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"Tom Del Rosso" <fizzbintuesday@that-google-mail-domain.com>: Jan 12 06:43PM -0500 I expect a large fridge to draw around 5 amps, but my clamp transformer (on one wire of a broken-out extension cord of course) and Fluke together say 830ma when the thing is running. Does that seem wrong? It measures the toaster oven at 9.1A and the fridge light at 300ma.     --

amdx <nojunk@knology.net>: Jan 12 06:04PM -0600 On 1/12/2020 5:43 PM, Tom Del Rosso wrote: > (on one wire of a broken-out extension cord of course) and Fluke > together say 830ma when the thing is running. Does that seem wrong? It > measures the toaster oven at 9.1A and the fridge light at 300ma.   Are sure that is not just a fan running without the compressor running? It has to be more when the compressor runs.   Mikek

Michael Terrell <terrell.michael.a@gmail.com>: Jan 12 04:05PM -0800 On Sunday, January 12, 2020 at 6:43:33 PM UTC-5, Tom Del Rosso wrote: > (on one wire of a broken-out extension cord of course) and Fluke > together say 830ma when the thing is running. Does that seem wrong? It > measures the toaster oven at 9.1A and the fridge light at 300ma.     That sounds about right. A refrigerator maintains a low temperature, but takes a long time to pull the contents down from room temperature. The compressor is tiny, inside the housing It is spring mounted to reduce the noise, and to surround the motor with refrigerant. If it drew 9.1A, that would be over a Kilowatt that would need to be dissipated, along with the interior heat.

Jeff Urban <jurb6006@gmail.com>: Jan 12 04:41PM -0800 We measured a new fridge at the store, had to talk the manager into it but I built a box with a cord and outlet and a wire looped outside for a clamp on ammeter.   We got a peak of like 9 amps or so to start but then it went be;ow one amp.   However if the thing has not been in service the condenser is not pressurized which does make the compressor draw more. We didn't want to hang around all day so we took the data and went on to other things. This was for a solar powered camper made out of a box truck.   The trend now is for a smaller refrigeration system that runs longer. The peak at startup is one issue but there are so many others. Manufacturing costs, weight/freight. It all needs to be considered when you make decisions like that in design.   There are drawbacks. I would bet real money that if you put a new and old fridge out on 100º in the sun the old one could cool the food but the new one would not. But how many people are going to do that ?   So you might have 80 watts for 6 hours but with an old one you would have 160 watts for 3 hours. The lower drain means less loss of power in the house wiring, and not contributing as much to peak demand.   Thing is, after the startup surge, take and run the thing for a couple hours with the doors open. Then you get a worst case scenario value for its current drain.

"Tom Del Rosso" <fizzbintuesday@that-google-mail-domain.com>: Jan 12 09:04PM -0500 Jeff Urban wrote: > for a clamp on ammeter.   > We got a peak of like 9 amps or so to start but then it went be;ow > one amp.   Thanks to all. This is good, so I can put some other loads on the fridge outlet.

danny burstein <dannyb@panix.com>: Jan 13 02:58AM >> one amp.   >Thanks to all. This is good, so I can put some other loads on the >fridge outlet.   Maybe, maybe not.   While typical refrigerators these days pull one amp (or less...) while running, the "frost free" ones use a hell of a lot more during the defrost cycle.   I've measured _500_ watts (4 amps) on mine.   A meeting hall I work with had a problem where the circuit breaker feeding the overhead lights would overload and open up, plunging the room into darkness.   Which made no sense. Yes, I re-measured the load and swapped breakers...   On checking further, I found that they had added an outlet which was slaved off the lighting circuit [a] and was being used for a refrigerator.   It took some head scratching before I realized that when the lights were on at the same time the refrigerator went into defrost mode, the power draw exceeded the breaker rating.   Since the place was rarely used, just about all the time the defroster kicked in the lights were off, so these blackouts were few and far between...   [a] installed by a professional and licensed electrician who should have known that Code does NOT like appliance outlets on lighting circuits for exactly this reason.     -- _____________________________________________________ Knowledge may be power, but communications is the key dannyb@panix.com [to foil spammers, my address has been double rot-13 encoded]

