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amdx <amdx@knology.net>: Jan 11 07:44AM -0600 On 12/23/2020 8:38 PM, Daniel Fynn wrote: > I have built a 555 timer monostable circuit that works fine(when pin 2, the trigger is momentary grounded the output, pin 3 goes high for about 10 seconds before going low again) but now, i need a circuit that will work the same way even when pin 2 (trigger) is held low for say 5 minutes. Meaning when pin 2 is held low for a long time, the output will go high for the same 10 seconds and then will go off. it should stay off until pin 2 is removed from ground and sent back to ground again before the output can go high again. > The circuit is for a project that has an infrared obstacle sensor as its input and operates a light when it detects a hand. What I want is even if the hand stays there for a longer time the light should go off after 10 seconds until the person removes the hand and brings it back before the light will come on.    How about a differentiator?   If the sensor input is changed slowly, (slow fall time) that might not work and you would need a schmitt trigger before the differentiator.   > http://evalidate.in/lab1/pages/RC/RCDifferentiator/RCDifferentiator_I.html This shows a square wave, But your transition from B+ to 0V will give a negative pulse to trigger Pin 2.                         Mike     -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

Cydrome Leader <presence@MUNGEpanix.com>: Jan 11 08:39AM >> let the motor get AC.   > So, the rectifier no longer turned AC output of the controller to DC? > So, the controller wasn't used after that?   Correct. The chopped up AC was no longer full wave rectified into choppy DC. I never looked at the waveforms, but they were probably awful.   >> It worked fine after that. I'm not sure why they added a bridge recitfier >> in the first place, or why removing it made a difference but it did.   > Didn't they need DC to the controller's resistor circuit?   There was no feedback from the rectified output. I keep thinking it was a wall mounted light dimmer or something cheap like that inside the box, but with an electronics-looking knob. >> together looking so I can't even tell if they added the rectifier or the >> OEM did.   > Oh, the rectifier was added after the original sale.   It was added at the factory. My only modification was to remove it, as the support people suggested. >> I'm sort of tempted to try the drill press with a properly designed >> industrial speed controller (Dart Controls), with and without the bridge >> rectifier to see how it behaves.   I haven't run this test yet, but will soon.

Cursitor Doom <cd@noreply.com>: Jan 10 04:45PM On Sun, 10 Jan 2021 16:34:13 +0000 (UTC), Bertrand Sindri >>>> before developing dementia, so I think it's fair to assume there's >>>> an internal power supply of some sort.   >Why is this "safe to assume"?   Fair point. Assumptions are the mother of all fuckups - as I've said here many times myself! >stored in a tiny amount of flash on the main chipset to provide the >bootstrap necessary to find the rest of the settings on some cloud >server.   You see this is all like rocket science to me. Never in a million years would that have occurred to me. If my favourites are stored in the cloud rather than locally then that's a major breach of trust Roberts has committed. And confidentiality!   >wage phone worker having a table of "customer quoted symptoms" vs. >"quoted repair cost" and the minimum wage worker just reading you off >the quote for the item that sounded most close to your description?   Look, I'm an old dude. I have no idea what goes on in these places nowadays. I can only go by my increasingly outdated experience which is set firmly in the past (25+ years minimum).   >> are showing as anything between 1000uF and 1200uF on my Peak ESR70 >> meter. I've never known caps so far out of tolerance before.   >In circuit or out of circuit measurement?   In circuit. And they're not in parallel.

Cursitor Doom <cd@noreply.com>: Jan 10 04:46PM On Sun, 10 Jan 2021 15:43:08 +0000, Andy Burns <usenet@andyburns.uk> wrote:     >> Yes, it remembers the password and accesses the router no problem.   >So it has *some* functioning non-volatile storage then, wonder if it >constantly writes your favourites to flash and has worn it out?   I wouldn't have thought so, Andy. It would take infintintely more write-cycles than I have time to enter data. My settings and favourites have remained largely unchanged for many years.

Bertrand Sindri <bertrand.sindri@yahoo.com>: Jan 10 04:55PM >>three quarters you have not yet disassembled?   > Yeah, I know, I know. I'm not a technician so I don't think like a > technician; sorry about that.   That is just a copout.   Realizing that you've not seen 100% of the boards in the housing is not "thinking like a technician". One does not have to "think like a technician" to realize that if you have not found what you are searching for, but have only searched one quarter of the total, that just maybe the item you seek is in the remaining three quarters.   Although your other posts have opened the very good possibility that the device has zero local storage beyond WiFi credentials.

