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avagadro7@gmail.com: Jul 28 04:35PM -0700 > http://www.bcae1.com/relays.htm   https://goo.gl/TCo6MH

Deane Williams <pyroartist.dw@gmail.com>: Jul 29 08:12AM -0700 > motor isn't overheating.   > Does the fan still spin? Is there continuity in the winding?   > John :-#)#   The motor still spins easily. There is no DC continuity from the power plug but I beleive this is normal for induction motors? Perhaps the overheat sensor has opened permenently. Home Depot gave me a replacement so I will try it again. These fans typically last for many years when plugged directly into a wall socket. This is a real mystery to me. Perhaps SS relays generate some large spikes on their output? I should check it with a scope. Thanks for the comments.

Deane Williams <pyroartist.dw@gmail.com>: Jul 29 08:13AM -0700 On Tuesday, July 28, 2015 at 3:15:20 AM UTC-4, N_Cook wrote: > > Thanks for any ideas. I am going to switch over to a mechanical relay.   > > Dean   > Do you do TIG/MIG welding in this garage?   No. I don't own a TIG/MIG welder.

Deane Williams <pyroartist.dw@gmail.com>: Jul 29 08:14AM -0700 > http://www.bcae1.com/relays.htm   Thanks for the detailed treatise on mechanical relays. But I am using a solid state relay (SSR).

"J.B. Wood" <arl_123234@hotmail.com>: Jul 29 08:24AM -0400 On 07/27/2015 02:51 PM, Jeff Liebermann wrote: > contact surfaces with vaseline so that you can take it apart. Fill > the mold with your favorite rubber compound (I used hard automotive > RTV) to clone the part. Clean up the flashing with an Xacto knife.   Thanks, for the detailed info, Jeff. I wouldn't have guessed how to make new rubber retainers/bumpers. Folks who restore pinballs and jukeboxes probably know this stuff. Sincerely, -- J. B. Wood e-mail: arl_123234@hotmail.com

N_Cook <diverse@tcp.co.uk>: Jul 29 09:03AM +0100 PMH1000 schematic is very similar, 2 zener drop per ch, 2 SMPS ICs the same etc I didn't bother checking the pots function as 4 pots would not fail in the same manner - wrong. Logo B in a triangle, blue body, marked 05 C5 02 on the underside. Very iffy resistance at both ends of the track. Used here as simple variable resistors,wiper tied to min gain end , max gain at zero ohms position. 5K Log track, mid track 300R, but last mm or so jumps from roughly 100R to 0R, similar the other end. Last 3/4mm or so very irregular resistance Took apart and cleared out the grease, same patchy response on reassembly. I don't think its wear as all pots the same at both ends (min gain end does not matter here in use as imperceptible). Perhaps the grease reacts with the track surface , scraping back the track surface , seems to make the situation worse. Same patchiness on the part of the track not swept by the wiper. Main problem was perhaps SMPS going into protect, or "digital amps" goung into protect ,as unusually amp was used outdoors in sunshine or failure of a PA-Prea insert switch if one channel failed

Jeff Liebermann <jeffl@cruzio.com>: Jul 28 06:44PM -0700 >> cooling (something more than mere heat sinks and fans, IOW).   >> Many thanks.   >2) only if you know the current carrying capacity of their winding wire   Nope. A fuse works by heating the wire high enough to where the wire oxidizes and turns into an metallic oxide which then crumbles. If you can extract the heat from the wire to maintain a temperature below this point, the fuse will last indefinitely. Dumping the load resistor into a bucket of water does this quite nicely. To do this, the wire is in intimate contact with a refractory ceramic which then transfers the heat to a metal case and finally to the water. No air gaps allowed.   You can demonstrate the principle with a common coffee cup heating coil: <http://www.ebay.com/itm/171376872247> If you bypass the internal thermostat and run it in open air, it will blow up rather quickly. However, if you immerse it in water, the water will conduct most of the heat away, thus preventing the heater wire from fusing.   -- 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