Jeff Liebermann <jeffl@cruzio.com>: Jan 12 08:30PM -0800 On Sun, 12 Jan 2020 18:43:28 -0500, "Tom Del Rosso" >(on one wire of a broken-out extension cord of course) and Fluke >together say 830ma when the thing is running. Does that seem wrong? It >measures the toaster oven at 9.1A and the fridge light at 300ma.   Make and model of the fridge? 117VAC or 240VAC? I can possibly lookup the expected current drain online and do a sanity check. I found a few charts that claim a full size refrigerator/freezer should draw about 700 watts. 5A sounds about right: 117VAC * 5A = 585 VA No clue on the PF (power factor) so I'll use VA instead of watts.   If you're seeing only 0.83A, then you're looking at the current drawn by a fan or light bulb in the fridge, not the compressor. Try lowering the temperature setting of the thermostat temporarily to force the compressor to start.   -- 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

"Tom Del Rosso" <fizzbintuesday@that-google-mail-domain.com>: Jan 12 11:47PM -0500 Jeff Liebermann wrote: > lookup the expected current drain online and do a sanity check. I > found a few charts that claim a full size refrigerator/freezer should > draw about 700 watts. 5A sounds about right:   Frigidaire FFHT1621TS1     > by a fan or light bulb in the fridge, not the compressor. Try > lowering the temperature setting of the thermostat temporarily to > force the compressor to start.   Tthat 800ma is when it's making noise. It's less than 10ma the rest of the time. The other loads are toaster and microwave so they draw zero most of the time.   The most unfortunate thing is that all the outlets in the kitchen seem to be on one breaker. I say so because there is a 3 volt drop on any outlet when the toaster oven draws 9 amps. In another room it drops 100mv or less.

"Tom Del Rosso" <fizzbintuesday@that-google-mail-domain.com>: Jan 13 12:02AM -0500 danny burstein wrote: > while running, the "frost free" ones use a hell of a lot > more during the defrost cycle.   > I've measured _500_ watts (4 amps) on mine.   That might be a few times a day but my other loads are used even less often. The total is still under 15 amps which is what motivated me to measure it.

gregz <zekor@comcast.net>: Jan 13 07:29AM >> one amp.   > Thanks to all. This is good, so I can put some other loads on the > fridge outlet.   Newer ones seem to draw less on auto defrost. I think some older ones may draw a bunch, like 10 amps or more.   Greg

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Jan 12 03:21PM -0500 On 2020-01-12 09:36, Cursitor Doom wrote: > this purpose? A DSO, maybe? Or if not, optimising the settings on the > analogue scope to have the best chance of spotting them? > thanks!   Finding an asynchronous glitch is hard on an analog scope.   Cheers   Phil Hobbs   -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510   http://electrooptical.net http://hobbs-eo.com

Cursitor Doom <curd@notformail.com>: Jan 12 09:36PM On Sun, 12 Jan 2020 15:21:39 -0500, Phil Hobbs   >Finding an asynchronous glitch is hard on an analog scope.   It is to a major extent reproduceable, though, Phil. I can manually override the ramp and set a voltage which will show up a glitch in the frequency domain, which is a useful plus. You reckon it would be better to use a DSO for this? I do have one. --   No deal? No problem! :-D

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Jan 12 05:17PM -0500 On 2020-01-12 16:36, Cursitor Doom wrote: > override the ramp and set a voltage which will show up a glitch in the > frequency domain, which is a useful plus. You reckon it would be > better to use a DSO for this? I do have one.   Frequency domain glitch? You mean a discrete spur?   A glitch is a transient time-domain animal. A DSO can save a single instance, or (with averaging) ignore the noise and asynchronous background and just reproduce the glitch itself.   Cheers   Phil Hobbs   -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510   http://electrooptical.net http://hobbs-eo.com

