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"pfjw@aol.com" <peterwieck33@gmail.com>: Jul 25 12:27PM -0700 We have established that you cannot read for content. No, we do not install GFCI devices throughout the house. Where they are either necessary-by-code or just a good idea, we use the CIRCUIT BREAKER combination device. Then, it becomes that super-fast circuit-breaker.   I do not know if the higher-end devices have built-in snubbers - I do know that we are generally free of nuisance trips. As to motors, our hot-tubs are each fed with a 50A device that is about 30% larger than a standard double-pole unit, and feeds to a common neutral- ending that myth. The pump is 120V, the blower is 120V, the heater is 240V @ 5,000 watts. So, depending on what is going at any given time, the load is simply not balanced.   All of our devices are damp-location rated, figuring it cannot hurt, and the premium is minimal.   Kids, grandkids, cats, dogs, and all the parts-and-pieces thereto. Makes these sorts of choices pretty basic and pretty obvious.   Peter Wieck Melrose Park, PA

makolber@yahoo.com: Jul 25 12:37PM -0700 > All of our devices are damp-location rated, figuring it cannot hurt, and the premium is minimal.   there is a good point.   I think there are GFI's that are calibrated for a little higher trip current.   Those might be worth a try.   m

tabbypurr@gmail.com: Jul 25 04:50PM -0700 > the answer I'll try it and if new, higher quality GFCIs work then that > will be great and the question answered. > Eric   Snubbers are the obvious option to try. 0.1uF + 100R in series absorbs hf content so the gfci doesn't see much of it.     NT

Fox's Mercantile <jdangus@att.net>: Jul 25 07:55PM -0500 > Snubbers are the obvious option to try. 0.1uF + 100R in series > absorbs hf content so the gfci doesn't see much of it.   And in case it isn't obvious, that series combination is across the AC line. Not on the switched side of the load.     -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

bruce2bowser@gmail.com: Jul 25 08:46PM -0700 > We have established that you cannot read for content. No, we do not install GFCI devices throughout the house...   Unless the house is still under construction =============================================== DATES GFCI REQUIREMENTS WERE ESTABLISHED ([NEC]:   1971 Receptacles within 15 feet of pool walls 1971 All equipment used with storable swimming pools 1973 All outdoor receptacles 1974 Construction Sites :   -- https://www.nachi.org/forum/f19/gfcis-code-changes-history-chart-12234/

"pfjw@aol.com" <peterwieck33@gmail.com>: Jul 26 04:15AM -0700 > On Wednesday, July 25, 2018 at 3:27:27 PM UTC-4, pf...@aol.com wrote: > > We have established that you cannot read for content. No, we do not install GFCI devices throughout the house...   > Unless the house is still under construction   Our house was built in 1890, with substantial additions added in 1928.   Peter Wieck Melrose Park, PA

Jeff Layman <jmlayman@invalid.invalid>: Jul 25 09:48PM +0100 On 23/07/18 20:27, N_Cook wrote: > bulbs are flattened rather than spherical , because depite the > reputution of German design being so great , they cocked up and the lid > would not close with the original intended bulbs, without breaking them.   A late reply, but I had to ask someone who had worked on repairing an Enigma machine about this. I am afraid your idea that the design was fault is not correct. The real explanation can be found here <http://www.cryptomuseum.com/crypto/enigma/lamps.htm>   --   Jeff

N_Cook <diverse@tcp.co.uk>: Jul 26 08:30AM +0100 On 25/07/2018 21:48, Jeff Layman wrote: > Enigma machine about this. I am afraid your idea that the design was > fault is not correct. The real explanation can be found here > <http://www.cryptomuseum.com/crypto/enigma/lamps.htm>   "flattened lamps that are required for the Enigma." If they had allowed more space, to recess the bulb holder deeper, then no requirement for flattened bulbs. But discoloured windows rather than broken bulbs would have been the result of the design error, it seems. As E and T are single dits or dahs, there is presumably a Morse connection with this 24 character alphabet, but no further foreward as to why or what for.

Jeff Layman <jmlayman@invalid.invalid>: Jul 26 09:45AM +0100 On 26/07/18 08:30, N_Cook wrote: > As E and T are single dits or dahs, there is presumably a Morse > connection with this 24 character alphabet, but no further foreward as > to why or what for.   Well, the article does hedge its bets a bit. This is the start of the first paragraph: "An Enigma machine has small - rather unusual - lamps on its lamp panel."   And this the start of the second: "Lamps like these were rather common before and during WWII"   So are they "rather unusual" or "rather common"?!   Can't help you with the E and T issue, but you might be right about the Morse connection. It might be worth looking through the "Popular cipher machines" at <http://www.cryptomuseum.com/crypto/index.htm> to see if any of the keyboards match.   --   Jeff

N_Cook <diverse@tcp.co.uk>: Jul 26 10:26AM +0100 I find the fluting business equally intriguing, perhaps a bit like military connectors MIL-DTL-38999 ? series . Bakelite , but perhaps similar reasoning, that only certain patterns of fluting will mate male and female and correct indexing. These key "caps" must have fitted into some sort of matrix of "coded" patterned recesses, rather than projecting upwards on levers like a typewriter/teleprinter.

