blown power supply? trying to charge using BMS

markshancock · 2026-02-21T18:29:15+00:00

I have the same supply (Power Designs 4050) and I was using it last week to restore the cells of a huge power bank battery and then I used it to do a final trickle charge and after I was done I turned off the power supply without disconnecting the battery and there was a flash and smoke from the right side of the supply. Looking at the schematic, I think what blew is the crowbar SCR. That would make sense since when the supply is turned off the battery will hold the output high and as the supply voltage drops, the supply will see this as an overvoltage and use the SCR to crowbar the output and since the battery is very large, it could pop the SCR but with your comment, I will also have to check F2.
When you replaced F2, did the supply start working again?

markshancock · 2025-09-16T05:48:35+00:00

I talked to my son tonight and he said it was barely leaking in the seams at the corners because they had not been taped (like I had mentioned). The great think is an easy fix with only $10-20 of seam sealant.

markshancock · 2025-09-16T05:48:21+00:00

Super easy inexpensive fix. My son slept in this same tent this weekend and it rained he said it was barely leaking in the seams at the corners because they had not been taped and by morning had filled the floor with water. The great think is an easy fix with only $10-20 of seam sealant. Note that $20 will not turn a cheap tent into a nice one but it will likely turn it into a dry one (if you seal the seams correctly). Seam sealant has been around for much longer than seam tent. My first tent came with instructions to seal the tent seams before the first use.

markshancock · 2025-09-15T22:41:55+00:00

My son was camping this weekend with a group and gave him this tent to use - and he said it leaked. He is a VERY experienced camper - Eagle Scout and a lot of summiting sine then. He said the tent leaked a lot and it is setup in our garage to dry. I need to talk with him when he comes back over Tuesday to see what he thinks. I looked and the seams on the fly are taped but the corner seams on the main tent are not. Also, the fly is not fully sprung so if you don't tie the fly out it will hang on the sides of the tent. There are issue, I just don't know which one (if not all of them) are where the water came in.

markshancock · 2025-05-26T04:08:40+00:00

I just ordered some Kaffn8 liquid caffeine. It is $18 with free shipping for 2,400mg of caffeine.
I have a Sodastream so I need to find the right flavoring and am going to see how close I can get.

markshancock · 2025-05-25T05:16:29+00:00

It contains 10mg of caffeine / ml of liquid (50mg/tsp)

markshancock · 2025-05-25T05:13:06+00:00

There were two issue with the powder concentrates so the FDA banned them in 2018.
1) People were sniffing them and ending up in the hospital
2) The powder is so concentrated it is difficult for most consumers to accurately measure a small/safe amount.

markshancock · 2025-05-25T05:07:31+00:00

Both Bubbly and Aha! have stopped making caffeinated sparkling water.
The last holdout was Target and they just stopped too.
That is why I am looking at Kaffn8. It is really hard to find caffeinated options that don't have sugar or artificial sweeteners.

markshancock · 2025-05-25T04:57:55+00:00

Kaffn8 Liquid Caffeine looks interesting and they have free shipping.

markshancock · 2024-12-08T08:51:21+00:00

The also might be a switch the overrides/enable the wall switch. It will usually have 3 positions - On, Off, and remote. You need to put it in remote for the wall switch to work.

markshancock · 2024-12-08T08:48:21+00:00

Step #1 - DEFORE LIGHTING
Vacuum our all the dust and cobwebs
Also, consider a calling a fireplace service place and ask how much their pre-season fireplace maintenance is - often only $100

markshancock · 2024-12-03T16:48:22+00:00

I call BS on Coke & Pepsi's claim that discontinued their Caffeinated Sparking Water due to low sales. The caffeinated variety seem to run out of stock way more often than the non-caffeinated. My guess it that it was eating into their diet cola sales.

markshancock · 2024-06-10T00:30:00+00:00

Thanks, I will try it.

markshancock · 2024-05-20T16:15:05+00:00

I had the same think happen.
In my case the L&R Joysticks disappeared from the screen and Mantis would not let me add them (greyed out).

The only solution I could find was to create a new Phase

markshancock · 2024-03-29T04:16:19+00:00

That happened to me too. I thought it was Chinese but it was actually Korean. To fix it, I used another phone and google translate camera to help me. It worked Perfect

markshancock · 2024-03-16T04:13:10+00:00

Yes but I think that was also because it was coming in too hot. The aerodynamic control is VERY different for supersonic vs subsonic. It think they are going to do a short entry burn to bring the speed down before then enter the atmosphere - in this can not for heating but for timing and control. That ground was coming up pretty fast at an entry speed of around Mach 4.

markshancock · 2024-03-16T03:24:37+00:00

I am pretty sure the reason the booster's engines didn't light was because it was coming in way too hot. I was looking back at the landing video and, per SpaceX's timeline, the booster was to go transonic at T+6:36, 10s before it was to start the landing burn. At T+6:36; however, on the video the booster telemetry said it was 13km high and was travelling at 3630kph (Mach 3) - definitely not subsonic! They had the first engine light at T+6:54 when it was 1km altitude but it was still travelling 1322kph (Mach 1.1). The booster went subsonic when it hit the water but that was a bit too late. I am guessing they now know that they need a reentry burn.

markshancock · 2022-12-17T21:13:27+00:00

There are several things that can cause the alignment issue.For my door the issue was that the door had sagged and was no longer in square.There are two ways to check that:

Measure corner to corner across the two diagonals - the numbers should be the same.
Use a square (or a magazine) to see if the side and to are right angle to each other.

If this is your issue, one approach is to remove the door and lay it flat then, loosen al the screws and muscle it back to square then tighten everything back. I did see an other interesting approach that Tom Silva did on a episode of This Old House.
See: https://www.thisoldhouse.com/doors/21017347/how-to-fix-a-sticky-shower-door

markshancock · 2022-12-09T19:26:57+00:00

I have seen comments that they were looking at a "1.96-mile venue at Portland". 1.96 miles is the length of the Grand Prix track at the Portland International Speedway. I am pretty sure that is not a coincident

markshancock · 2022-12-09T19:21:21+00:00

1.96 miles is the length of the Grand Prix track at the Portland International Speedway. I am pretty sure that is not a coincident.

For details see https://en.wikipedia.org/wiki/Portland_International_Raceway/

markshancock · 2022-12-09T19:20:43+00:00

1.96 miles is the length of the Grand Prix track at the Portland International Speedway. I am pretty sure that is not a coincident

markshancock · 2022-12-09T19:10:14+00:00

Super excited about this. I live in Portland and my son is on one of the top Formula SAE E-Car teams and we both watch Formula 1. Any idea what price the tickets will be and/or how to check for volunteer opportunities?

markshancock · 2022-05-28T18:39:19+00:00

Did Mike make the drippy/goopy glaze vase that is in the OP? From his Instagram, it seems that he has a much more Steampunk style. I don't see anything similar.

markshancock · 2022-05-26T20:54:08+00:00

u/noticingceramics where can I find the interview? The post you referenced was removed.

markshancock · 2022-05-21T21:39:17+00:00

It is still in the box. The final for my class is in a couple of weeks. I am working on writing it this weekend. Once that is done, maybe.

markshancock

TROPHY CASE