Jeff Liebermann <jeffl@cruzio.com>: Jan 12 02:22PM -0800 On Sun, 12 Jan 2020 14:36:27 +0000, Cursitor Doom >recently. The problem *seems* to be noise spikes on the DC voltage >control ramp which are causing spurious spikes in the frequency domain >on the RF output when viewed on an RF spectrum analyser.   In other words, it's picking up garbage from something in your shop (or cave). I suggest you start by moving or removing all the switching power supplies, wall warts, light dimmers, desk lamps, or gizmos within a few feet that might have a switching power supply inside. Next, cover the network analyzer with some aluminum foil to see if the glitches are being delivered via RF. My desktop wi-fi access point does that sometimes. If that also fails, drag your network analyzer and scope to another part of your shop (or cave), that's away from all the gizmos, and see if the problem persists. In other words, determine if the garbage is internally generated, externally radiated, or conducted via the power lines, clip leads, cables, etc.   If you really want to see the noise, glitch, trash, garbage, or whatever signal, set you scope so that the horizontal trigger is off and the horizontal sweep is free running. Then, slooooooowly vary the horizontal sweep until you see fairly stable glitches. If the noise is periodic, you should be able to see something.     -- 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

Cursitor Doom <curd@notformail.com>: Jan 13 12:18AM On Sun, 12 Jan 2020 17:17:04 -0500, Phil Hobbs   >Frequency domain glitch? You mean a discrete spur? >A glitch is a transient time-domain animal.   I could have put it better I guess. What I mean is I'm seeing thin spikes in the RF output spectrum of the VNA at other frequencies than the desired one. I'm guessing these spikes are the result of unwanted transient voltage spikes present on the DC VCO control voltage which sweeps the RF output frequency from 4Mhz through to 1.3Ghz.   >A DSO can save a single >instance, or (with averaging) ignore the noise and asynchronous >background and just reproduce the glitch itself.   Well, Jeff has posted some advice for me on that aspect which I intend to try out tomorrow using my Tek DSO which is probably much better suited to the task than the analogue one I've hithertofore been using.. --   No deal? No problem! :-D

Cursitor Doom <curd@notformail.com>: Jan 13 12:24AM On Sun, 12 Jan 2020 14:22:35 -0800, Jeff Liebermann <jeffl@cruzio.com> wrote:   >gizmos within a few feet that might have a switching power supply >inside. Next, cover the network analyzer with some aluminum foil to >see if the glitches are being delivered via RF.   Yeah, I did try all that and it didn't help, Jeff. Also there's no glitches or noise when I pull the RF signal away, so at least it's not something coming from the spectrum analyser.   >other words, determine if the garbage is internally generated, >externally radiated, or conducted via the power lines, clip leads, >cables, etc.   I *suspect* noise is somehow getting onto the DC VCO ramp voltage and manifesting as spikes in the RF output of the VNA accordingly. Fortunately, there is a jack in the back of the VNA for the application of an external VCO control voltage, so I plan to avail myself of that with a big old linear bench supply and see if the problem goes away.   >and the horizontal sweep is free running. Then, slooooooowly vary the >horizontal sweep until you see fairly stable glitches. If the noise >is periodic, you should be able to see something.   Thanks, Jeff. Duly noted!   --   No deal? No problem! :-D

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Jan 12 07:40PM -0500 On 2020-01-12 19:18, Cursitor Doom wrote:   > I could have put it better I guess. What I mean is I'm seeing thin > spikes in the RF output spectrum of the VNA at other frequencies > than the desired one.   Which is a discrete spur. Gotcha.   > I'm guessing these spikes are the result of unwanted transient > voltage spikes present on the DC VCO control voltage which sweeps the > RF output frequency from 4Mhz through to 1.3Ghz.   If there's a forest of them, spaced at equal intervals, they could be coming from a periodic time-domain source.   > intend to try out tomorrow using my Tek DSO which is probably much > better suited to the task than the analogue one I've hithertofore > been using..   Yeah, I'm fonder of analog scopes than JL is, but my beautiful Tek 2467 hasn't been used in quite awhile, whereas I use the 1180x, TDS 694C and TDS 784As most days that I'm in the lab. For manual driving, the 2467 has the best triggering of the lot, but it's very hard to beat a DSO for general use.   Cheers   Phil Hobbs     -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510   http://electrooptical.net http://hobbs-eo.com