"Ralph Mowery" <rmowery28146@earthlink.net>: Jul 28 11:11PM -0400 "Phil Allison" <pallison49@gmail.com> wrote in message news:0c799d3c-9477-4076-b521-a6a8a6bd7410@googlegroups.com...   >> or other odd ball waveforms   > ** An audio amplifier reproducing a square wave will not pass harmonics > much above 50kHz top the load - so you are wrong again.   Do try and keep up. This is about the output of the amplifier. It does not mater what the amp is going to pass.   From a quick test with a couple of wire wound resistors an audio frequency square wave was producing a spike on the leading and trailing edges of the ww resistor. It did not do that with a carbon resistor.

Phil Allison <pallison49@gmail.com>: Jul 28 09:39PM -0700 Ralph Mowery wrote:   > > much above 50kHz top the load - so you are wrong again.   > Do try and keep up. This is about the output of the amplifier. It does not > mater what the amp is going to pass.   ** Huh ????   Since amplifiers cannot pass the harmonic frequencies, they will NOT appear at the output.     > From a quick test with a couple of wire wound resistors an audio frequency > square wave was producing a spike on the leading and trailing edges of the > ww resistor.   ** An "audio frequency square wave" must have its harmonics filtered out above the audio band.   However, what you have is a *WIDE BAND* square wave with its fundamental at an audio frequency.   I understand your test and a similar one to compare low value WW resistors for such inductance. Normally you see overshoot and ringing at frequencies in the low MHz range on the scope - using a 100kHz square wave.       ... Phil           ... Phil     It did not do that with a carbon resistor.

"Ian Field" <gangprobing.alien@ntlworld.com>: Jul 28 07:20PM +0100 Recently my Philips coolshave started not giving many shaves per charge - as luck would have it, I'd just salvaged a pack of 1000mAh Ni-Cd cells (Ni-Mh that I have bags of won't do) from some scrap equipment.   Since it was apart anyway, the connections from the charging plug were more easily accesible than the holes in the charger plug, so I grabbed the DMM - 25VDC charger for a single 1.2V cell.   Would anyone care to offer comments on the likely rationale of that?   Thanks.

John Robertson <spam@flippers.com>: Jul 28 02:05PM -0700 On 07/28/2015 11:20 AM, Ian Field wrote: > the DMM - 25VDC charger for a single 1.2V cell.   > Would anyone care to offer comments on the likely rationale of that?   > Thanks.   Might be the unloaded voltage.   High voltage but very low current might be good for keeping the whiskers from building up inside the cells. not that I know for sure, simply a guess.   What is the voltage when you plug it into the battery pack?   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."

"Ian Field" <gangprobing.alien@ntlworld.com>: Jul 28 10:12PM +0100 "John Robertson" <spam@flippers.com> wrote in message news:AtmdnY6DsZ6LcirInZ2dnUU7-IOdnZ2d@giganews.com... > from building up inside the cells. not that I know for sure, simply a > guess.   > What is the voltage when you plug it into the battery pack?   As I explained - it was easier to get at the connections while the shaver was open and taking a reading from the terminals inside.   The charger was plugged into the shaver when I measured it.

John Robertson <spam@flippers.com>: Jul 28 02:49PM -0700 On 07/28/2015 2:12 PM, Ian Field wrote:   > As I explained - it was easier to get at the connections while the > shaver was open and taking a reading from the terminals inside.   > The charger was plugged into the shaver when I measured it.   No better idea other than it would appear that the ni-cad battery is open, otherwise it would load that down and possibly get rather warm if there is any current available.   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."

dplatt@coop.radagast.org (Dave Platt): Jul 28 05:22PM -0700 In article <UeStx.44972$3n4.31287@fx35.am4>,   >As I explained - it was easier to get at the connections while the shaver >was open and taking a reading from the terminals inside.   >The charger was plugged into the shaver when I measured it.   Could it be that the charging circuit is a buck regulator? The feed from the wall wart could be "higher voltage, lower current", which would result in lower losses the wire.

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