Bertrand Sindri <bertrand.sindri@yahoo.com>: Jan 10 05:06PM >>some cloud server.   > You see this is all like rocket science to me. Never in a million > years would that have occurred to me.   This just requires thinking like a "cost-cutting businessman".   Question: How can we reduce the manufacture cost of this product?   Answer: Eliminate some of the components.   Question: How can we do that?   Answer: Since it already has internet access to operate, we could eliminate the local storage of settings, allowing us to eliminate a flash chip of X amount, or a battery backup of X amount.   > If my favourites are stored in the cloud rather than locally then > that's a major breach of trust Roberts has committed. And > confidentiality!   Indeed, but none of the above means they /did not/ commit this breach for the purpose of cost cutting.   >>the quote for the item that sounded most close to your description?   > Look, I'm an old dude. I have no idea what goes on in these places > nowadays.   Again, think like a "cost cutting businessman". How do I reduce the cost of my "support team"? Answer: Hire the cheapest workers possible and give them a canned script to read from and follow (canned script is so I don't have to pay them for 'smartness'). The very concept of telephone support people having a "script" that they strictly follow has been the subject of jokes and parodies for a good 30+ years.   >>> ESR70 meter. I've never known caps so far out of tolerance before.   >>In circuit or out of circuit measurement?   > In circuit. And they're not in parallel.   And you know this because you have the schematic or have reverse engineered the schematic from the PCB?   If you have no schematic, you are again 'assuming' they are not in parallel.

Bertrand Sindri <bertrand.sindri@yahoo.com>: Jan 10 05:13PM > I wouldn't have thought so, Andy. It would take infintintely more > write-cycles than I have time to enter data. My settings and > favourites have remained largely unchanged for many years.   This is another unsafe assumption. It is possible that the power-down sequence could be:   detect press of soft-power button   write user settings from RAM to flash   power down   Where "write user settings" occurs whether or not you have made any changes to those settings.   And maybe the price quote you got from their phone support was really the cost for: "replace the worn out flash chip".

Andy Burns <usenet@andyburns.uk>: Jan 10 05:35PM Bertrand Sindri wrote:   > maybe the price quote you got from their phone support was really > the cost for: "replace the worn out flash chip".   You can nuke its settings   press menu, main menu, system settings, factory reset, yes   also you may have linked the device to an online account via   <http://www.wifiradio-frontier.com>   Might your account have been locked-out?

Cursitor Doom <cd@noreply.com>: Jan 10 06:32PM On Sun, 10 Jan 2021 17:35:35 +0000, Andy Burns <usenet@andyburns.uk> wrote:     >also you may have linked the device to an online account via   ><http://www.wifiradio-frontier.com>   >Might your account have been locked-out?   I don't have any such account! Certainly nothing that *I* have created anyway. Unless this is something Roberts do without telling you.

Cursitor Doom <cd@noreply.com>: Jan 10 06:45PM On Sun, 10 Jan 2021 17:06:03 +0000 (UTC), Bertrand Sindri   > Answer: Since it already has internet access to operate, we could > eliminate the local storage of settings, allowing us to eliminate a > flash chip of X amount, or a battery backup of X amount.   ... At the cost of setting up some sort of user account on the internet for the customer, which also requires time and money to implement. I don't see the saving - if any - is worth the extra bother.   >so I don't have to pay them for 'smartness'). The very concept of >telephone support people having a "script" that they strictly follow >has been the subject of jokes and parodies for a good 30+ years.   Firstly, I don't believe it's feasible to 'project' (as it's called) one's own thoughts and emotions over others. You can't get inside other people's minds in this way whatever the subject matter may be. And this wasn't some "support team" lacky but rather email replies from someone who clearly understood the issue even though they were only prepared to offer a solution which would benefit the company to the tune of 40 quid.   >engineered the schematic from the PCB?   >If you have no schematic, you are again 'assuming' they are not in >parallel.   But YOU are also *assuming* that *I* am assuming that. The fact that I am doesn't change the fact that you're still making an assumption here. It just happens to be correct on this occasion.

Bernie <bernie.usenet@gmail.com>: Jan 10 07:05PM On Sun, 10 Jan 2021 15:34:07 +0000 > know already what the problem was since they quoted me 40 quid to fix > it I'm just wondering if they don't do anything to the radio but just > renew my subscription or something like that.   https://forums.digitalspy.com/discussion/2337021/roberts-internet-radio-no-access-to-favourites

Bertrand Sindri <bertrand.sindri@yahoo.com>: Jan 10 08:36PM > I don't have any such account! Certainly nothing that *I* have > created anyway. Unless this is something Roberts do without telling > you.   No one is saying *you* created anything.   All that is needed for the radio to save all your user settings in "the cloud" [1] is for each radio to have a unique serial number, and for the maker to run a very cheap server on the 'net to receive a request from the radio and to either return (for a read request) or save (for a write request) the user settings in association with that serial number.   Given that it has a WiFi chipset, it already has a unique serial number, that being the MAC address of the WiFi chip on the board.   So it is very possible for the radio to use a cloud server to store your settings. Whether it in fact does so is yet undetermined. But everything necessary on the radio hardware side to do so is already present. A WiFi chipset (for internet access), a unique serial (the WiFi chipset MAC address), and a CPU (given a WiFi chipset, it likely also contains an embedded CPU as well).       [1] yes, this is not secure, because if you learn someone's radio's MAC address, you could read/write their settings.