Cursitor Doom <curd@notformail.com>: Jan 13 01:46AM On Mon, 13 Jan 2020 00:24:38 +0000, Cursitor Doom >>horizontal sweep until you see fairly stable glitches. If the noise >>is periodic, you should be able to see something.   >Thanks, Jeff. Duly noted!   Oh, and btw, I know you like details such as this, I'll be using my Tek 2232 DSO for this measurement. I don't really get on with digital scopes, but seems like there's little alternative for this job. :(   --   No deal? No problem! :-D

Cursitor Doom <curd@notformail.com>: Jan 13 01:59AM On Sun, 12 Jan 2020 19:40:23 -0500, Phil Hobbs >> RF output frequency from 4Mhz through to 1.3Ghz.   >If there's a forest of them, spaced at equal intervals, they could be >coming from a periodic time-domain source.   There *are* equally-spaced spikes at the lower end of the spectrum, up to about 100Mhz, but thereafter they assume a far more random appearance - although they are NOT random as they reappear at the same place on the spectrum and at the same amplitude with each sweep. Plus there *is*lower-level truly random noise around 500-600Mhz - so looks like 3 different and unrelated faults to fix!! I do love my vintage test gear, but I often spend more time fixing it than using it! :(   >TDS 784As most days that I'm in the lab. For manual driving, the 2467 >has the best triggering of the lot, but it's very hard to beat a DSO for >general use.   I only have one DSO out of 13 scopes in all: the Tek 2232. It's nothing special; it was okay in its day I guess, but I'm sure John's cheapo Chinese Rigol could piss all over it in a head-to-head "test-off" lol. --   No deal? No problem! :-D

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Jan 12 10:00PM -0500 On 2020-01-12 20:59, Cursitor Doom wrote: > nothing special; it was okay in its day I guess, but I'm sure John's > cheapo Chinese Rigol could piss all over it in a head-to-head > "test-off" lol.   I'm the other way round: 2 analogue scopes out of 9 working ones: a 475A and a 2467. The others are TDS 784As, a TDS 694C, 11802, 11801C, HP 54something, and an Owon something-or-other.   Cheers   Phil Hobbs   -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510   http://electrooptical.net http://hobbs-eo.com

Jeff Liebermann <jeffl@cruzio.com>: Jan 12 07:59PM -0800 On Mon, 13 Jan 2020 01:46:08 +0000, Cursitor Doom   >Oh, and btw, I know you like details such as this, I'll be using my >Tek 2232 DSO for this measurement. I don't really get on with digital >scopes, but seems like there's little alternative for this job. :(   Bad idea. The Tek 2232 has both digital and analog storage: <https://www.tek.com/datasheet/2232-digital-and-analog-oscillscope> I suggest you use it as a conventional analog scope for the untriggered horizontal sweep. If the frequency of the glitch source is stable, you should be able to "tune" it in by adjusting the horizontal sweep (with the trigger turned off). That works much better in analog mode than in digital. Better yet, go back to using your analog Tek 2465A for looking at the VCO control voltage.   Incidentally, I just noticed that you screwed up in your original posting. You provided most of the details, a few of the numbers, but failed to describe the "weird problem with the network analyzer" and what "spurious spikes in the frequency domain on the RF output" might be. Is that like a spurious RF signal appearing on the SA swept display? If so, are you picking up some junk from nearby radio or TV stations? If you can see it, what's the frequency on the SA? I can also imagine that your test setup or cabling may be causing these problems. A probe on the VCO line could easily pickup RF junk from everywhere.   All this goes back to my three commandments for getting a sane answer to questions on Usenet: 1. What problem are you trying to solve? Just one or two lines and leave the details for later. 2. What do you have to work with? What's your level of expertise and what tools and test equipment do you have available? 3. Where are you stuck and what did you do to get there?     -- 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>: Jan 12 08:21PM -0800 On Mon, 13 Jan 2020 00:18:13 +0000, Cursitor Doom >the desired one. I'm guessing these spikes are the result of unwanted >transient voltage spikes present on the DC VCO control voltage which >sweeps the RF output frequency from 4Mhz through to 1.3Ghz.   I would guess(tm) that they are mixer spurs produced by the two oscillators used to produce the network analyzer RF output signal. A clue as to their relative amplitude compared to the RF output would be helpful.   Look at the spurious stuff coming out of the network analyzer. Now, vary the network analyzer frequency and see how they move. You can tell the order (harmonic number) of the spurious components by how much they move. For example, if you change the network analyzer 1 MHz and the spur moves 3 MHz, than you are dealing with the 3rd harmonic of one of the two input signals to the mixer in the network analyzer.   I also suspect that you might be picking up RF from nearby radio and TV broadcast stations. Install a small antenna into the RF IN port of your spectrum analyzer and see if there are signals at the same frequencies that you are seeing them on the network analyzer RF output. If so, you might check the shielding and grounding in the network analyzer.   >to try out tomorrow using my Tek DSO which is probably much better >suited to the task than the analogue one I've hithertofore been >using..   Yep. Failure to observe my advice will result in divine retribution.   -- 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

