one light switch causing the lights to just flicker instead off turn off in the off position. It wasn't even a two way switch.

"Mark Zacharias" <mark_zacharias@labolgcbs.net>: Jun 03 07:35AM -0500 "Arfa Daily" <arfa.daily@ntlworld.com> wrote in message news:nF6bx.548189$rk1.509613@fx44.am4... > been doing them for years. Not so often now of course, but several a week, > back in the day ...   > Arfa   Some of the higher-end Aiwa decks were the worst. In addition to the mechanics - there was a cluster - f**k of hard wiring to work around.   Mark Z.

N_Cook <diverse@tcp.co.uk>: Jun 03 04:26PM +0100 On 03/06/2015 13:35, Mark Zacharias wrote:   > Some of the higher-end Aiwa decks were the worst. In addition to the > mechanics - there was a cluster - f**k of hard wiring to work around.   > Mark Z.   Ah the feindish Aiwa AD 6900 lump from 1970s, just. Someone wanted me to repair one 2 months back , via post, until he found what 2 lots of postage would be.

Andre Majorel <cheney@halliburton.com>: Jun 03 08:13AM Found in a yoghurt maker whose heating element never turns off :   http://www.teaser.fr/~amajorel/ee/f/ti3070s2.jpg   Black plastic, 23.3 x 6.7 x 3.6 mm with two wires (red and black) coming out of one end. Marked TI-30 70 S2.   Judging by the shape, it could be a thermocouple or an RTD. Does anyone know what it is ?   Thanks in advance !   -- André Majorel http://www.teaser.fr/~amajorel/ It is difficult to get a man to understand something, when his salary depends upon his not understanding it. -- Upton Sinclair

N_Cook <diverse@tcp.co.uk>: Jun 03 12:16PM +0100 On 03/06/2015 09:13, Andre Majorel wrote:   > Judging by the shape, it could be a thermocouple or an RTD. Does > anyone know what it is ?   > Thanks in advance !   looks like one of those compact bimetal dome switches, try heating wiht a hot air gun connected to DVM-R

micky <NONONOmisc07@bigfoot.com>: Jun 02 10:04PM -0400 How much power is used by the final stage?   Got a new Sandisk Clip, a very small MP3 player with an FM radio.   Built in battery, recharges from USB. I will probably forget to do this.   Am I correct, about radios in general and probably about this, that 80 or 90% of the power is used in the last stage, the stage that powers the earbuds (or the speakers in a radio) And t hat all the other stages put together use less than 10 or 20% of the power?   Sometimes when listening to the radio and walking around, the sound disappears because the signal is not there. No hum even. Am I right that it's only using 10 or 20% of the power it does when the program is playing?   Thanks a lot

Michael Black <et472@ncf.ca>: Jun 02 11:06PM -0400

Phil Allison <pallison49@gmail.com>: Jun 02 09:05PM -0700 micky wrote:   > How much power is used by the final stage?     ** How long is a piece of string ?     > Am I correct, about radios in general and probably about this, that 80 > or 90% of the power is used in the last stage, the stage that powers the > earbuds (or the speakers in a radio)     ** Ear buds use FAR less power than speakers, less than 1 milliwatt at ordinary listening levels. The other circuitry is likely using way more.     > disappears because the signal is not there. No hum even. Am I right > that it's only using 10 or 20% of the power it does when the program is > playing?   ** No.   Got any more boring, silly questions ?     .... Phil

Chuck <chuck@mydeja.net>: Jun 02 06:10PM -0500 On Tue, 2 Jun 2015 07:29:10 -0700 (PDT), John-Del <ohger1s@aol.com> wrote:   >> > My vintage Sony Trinitron model KV-19TS20 goes wacky after inly a few seconds. screen has jagged lines and makes a noise that changes in pitch from low to high. Can somebody please help me?   >> Tuner grounds? You may be thinking of RCA   >Sony tuners were not immune to bad grounds, particularly the combo tuner/IF modules, although they were no where as troublesome as those RCA CTC17X series.   At the Sony warranty station where I worked there were so many sets returning with tuner ground failures, that it got to the point, regardless of what the set was brought in for, we resoldered the tuner grounds as well as all IF and AFT transformer leads.   --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com

