- Watch this: video Amazon energy saving - 4 Updates
- Scope keeps blowing fuses - 10 Updates
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| Ali J <ali.jaffar07@gmail.com>: Oct 24 01:39AM -0700 On Saturday, July 9, 2022 at 11:00:39 AM UTC-4, Peter W. wrote: > True, "Caveat Emptor" is applicable. At the same time, the Solar Industry, and its Shills owes the average consumer honest and complete answers to specific questions. Certainly no less than that. What is clear, however, from the advertising out there is that those 'honest answers' are thin on the ground. > Peter Wieck > Melrose Park, PA I just came across some good news here about solar's many benefits in Pennsylvania: https://inspiritingly.com/solar-pa/ Beyond reducing your utility bill, the tax credits are amazing, standing at 26% federal, in addition to much more from States and even some local financial incentives. Not only that but it provides American jobs that CAN'T be outsourced. |
| "Peter W." <peterwieck33@gmail.com>: Oct 24 04:11AM -0700 Latest proposal we had from a 'legitimate' solar installer (September) would cost us $32,000 up front, $22,400 after subsidies, and have an 11year, 4 month payback. Not my numbers. The installer offered, what he described as 'very generous' financing at 3.2%. That comes it at $218.37 per month for ten years, or a total of $26,204.40. Extending the payback to just over 13 years. Again, not my numbers, but those provided by the installer. This for a 10KW roof-mounted installation. Not including any related roof repairs. Yes, we have enough roof facing south to accommodate this level of installation. At this moment, we have a locked in contract with a renewable provider for our electric power at $0.0630 KWH for the next three years, with four (4) three-year options at a capped rise of 8% every three years. Our present monthly electric bill (annual average/12) is $140/month. Let's use the rate after the third option $152.28. We will pay our local utility to transport the power in any case one way or the other, but somewhat less for the power we consume on-site - which will not be transported. So, let's look at a blended rate of $0.10/KWH, vs. the $0.14 we are paying now for both generation and transport. And let's use 20% of our present consumption. So, we will still be paying the power company $37/month for small use, and connection fees. So, our average savings will be, in reality, very roughly $120/month. Factor inflation, make that $200/month. $26,204.40/200 = 131 months, several days. So, a better number is about an 11 year payback. Better than 'promised' by a few months. What we have not calculated: a) Any roof repairs - minimal in our case as the roof is only three years old with a 30-year NDL warranty. b) Increase in our homeowner's insurance - per our agent (Farmers), that would come to about $400/year. c) Maintenance & repair (M&R) - life of a single grid-tie inverter is about 10 years, and the cost would be about $3,500 installed. Micro-Inverters (panel mounted) have about a 6-year life and require removal of the panel to repair. Not cheap. Does not include snow and leaf removal. Solar panels are series-mounted cells, so if one cell goes 'dark' the entire string goes dark. d) Eventual removal, disposal, and roof repair at end-of-life. Or, I can have power delivered from the Rocky Ridge wind farm in central PA at a reasonable cost. And have someone else worry about it. And, take that same $218.37 and put it into an annuity at 4.2% - what they are paying these days - and have $37,208 in the bank after that same 11 years. We are pretty efficient for a 4,200 s.f. three-story center-hall colonial built in 1890. We use splits (SEER 25) for heating and cooling, central heat is a 97% efficient boiler, and there are thermostatic valves on the radiators. So, we can keep the house at a reasonable 58 - 60F in the winter, and eight rooms have splits in them which we may set at any temperature we like. And, at no time did we steal from other taxpayers. Peter Wieck Melrose Park, PA |
| "Peter W." <peterwieck33@gmail.com>: Oct 24 09:09AM -0700 Fascinating that you should link to a Canadian website registered just in June of 2022, and updated just today. And, per my protection software, also a phishing site. |
| "Peter W." <peterwieck33@gmail.com>: Oct 24 09:11AM -0700 Not to pile it on or anything: https://ecogenamerica.com/cost-of-solar-panels-in-pa/ |
| Cursitor Doom <cd@notformail.com>: Oct 23 05:58PM +0100 On Sun, 23 Oct 2022 09:36:24 -0700 (PDT), "Peter W." >If the alternative is landfill, then heroic measures are justified. I totally get where you're coming from here. >If the alternative is 'sending it out', unless you wish to did deeper - and all indications are that you do not - then go ahead and send it out. I'm not sure it's worth the expense, because there's another fault with this scope that will most likely still be present even if the present one is fixed. In fact, this 'other fault' may well have caused the current one. This 'other fault' involved the displayed traces suddenly turning extremely bright, accompanied by lines of dots. It materialised only rarely, but I was out of the room when the scope went *phut* so have no idea if there's any link to the current fault or not. I'm beginning to suspect those caps may have failed at some time in the past, because for them to go *bang* with that amount of crap sprayed everywhere must surely have resulted in a great deal of acrid smoke being released - yet there was none discernable. And if those caps fail open circuit (which they both did despite being X2 safety ones which are supposed to fail short) then the scope can contintue to function pretty well as normal so long as the mains supply is reasonably clean. >There is no magic bullet. How true! |