Adrian Caspersz <email@here.invalid>: Jan 10 09:55PM On 10/01/2021 20:36, Bertrand Sindri wrote: > also contains an embedded CPU as well).   > [1] yes, this is not secure, because if you learn someone's radio's MAC > address, you could read/write their settings.   Ok, I had a look at the manual. Like my earlier model, it's a ridiculously complicated book more suited to a computer product than an entertainment gadget.   http://www.aeldownloads.com/robertsradio/userguides/STREAM105%20ISSUE.1.pdf   There is also a troubleshooting guide   http://www.aeldownloads.com/robertsradio/TSguides/STREAM%20105%20TS.ISSUE.1.pdf.     In the UK, Roberts was a British brand of radio manaufacturer that catered mostly to the middle class purchaser, and I can hardly see some of those that have remaining memories of old, having some ability left to waddle through that nonsense.   However, I had a waddle. Page 64 of the wordy user manual.   "You should not attempt to update your radio unless it is recommended to you by Roberts Customer Services. Updating the software may remove all network settings, radio station presets and alarm settings from your radio"   So, station presets _are_ stored in flash memory on the device. Have they been lost in a recent software update?   Suggest, (if it still works) registering an account (Page 30) and storing favourites there.   Mr Doom. You won't find a battery or a cap. Give up.   -- Adrian C

Cursitor Doom <cd@noreply.com>: Jan 10 10:59PM On Sun, 10 Jan 2021 21:55:28 +0000, Adrian Caspersz >> the radio and to either return (for a read request) or save (for a >> write request) the user settings in association with that serial >> number.   I see. Well, I never wanted *anything* to do with 'the cloud' - ever. So if that had been the case I'd have had strong words with Roberts!       >Suggest, (if it still works) registering an account (Page 30) and >storing favourites there.   >Mr Doom. You won't find a battery or a cap. Give up.   Many thanks indeed for that summary, Adrian; much appreciated. I have never - knowingly - ever done any updates at all since I bought the thing. I bought Roberts because I've had their broadcast recievers in the past and been very happy with them in all respects. They were a bit pricey (though not as much as a Hacker) but the build and sound quality was very good. Their internet radios, OTOH, have none of that reassuringly solid feel about them. I think I'll reassemble it and have a think about how to proceed from there tomorrow....

Bertrand Sindri <bertrand.sindri@yahoo.com>: Jan 10 11:26PM > pricey (though not as much as a Hacker) but the build and sound > quality was very good. Their internet radios, OTOH, have none of > that reassuringly solid feel about them.   It could be possible that "Roberts" (the brand name) has gone the way of a lot of the traditional US "brand names" of yesteryear (Honeywell, Westinghouse, etc.).   They (the US brands, I have no idea re. Roberts) are nothing more than "Names" owned by some rent-seeking corporation who will sell the right to brand anything as "Honeywell" or "Westinghouse" for the right price.   What you mention re. the massive reduction in build quality is exactly what happened to the products that were "branded" as "Honeywell" or "Westinghouse" (or others) once they became a "brand name for hire". The product build quality plummeted.

Cursitor Doom <cd@noreply.com>: Jan 11 12:35AM On Sun, 10 Jan 2021 23:26:37 +0000 (UTC), Bertrand Sindri >what happened to the products that were "branded" as "Honeywell" or >"Westinghouse" (or others) once they became a "brand name for hire". >The product build quality plummeted.   Exactly. They sold out to get rich (or should I say *even* richer).

Michael Terrell <terrell.michael.a@gmail.com>: Jan 10 01:01PM -0800 On Saturday, December 12, 2020 at 12:24:00 PM UTC-5, John Larkin wrote:     > prized/priced because some people can hear the difference.   > If I paid $25 for a 0.022 uF cap, I bet I could hear the difference.   > I wonder how many of these sorts of things are Chinese fakes.   Black Beauties were oil filled paper capacitors. They were supposed to outlast regular paper caps. Many went bad on the shelf.

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