Badcaps.net Forum
Go Back   Badcaps Forums > Search Forums
Register FAQ Calendar Search Today's Posts Mark Forums Read

Showing results 1 to 25 of 500
Search took 0.02 seconds.
Search: Posts Made By: PeteS in CA
Forum: General Capacitor Questions & Issues 05-16-2022, 12:41 PM
Replies: 356
Views: 473,089
Posted By PeteS in CA
Re: List of Bad Cap Manufacturers

Yep, those caps are preggers and not going to deliver anything good. FWIW, the date on the PWA is February 2012.
Forum: General Capacitor Questions & Issues 05-16-2022, 12:37 PM
Replies: 9
Views: 315
Posted By PeteS in CA
Re: ESR 0.6Ω capacitance -15% absolute must change?

As best I can tell, the PIC16F819 is a general purpose microcontroller, https://ww1.microchip.com/downloads/en/DeviceDoc/39598F.pdf . Perhaps it is being used as a supervisor.

Your 5VSB is...
Forum: General Electronics Technical Discussion 05-13-2022, 12:28 PM
Replies: 39
Views: 1,149
Posted By PeteS in CA
Re: TIP120 Question

Back in the late 70s and into the 80s, transistors were used rather than Darlingtons. At Boschert, we used 2N654# and MJE1300# transistors (TO-204 and TO-220, respectively) from Motorola. That was...
Forum: General Electronics Technical Discussion 05-13-2022, 12:06 PM
Replies: 39
Views: 1,149
Posted By PeteS in CA
Re: TIP120 Question

In addition to limiting the realistic maximum switch frequency, during those turn-on and turn-off times, the device is in its linear reason, i.e. dissipating power. As those turn-on and turn-off...
Forum: General Electronics Technical Discussion 05-12-2022, 11:44 AM
Replies: 39
Views: 1,149
Posted By PeteS in CA
Re: TIP120 Question

redwire is correct that I was confusing a C-B resistor with a Baker Clamp, which uses a diode to reduce storage time. Lo siento.

Basically, transistors' rise, fall, and storage time combine to...
Forum: Troubleshooting Power Supplies and Power Supply Design 05-08-2022, 06:16 PM
Replies: 12
Views: 358
Posted By PeteS in CA
Re: Power Man ip-p300bn7-2 blown

Putting together anecdotal comments I’ve seen around here, I wonder if a lot of the snap-in type caps, which were originally designed for 50/60 Hz usage, are not suitable for the high frequency...
Forum: General Electronics Technical Discussion 05-06-2022, 11:40 AM
Replies: 39
Views: 1,149
Posted By PeteS in CA
Re: TIP120 Question

I sit partially corrected about the TIP120 incorporating B-E resistors. However I think those are to prevent leakage or noise from turning on the Darlington. IIRC, it's a C-B resistor that keeps a...
Forum: General Capacitor Questions & Issues 05-06-2022, 11:28 AM
Replies: 9
Views: 315
Posted By PeteS in CA
Re: ESR 0.6Ω capacitance -15% absolute must change?

I should have done this earlier ... here's a pic of one of the 3 modules in a PWS-0050:
...
Forum: General Capacitor Questions & Issues 05-05-2022, 06:20 PM
Replies: 9
Views: 315
Posted By PeteS in CA
Re: ESR 0.6Ω capacitance -15% absolute must change?

So the PFC appears to be working. That plus the 5VSB means your auxiliary regulator is working.

Do you have that 383V at the inverter MOSFET Drain? If not, you may have an open fuse between the...
Forum: General Capacitor Questions & Issues 05-04-2022, 04:40 PM
Replies: 9
Views: 315
Posted By PeteS in CA
Re: ESR 0.6Ω capacitance -15% absolute must change?

That model is end-of-life.

The capacitance is in spec, for +/-20% tolerance. I'm not sure the ESR you measured is abnormal for a 100uF, 400V electrolytic capacitor. It's hard to compare to catalog...
Forum: General Capacitor Questions & Issues 05-04-2022, 04:22 PM
Replies: 18
Views: 372
Posted By PeteS in CA
Re: What damage can occur when a filter cap explodes?

Actually, I do remember a lytic launch. I was working at Boschert, and a new engineering tech was working on a 48V input DC-DC converter prototype. The assembler had accidentally installed a 7.5V cap...
Forum: General Capacitor Questions & Issues 05-02-2022, 11:17 AM
Replies: 18
Views: 372
Posted By PeteS in CA
Re: What damage can occur when a filter cap explodes?