dplatt@coop.radagast.org (Dave Platt): Jan 12 08:05PM -0800 In article <343m1fdifutpe3ni0c1mv0vg05pb2ev4o2@4ax.com>, >my landline number. The first time, the telephone rang. A little >while later, I tried it again, and by golly, it did not ring. I contacted >Verizon tech support. A service man is scheduled to come Monday.   That's one of the best diagnostic techniques for a lot of phone problems.   I've found that the following sort of phrasing works wonderfully well: "The problem exists at the demarc, with all premises wiring disconnected from the demarc, and can be demonstrated using either of two different telephones plugged directly into the demarc jack."   That tells the telco customer-service rep (and the tech that they eventually send out) two things: the problem is in _their_ equipment (not yours), and you know enough about the situation that they can't scam you into agreeing to pay for a service call for your inside wiring.

Jeff Liebermann <jeffl@cruzio.com>: Jan 12 03:05PM -0800 >occurs above a preset threshold.   > Example: With this DMM hooked up to a circuit, if the voltage rises >above 12VDC (example), the DMM will BEEP.   I don't know of any such device that resembles the common DVM/DMM. However, the industrial control market is full of DPM (digital panel meters) and battery monitors that have alarm outputs. When the display voltage gets out of range, either too high, or too low, it closes a relay. Since your application isn't particularly critical and precision isn't important, something from China or surplus should suffice. Some examples: <https://www.ebay.com/itm/LED-Display-Panel-Digital-Voltmeter-w-Alarm-Indicator-3-Way-DC-0-99-9V-Red/253074549230> <https://www.ebay.com/itm/DA8-RRB-Digital-Sensor-Meter-2-Relay-Alarm-Output-4-digit-LED-Display-D7K0/133289489539> <https://www.ebay.com/itm/Universal-Battery-Alarm-Panel-Meter-4-50VDC-33991-ME/322938101800> <https://www.ebay.com/itm/1-H-P-Edge-Taunt-Band-Panel-Meter-Model-6403-wt-Low-High-Alarm-settings-0-300/312554778647> <https://www.ebay.com/itm/Battery-Monitor-6in1-VOLT-AMP-AH-Time-Power-Protection-Alarm-Buzzer-DC-200V-300A/153388652680> etc...   You might also consider building such a device using a "window comparator" or "window detector" circuit. <https://en.wikipedia.org/wiki/Window_detector> <http://www.learningaboutelectronics.com/Articles/Window-comparator-circuit.php> etc...   -- 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

David Farber <farberbear.unspam@aol.com>: Jan 12 11:32AM -0800 I'm looking to get this Philco 37-630 radio repaired. It turns on but there's no sound. Pictures of it are here. https://app.box.com/s/dae1dyjdv2m0wpfaa0o01zmk1kpwgov3   I am not interested in repairing it myself as I've never repaired any audio equipment made before 1960. This is a favor for a friend and once I pull it out of the cabinet and hand it to him, I'd like to give him the name and address of a reliable shop, preferably near the Central Coast of California as we live in San Luis Obispo County.   Since it isn't feasible to ship the entire piece of furniture and the wiring and speaker have seen better days, is there a specific disassembly procedure I need to follow?   Thanks for your reply. -- David Farber Los Osos CA

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