| Jeff Liebermann <jeffl@cruzio.com>: Oct 23 11:16AM -0700 On Sat, 22 Oct 2022 15:26:04 +0100, Cursitor Doom <cd@notformail.com> wrote: >Hi all, Bah Humbug. >So my main analogue scope, a Tek 2465A, has gone faulty. Keeps blowing >main fuses (the 2A one on the rear panel). "Oscilloscope Restoration Project - Repair Tektronix 2465B 400MHz" <https://cdn.hackaday.io/files/1638907011869760/Tektronix-2465A-B-Oscilloscope-Restoration-Repair.pdf> "Symptoms: This is my lab unit, which suddenly started blowing its main AC fuse." "Amazing Tektronix 2465 Repair Information" <https://jestineyong.com/amazing-tektronix-2465-repair-information/> Concerning my Tektronix 2465 repair I yesterday replaced both 0.068uF 250VAC caps after I had received the ordered new 275VAC caps. Both caps are C1016 and C1018 in the Tektronix service manual schematic on Board A2A1. And only the C1016 0.068uF capacitor had blown which also damaged the serie resistor R1016 of 68 ohm 5% which also was replaced. They protect the Diode Bridge CR1011 (600V 3A Fast Recovery type RKBPC606-12) against damage by high AC power voltages. The Diode Bridge was not damaged. My oscilloscope is happily working as new again. (48019 HRS of service in 32 years or so). Good luck. -- Jeff Liebermann jeffl@cruzio.com PO Box 272 http://www.LearnByDestroying.com Ben Lomond CA 95005-0272 Skype: JeffLiebermann AE6KS 831-336-2558 |
| whit3rd <whit3rd@gmail.com>: Oct 23 02:13PM -0700 On Saturday, October 22, 2022 at 7:26:11 AM UTC-7, Cursitor Doom wrote: > still blowing fuses. I can't be 100% certain, but I'm pretty sure > there's a fault with the PSU board as I get the briefest whiff of > burning from that area each time I put a new fuse in and power up. First thing to check is the rectifier; that diode bridge can fail, and apply AC to the filter capacitors, and... that'll take out the fuse. Not sure why the RIFA capa goes, though; maybe just a power surge some time last week? There seem to be some surge-suppressors (gas discharge?) in the diagram, they might have failed short in a surge.. |
| Cursitor Doom <cd@notformail.com>: Oct 23 10:56PM +0100 On Sun, 23 Oct 2022 14:13:30 -0700 (PDT), whit3rd <whit3rd@gmail.com> wrote: >time last week? >There seem to be some surge-suppressors (gas discharge?) in the diagram, they might >have failed short in a surge.. Yes, they're each showing about 70k ohms, so can't be responsible. One thing I forgot to mention in my first post was that a wire had come adrift from the cooling fan's supply (poor factory soldering clearly) so this unit had been running for an unknown length of time with no fan. Not sure if that's relevant to the fault here, but it certainly *could* be.... |
| Cursitor Doom <cd@notformail.com>: Oct 23 10:57PM +0100 On Sun, 23 Oct 2022 11:16:19 -0700, Jeff Liebermann <jeffl@cruzio.com> wrote: >"Amazing Tektronix 2465 Repair Information" ><https://jestineyong.com/amazing-tektronix-2465-repair-information/> >Good luck Thanks for the links, Jeff; I'll check 'em out... |
| Phil Allison <pallison49@gmail.com>: Oct 23 04:41PM -0700 st...@swingnn.com wrote: ---------------------------------------------- Phil Allison > I was pointing out a common misunderstanding with multiple capacitors. > Rifa are alone, in parallel or in series and can all fail at the same > time as can smoothing capacitors in parallel. ** Shame how you own example contradict that idea. ......Phil |
| Phil Allison <pallison49@gmail.com>: Oct 23 04:46PM -0700 Cursitor Doom wrote: --------------------------------- > And if those > caps fail open circuit (which they both did despite being X2 safety > ones which are supposed to fail short) ** Really ? Where did you get that idea? Plenty are found open or with low values after long times in service. X2 dropping caps used in smoke alarms regularly fail open. But those Rifa ones love to smoke and burn. .......Phil |
| Jeff Liebermann <jeffl@cruzio.com>: Oct 23 05:13PM -0700 On Sun, 23 Oct 2022 16:46:49 -0700 (PDT), Phil Allison >X2 dropping caps used in smoke alarms regularly fail open. >But those Rifa ones love to smoke and burn. >.......Phil RIFA caps smoke, especially the old ones. This is typical for vintage Tektronix scopes and RIFA caps: "Old RIFA capacitors and a disaster story" <https://www.eevblog.com/forum/chat/old-rifa-capacitors-and-a-disaster-story/> YouTube videos featuring smoking RIFA caps: <https://www.youtube.com/results?search_query=rifa+capacitor> I sometimes test the HV leakage in capacitors using an ancient Megger: <http://www.learnbydestroying.com/jeffl/pics/Megger/Megger-Major.jpg> <https://www.vintage-radio.net/forum/showthread.php?t=73265> Unsolder the capacitor for testing. You really don't want a high voltage power source connected to your oscilloscope. -- Jeff Liebermann jeffl@cruzio.com PO Box 272 http://www.LearnByDestroying.com Ben Lomond CA 95005-0272 Skype: JeffLiebermann AE6KS 831-336-2558 |