captainvideo462009@gmail.com: Jun 02 11:34AM -0700 I presently have two old, (PRC77's for whoever may be familiar with these), ex military portable FM back pack radios on the bench that I'm checking out. These units tune 950 channels between 30 and 75 MHZ and output between one and two watts depending on frequency. Admittedly these circa 1968 radios are no longer very practical, but fun to put on six meters and bring to Ham fests. The radios operate on 14.4 volt battery packs.   The old magnesium battery packs were dead so I removed the special connectors from them, soldered 9.0 foot 14 AWG. leads on them and connected these to two bench power supplies. I was trying to measure the voltage and note the current during transmit. I had my 265 set to the 60.0 volt range and connected at the power supply. The power supplies were both set to 14.0 volts as noted on my meter. Every time I keyed the transmitter the meter reading dropped to slightly below zero. At first I thought that the power supplies might be current limiting but that didn't make sense because the squelch remained open, clearly indicating the presence of a carrier on the scanner.   I tried a portable digital as well as my bench Fluke. The portable dropped to 4.80 volts and the fluke's power supply, (apparently) for whatever reason broke the squelch on my scanner, so I wasn't able to use that meter at all. Interestingly the only meter that was "almost" impervious to the anomaly was my old RCA Senior Voltohmyst. The meter fluttered very slightly but remained pretty steady. I seem to recall in the specs for that meter that the upper limit was something like 3.50MHZ.   Finally in desperation I connected my scope using a X1 probe up in place of the meter and confirmed the presence of an RF carrier superimposed on the DC level every time I keyed. I tried using "HF REJ" on the scope hoping that would eliminate the carrier but surprisingly it made no difference.   So I built a small PI filter comprised of two small chokes and a small capacitor, values unknown at this point. The configuration is as follows: Each lead of the scope is in series with a choke, then the cap is across the other side of the two chokes, and the line then goes to the radio, and then the power supply.   This filter decreased the RF displayed on the scope considerably but when switched over to the 265, not enough to effect the problem with it very much. However when this filter was placed ahead of the Senior Voltohmyst there were no anomalies present on it. Yay for old technology!   So this is not a huge problem. I don't mind using my RCA meter with my make shift filter to read this voltage. But then in theory to use my other equipment such as the scope it would seem like I need to design a filter having a resonant frequency equal to every frequency I want to check. That's not very practical.   I woud reall appreciate any further thoughts on this. Thanks, Lenny

dplatt@coop.radagast.org (Dave Platt): Jun 02 12:42PM -0700 In article <b8ba0a30-f890-41f8-9d5b-ee95f2baa9ed@googlegroups.com>,   >I woud reall appreciate any further thoughts on this. Thanks, Lenny   Were you actually transmitting (through an antenna) during these tests?   If so, does the problem recur if you install a proper RF dummy load in place of the whip antenna?   My guess is that when you transmit through a whip, the whole chassis is going to be RF-hot (it's the "ground" or "counterpoise" side of the antenna system), and a lot of the RF is going to propagate back down the power cables. There's likely to be enough RF getting into the metering electronics (whether digital or analog) to cause rectification in diodes/transistors in the measurement circuitry... hence the rather bogus readings you're getting.   An old-style "hot wire" ammeter might be your best bet for evaluating DC current draw in this situation.

captainvideo462009@gmail.com: Jun 02 03:02PM -0700 > This filter decreased the RF displayed on the scope considerably but when switched over to the 265, not enough to effect the problem with it very much. However when this filter was placed ahead of the Senior Voltohmyst there were no anomalies present on it. Yay for old technology!   > So this is not a huge problem. I don't mind using my RCA meter with my make shift filter to read this voltage. But then in theory to use my other equipment such as the scope it would seem like I need to design a filter having a resonant frequency equal to every frequency I want to check. That's not very practical.   > I woud reall appreciate any further thoughts on this. Thanks, Lenny   The 77's have a BNC jack on the top panel as well as a threaded mount for either a short or long whip antenna. At the time I had my watt meter connected to the BNC jack with a dummy load off the other side of that. However I did have the whips installed on both radios. I didn't want to key without an antenna in place, but that probably wasn't necessary since I had the dummy load on there. I'll repeat everything with the antennas removed and report back. Thanks. Lenny   https://www.google.com/search?q=prc77&tbm=isch&tbo=u&source=univ&sa=X&ei=lyZuVdmdGY-1sQTbjYGoBA&ved=0CB4QsAQ&biw=1024&bih=615#imgrc=53bT9hnw-U_VPM%253A%3BWVuMYSHaxTgw2M%3Bhttp%253A%252F%252Fwww.prc68.com%252FI%252FImages%252FPRC77-02b.jpg%3Bhttp%253A%252F%252Fwww.prc68.com%252FI%252FPRC77.shtml%3B1280%3B557

Cydrome Leader <presence@MUNGEpanix.com>: Jun 02 09:38PM > I have installed a thermostat in my garage to control a fan placed on a shelf in front of the peak vent. The thermostat box has a 6V AA battery pack which switches control voltage to SS relay near the fan. The relay says "Silicon Power Cube" on it and is rated for 240V and 3A. I am using it on 120VAC. The control voltage is specified at 3 to 32 VDC. This system works perfectly. I have been using common 20 inch box fans. The problem is they only last a year or so and then they just stop working. Sometimes they fail over the winter when they never run. I have tried to troubleshoot the fans but can't find out why they have failed. The capacitors on the motor measure the correct value. I suspect there is something in the SS relay that is causing them to fail but I have no idea how. Are SS relays compatible with induction motors? I am on my fourth fan in about 5 years now and these fans usually last forever. > Thanks for any ideas. > Soartech   You might try a name brand solid state relay and see what happens. Crydom is real, silicon cube is not.

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