captainvideo462009@gmail.com: Jul 25 06:38PM -0700 This is somewhat of an off topic question but it does pertain partially to my 77. I recently bought at auction a 2010 Dodge Charger which was a former New Hampshire state police car. There are three holes, One hole is in the center of the roof. Another is further back about two inches from the top of the rear windshield, and the last one is in the center of the trunk. They look like the type of holes that would be cut out for mounting NMO bases.   This is actually very convenient because I have a low band (around 42MHZ } business radio, and a Yaesu FT857 mobile radio with a DTMF microphone. I would like to use the Yaesu on both 2 and 6 meters, and I would also like to make provisions for using one of my PRC77's on 51MHZ from time to time as well.   So I want to install three antennas on the car. These would all be NMO type quarter wave base loaded whip antennas. The configuration I considered is as follows: The 42MHZ antenna would be in the center of the roof The six meter whip would be behind it and the 2 meter antenna would be on the trunk. I figured if I'm not using the 77,(which would probably be a good portion of the time) I can AB switch the six and two meter antennas into the Yaesu.   I'm not interested in having the best antennas on my car. I already have the bases, cables, and whips to do all this. I wouldn't have to buy anything. I just want to have a little Ham fun with them while keeping my business communications intact as well. And of course I need to fill the holes...Does it seem like the antennas might interfere with one another? Thanks, Lenny, KC1CPX

Terry Schwartz <tschw10117@aol.com>: Jul 25 08:10PM -0700 If the antennas end up at least 12" from each other, there should be no interference or de-tuning.

makolber@yahoo.com: Jul 25 01:07PM -0700 So, if you parallel a mess > of capacitors to make a run capacitor with the correct value for PF=1, > then the capacitors will dissipate zero power.   not true. if there is current flowing through the cap, ESR of the cap will dissipate power. The purpose of a motor cap is not to correct the PF.   There is no such thing as a single phase motor. Small motors have shaded poles or other tricks to create a phase shift. Medium size motors motors use a cap. Large motors are typically fed with 3 phase.   I think the optimum cap value, is where the current through the aux winding is 90 deg out of phase with the main winding. m

Jeff Liebermann <jeffl@cruzio.com>: Jul 25 03:23PM -0700 >> of capacitors to make a run capacitor with the correct value for PF=1, >> then the capacitors will dissipate zero power.   >not true.   I agree. I screwed up and forgot about ESR.   >Small motors have shaded poles or other tricks to create a phase shift. >Medium size motors motors use a cap. >Large motors are typically fed with 3 phase.   Also true. However, the original problem is with a 3HP motor, with no run capacitor. I guess for high torque starting, such as with an air compressor, this would be an exception.   >I think the optimum cap value, is where the current through the aux >winding is 90 deg out of phase with the main winding.   Agreed. This explains it better than I could: <https://www.quora.com/What-is-a-capacitor-start-capacitor-run-in-a-motor>         -- 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

captainvideo462009@gmail.com: Jul 25 01:01PM -0700 On Friday, July 20, 2018 at 10:10:32 PM UTC-4, John-Del wrote: > Fisher RS-717 with water damage. Guy wants it fixed for nostalgia's sake...   > John   John What happens if you look at the discriminator output? What if you switch to FM mono? Maybe there is a circuit right after that output that "preamplifies the demodulated signal before it gets to the common audio circuits? Lenny

John-Del <ohger1s@gmail.com>: Jul 25 12:35PM -0700 On Tuesday, July 24, 2018 at 4:09:38 PM UTC-4, Ian Field wrote: > Someone here seems much better at finding service manuals than me.   > AFAICR: its just a web page with a well hidden button to download it.   > Thanks for any help.   You might be thinking of:   https://elektrotanya.com/   But I doubt Sony ever produced a service manual for such a cheap item. They're on ebay in the $20 range.

captainvideo462009@gmail.com: Jul 25 12:30PM -0700 > This radio had an open speaker field coil. I subbed a choke from my junk pile in place of the coil and used a PM magnet speaker. I have no idea what the specs on the OEM field coil were or those of the choke for that matter. I just grabbed something to try. The choke is about half the size of a baseball if that makes any sense. The choke came out of something God only knows what and how long ago and measures about 40 ohms. The filter, a three section twenty UF, two at 450V and one at 25 volts was replaced at some point and seems to be OK. I mention this because there is a very slight hum out of the speaker and I'm thinking that perhaps the elimination of the hum bucking coil in the OEM speaker is the cause of this. The hum isn't that bad. as soon as you turn the volume up a bit it's really not noticeable but without using another electro dynamic speaker can I do anything about this? I'm also wondering if I sized the choke properly. Does anyone have any thoughts on these two concerns? Thanks, Lenny   Thanks for all the great ideas guys. I did get it going but it needs an alignment particularly on the short wave band. Lenny

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