| legg <legg@nospam.magma.ca>: Oct 24 09:29AM -0400 On Sat, 22 Oct 2022 15:26:04 +0100, Cursitor Doom <cd@notformail.com> wrote: >Thanks, >CD. >https://disk.yandex.com/i/UhxATIy-6Y0LIA Don't know your line voltage, but if it's 240, check the input voltage setting on the scope. If RFI caps are replaced and bridge is ok, check big electros (C1021, C1022) and main switch (Q1050) for shorts. At 240V, a leaky bulk cap can blow the gas tubes. Once a gas tube fires, it's breakover voltage will reduce, so must be replaced, too. RL |
| legg <legg@nospam.magma.ca>: Oct 24 09:46AM -0400 On Sun, 23 Oct 2022 17:13:54 -0700, Jeff Liebermann <jeffl@cruzio.com> wrote: ><https://www.vintage-radio.net/forum/showthread.php?t=73265> >Unsolder the capacitor for testing. You really don't want a high >voltage power source connected to your oscilloscope. The smoking caps were metalized paper construction. These were good enough in their day, with a demonstrated mtbf and safe self-healing, while seals lasted. The outer sealing body tended to shrink and crack with age, allowing ingress of air and moisture, compromising performance. They are no longer made. Metalized film parts are usually less dramatic in self-clearing of internal faults, but in extreme cases, you still get thermal runaway, as the faulting area expands and eats away at succesive layers of the wrapped structure. Film parts will generally fail at the end schoopage joint, where metalization and film stresses accumulate in mfring. RL |
| ehsjr <ehsjr@verizon.net>: Oct 23 01:20PM -0400 On 10/22/2022 11:57 PM, John Crane wrote: > It's a 12-181b. > As luck would have it, it came with a little paper schematic and user's > guide tucked in the battery compartment....attaching a jpg of it. Below is a relatively long post concerning a lower probability cause of the problem than the cube itself. It was mentioned earlier, but dismissed when it should not have been. I'm posting this because there is a small possibility that there is a safety issue in your home. You have NOT eliminated all possibilities of EMI/RFI Walk it down the road, as was mentioned. That is, take it somewhere to a place far away from any power lines, houses, buildings etc where electrical devices are. If it still buzzes then you know the problem is within the cube. Sources of EMI/RFI can be in a nearby neighbor's house, a power line fault such as a cracked insulator or even a loose connection in the wiring in your house. It doesn't have to be a new electrical device in your house, even though that is a most likely cause in many cases. If the cube works properly when walked down the road, but starts buzzing as you near your house, use it as a detector to try to locate the source - perhaps a power line or a neighbor's house. If the source is something in your house, you can shut off breakers until you determine which circuit "hosts" the noise making device, then further isolate by restoring power to the circuit and unplugging/switching off one device at a time. Don't overlook devices that you cannot switch off like doorbell or thermostat transformers hard wired devices and so forth. If the problem is not found in any device you can unplug or switch off, it could be a loose connection in the wiring. That is serious, as a fire could result. I hope diagnosis/fix turns out to be simple and does not involve safety at all. Good hunting! Ed |
| Jeff Liebermann <jeffl@cruzio.com>: Oct 23 10:45AM -0700 On Sat, 22 Oct 2022 22:57:45 -0500, John Crane >It's a 12-181b. >As luck would have it, it came with a little paper schematic and user's >guide tucked in the battery compartment....attaching a jpg of it. Thanks. The schematic is somewhat out of focus but I was able to make it more readable using the "Sharpen" feature in Irfanview. I know both IC's quite well, having used them in various marine radio designs around 1975. The MC3357 has a large amount of gain and is therefore likes to oscillate with minimal provocation. In order from most probable: Electrolytics: C28, C15. 0.01uF ceramics: C22, C30, C10. My best guess(tm) is C15. Also, check the DC voltage across D4. It should be 5.1VDC I suggest you bypass the capacitors with a replacement capacitor, one at a time, instead of removing and replacing. It's quicker and easier. If you need to remove the wax, a hair dryer or heat gun will work. MC3357 datasheet: <https://www.digchip.com/datasheets/download_datasheet.php?id=643405&part-number=MC3357> I can think of some less likely failures and parts if cap replacements show no improvement. As I previously suggested, probe the PCB with your finger and look for an area that produces a change in the buzzing noise. Whatever failed is nearby. -- Jeff Liebermann jeffl@cruzio.com PO Box 272 http://www.LearnByDestroying.com Ben Lomond CA 95005-0272 Skype: JeffLiebermann AE6KS 831-336-2558 |
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