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Cydrome Leader <presence@MUNGEpanix.com>: Apr 03 05:45PM >> Peter Wieck >> Melrose Park, PA > Good find! I haven't seen those in years. I forgot about Philmore making them.   Forgot about those too. You used to be able to pick them up at radio shack.

John Robertson <spam@flippers.com>: Apr 03 11:32AM -0700 On 2021/03/28 4:16 a.m., Peter W. wrote:   > For those of us who have the awful habit of restoring vintage equipment with non-polarized convenience receptacles and who often have a hard time finding replacements - These fit Dynaco and similar products.   > Peter Wieck > Melrose Park, PA   Interesting, I have many NOS ones that I picked up from a Philmore distributor. Guess I should put them up on my web site...but they will be more than $1 as I think these are actually UL/CSA approved.   John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3 (604)872-5757 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

"Peter W." <peterwieck33@gmail.com>: Apr 04 04:09AM -0700 Guess I should put them up on my web site...but they will > be more than $1 as I think these are actually UL/CSA approved.   John:   As these would never be stand-alone devices, they should carry a UR (with the R reversed) designation. And, yes, that would be handy.   Peter Wieck Melrose Park, PA

Cydrome Leader <presence@MUNGEpanix.com>: Apr 03 06:34PM > U need an isolated ground receptacle. Used to combat noise interference with audio and video, it must be supplied by a metal raceway or cable system that is an equipment grounding conductor. Connect it past any panelboards and absolutely do not connect it to the panelboard grounding terminal bar, but to independent 3 x 6 ft. independent copper rods completely driven into the ground.   > (As per code NEC 517.16 Use of Isolated Ground Receptacles > "The grounding terminal on the isolated ground receptacle must be connected by an insulated equipment grounding conductor with one or more yellow stripes which is permitted to pass through one or more panelboards without a connection to the panelboard grounding terminal bar as permitted in 408.40 ...)   why would a ceiling fan plug into a receptacle? This suggestion is just dumb.   There's no harm in trying a filter, but checking the quality of your grounding also doesn't hurt, make sure neutral and hot are not reversed etc. It still just sounds like a cheaply made motor drive.

Jeff Layman <jmlayman@invalid.invalid>: Apr 04 08:59AM +0100 On 03/04/2021 19:34, Cydrome Leader wrote:   > There's no harm in trying a filter, but checking the quality of your > grounding also doesn't hurt, make sure neutral and hot are not reversed > etc. It still just sounds like a cheaply made motor drive.   That's the first time I've had an old post resurrected by Google Groups! :-)   My OP was over 6 years ago. FWIW the interference was stopped by using a delta suppression filter and a ferrite ring.   --   Jeff

"jurb...@gmail.com" <jurb6006@gmail.com>: Apr 03 07:17PM -0700 >DC on both meters on lowest range, 20 V.   AHA, the keystone part of the puzzle. This blows Phil's statement out the water which is rare, there is no TRMS in DC.   Now you are down to the meters being plain old wrong, after all one just be, right ?   First of all realize that 100% LED compatible dimmers, which could be used on multiple lights must be the raw PWM. ON OFF ON OFF. If you smooth it off the a DC voltage, LEDS in parallel might fire at slightly different voltages and screw ya all up. So PWM is fine with LEDs as long as you never exceed the Imax (current rating) As such your meters on DC are actually measuring AC in the wrong mode.   It will help to know how the digital voltmeter works. Now when a voltage is applied to a DVM it is of course divided by the range control and whatever. After that it goes to a comparator. The other input to the comparator is a sawtooth wave, generated quite accurately. When your input voltage and the voltage from the sawtooth cross, the comparator changes states and puts out an output. The exact time that happens is used to stop or read a counter to know just how much the internal voltage has risen.   It is easy to see that each DVM can have its own timing, or speed. higher speeds read faster and they are more expensive if they are accurate.   Now if you want a DC measurement, which could be useful, then you must feed the meter DC, not AC. As you can see frigs it all up. So, an extremely simple way would be to get like a 5K resistor and like a maybe what guys, 68uF ? Take the resistor from the output, connect it and the probe there, and the cap and the other end of the cap to ground. yyou just made an R/C filter. This should make the meters read the same.   That is because they are measuring DC on the DC range.   I can't remember when the last time it was I had to make an R/C filter like that but I know I did a couple of times.

Phil Allison <pallison49@gmail.com>: Apr 03 07:43PM -0700 jurb...@gmail.com wrote: ====================   > AHA, the keystone part of the puzzle. This blows Phil's statement out the water which is rare, there is no TRMS in DC.   ** FYI:   " true RMS " = DC equivalent value for the *heating* effect on a resistance.   Repeating waveforms may have a DC offset = average DC value.   The "true RMS" value of such wave is:   sqrt ( DC ^2 + ACrms ^2 )       ..... Phil

KenW <ken1943@invalid.net>: Apr 03 03:28PM -0600 Why play around return the thing. The next time don't put the blades on and wire it to a plug, plug it in and test.     KenW

KenW <ken1943@invalid.net>: Apr 03 03:29PM -0600 Also check online for problems with the model you got.     KenW

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