I haven't heard any lytics going off that dramatically, but my experience is, obviously, finite. OTOH, when a wet slug tantalum went of a couple of feet from me my ears were ringing for an hour or...
Forum: General Capacitor Questions & Issues 05-02-2022, 11:13 AM
Replies: 18
Views: 372
Posted By PeteS in CA
Forum: General Electronics Technical Discussion 05-01-2022, 06:00 PM
Replies: 12
Views: 345
Posted By PeteS in CA
Re: FCL30A015 diode reverse biased shows 35 Ohm, 0.05V forward. Is it gone?

Itís more likely to be made by Compuware, Delta, or Samsung.
Forum: General Capacitor Questions & Issues 05-01-2022, 05:48 PM
Replies: 18
Views: 372
Posted By PeteS in CA
Re: What damage can occur when a filter cap explodes?

If it’s an electrolytic, the liquid electrolyte is very conductive and could cause shorts.
Forum: General Electronics Technical Discussion 04-29-2022, 10:58 AM
Replies: 12
Views: 345
Posted By PeteS in CA
Re: FCL30A015 diode reverse biased shows 35 Ohm, 0.05V forward. Is it gone?

That's a 30A, 15V Schottky. It has a very low forward drop, possibly for use as a high current or'ing rectifier. Its normal characteristics could "fool" a DMM diode checker. I'd suggest doing an...
Forum: General Electronics Technical Discussion 04-29-2022, 10:42 AM
Replies: 6
Views: 256
Posted By PeteS in CA
Re: Resistor value - color coding

Based on the chart below, I'm guessing .3 ohm, 250 ppm tempco.

https://www.neodensmt.com/Content/upload/2019233559/201906241320349978362.jpg
Forum: General Electronics Technical Discussion 04-27-2022, 10:56 AM
Replies: 39
Views: 1,149
Posted By PeteS in CA
Re: TIP120 Question

I suggest adding a resistor base-emitter to reduce sensitivity to leakage and noise. This is normal practice with regular transistors, and I would think the high beta of a Darlington would make doing...
Forum: Troubleshooting Power Supplies and Power Supply Design 04-25-2022, 11:34 AM
Replies: 3,195
Views: 1,040,344
Posted By PeteS in CA
Re: Power supply build quality pictorial. part 2

400W? No. The heatsinks might be good for 300W, but that main transformer and 470uF input caps put the practical continuous power in the 250W range, IMO.
Forum: Troubleshooting Power Supplies and Power Supply Design 04-22-2022, 11:50 AM
Replies: 3,195
Views: 1,040,344
Posted By PeteS in CA
Re: Power supply build quality pictorial. part 2

How often have I posted this: those heatsinks do look reasonably substantial. The main transformer looks reasonable as well. 820uF for the input lytics seems a bit marginal for 500W (more OK for...
Forum: Troubleshooting Power Supplies and Power Supply Design 04-14-2022, 03:37 PM
Replies: 70
Views: 1,960
Posted By PeteS in CA
Re: A question about PWM IC's

Start-up current comes from "VIN" (also, line voltage sense). After it has started, house-keeping power for the IC comes from "VDD".

It is a current mode regulator, so it needs the output voltage...
Forum: General Electronics Technical Discussion 04-11-2022, 05:45 PM
Replies: 12
Views: 555
Posted By PeteS in CA
Re: Need new part for microwave

It's a bimetal thermal switch. It should open up if what it's mounted on gets too hot. It should close again when what it's mounted on cools.

On eBay,...
Forum: General Electronics Technical Discussion 04-05-2022, 11:59 AM
Replies: 13
Views: 662
Posted By PeteS in CA
Re: Question about MOSFET as a switch and a cap?

Assuming an N-channel MOSFET, for it to turn on the Gate must be several volts more positive than the source. The meaning of "several volts" will depend on the threshold voltage of the MOSFET....
Forum: Troubleshooting Power Supplies and Power Supply Design 04-03-2022, 10:00 AM
Replies: 14
Views: 540
Posted By PeteS in CA
Re: Aerocool cylon 700watt Atx psu

I think it's a Tiny Switch type all-in-on regulator. The "missing" pin 7 is probably the spacing between pin 8, the output MOSFET Drain, and pin 6, the Source. Whether it's literally is a Tiny Switch...
Forum: Troubleshooting Power Supplies and Power Supply Design 03-29-2022, 04:27 PM
Replies: 7
Views: 492
Posted By PeteS in CA
Re: Delta DPS400-MB, pwr_ok stays low

I'm going to guess that the pull-up resistor for the Power Good signal is on the IBM MB, and that may be the case with your "Retro-PC workhorse".
Showing results 1 to 25 of 500

 
Forum Jump


Badcaps.net Technical Forums © 2003 - 2022
Powered by vBulletin ®
Copyright ©2000 - 2022, Jelsoft Enterprises Ltd.
All times are GMT -6. The time now is 04:07 AM.
Did you find this forum helpful?