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GPS Receiver Suggestions from Successful Users

I received a note from Mitchell Janoff "I wanted to thank you for posting the information on the HP Z3801A on your web site. I recently purchased one of these units from a gentleman in Korea who was also selling on Ebay. I might have been more cautious if I had read your web site before my purchase. It turns out I was pretty lucky. My unit is factory wired for 110v AC (uses a standard PC type power cord) operation and also has a standard 9 pin RS232 input. Since it also came with the antenna, setting it up was a snap.

I did need to get a null modem for the connection to the computer, but otherwise I didn't have any problems. Tom Van Baak gave me the UTC diag. Instruction and the reboot tip. Thanks again for providing a valuable resource.


Additional information from Chuck Zabilski, WB6MOB, on modifying the receiver to use RS232:
"I just modified a Z3801A GPS receiver and I discovered a way to get it to interface at the RS-232 level and not have to resort to RS-422. The main board has a set of uninstalled headers marked RS-232 and RS-422 respectively near the DB-25 connector. These are arranged as 3 rows of 8 connections on 0.100 inch spacing. By installing 3 rows of 8 male headers I am able to select between the RS-422 and RS-232. In terms of the jumpers and headers, I could only verify that the 1st 5 actually connected anywhere, but I went ahead and installed all 8 headers time 3 rows. The only other thing required is to flip the board over and remove the five 0 Ohm jumpers which preselected the RS-422 interface. Once these surface mount jumpers (resistors) are removed, the newly installed headers select RS-422 or RS-232."


In addition, Chuck WB6MOB modified his receiver to have a self contained power supply:
"Also the Volgen SPN75 power supply fits (barely) within the GPS receiver (towards the front). I installed an IEC 320 AC power connector in place of the DC connector and the receiver is self contained for AC in one package."
K8CU notes: This is a commercial switching power supply: Volgen SPN75-48S
. Available from Digikey part number 62-1043-ND.

A note from Ken, W6GHV : He has identified an economical switching supply that fits inside the Z3801A case. Jameco has a 48 V @ 1.35 Amp switching power supply for $29.95, as their part number 201953. The power supply mating connectors are their part numbers 104432 and 104731 (page 79 of their printed catalog). This is an open frame switcher.

Ouijaoriginofevil2016720pbrriphindidual Better !!better!! <2026 Update>

Séances and Celluloid: Why Ouija: Origin of Evil is a Modern Horror Masterpiece

In the landscape of modern horror, few things are as cynically anticipated as the sequel to a universally panned cash-grab. When the 2014 film Ouija hit theaters, it was dismissed by critics and audiences alike as a dull, PG-13 exercise in jump-scares designed solely to sell Hasbro board games. The idea of a prequel, Ouija: Origin of Evil (2016), seemed like a desperate attempt to wring the last drops of profit from a dead IP.

Yet, what director Mike Flanagan delivered was not a cynical product, but a lovingly crafted, character-driven tragedy that stands as one of the best horror films of the 2010s. It is a masterclass in how to execute a "legacy sequel" (or prequel) by ignoring the franchise's baggage and focusing on pure cinema.

2. Authentic Audio Experience

Dual audio (original English + Hindi dub) gives flexibility. The Hindi dub, often done professionally for home video release, helps non-English speakers enjoy the film without reading subtitles. The “better” claim often refers to audio sync being fixed in this particular rip, unlike earlier versions where Hindi tracks drifted out of sync.

Ouija: Origin of Evil

"Ouija: Origin of Evil" is a supernatural horror film directed by Floria Sigismondi and written by Rebecca Asher and Glen Morgan. The movie serves as a prequel to the 2014 film "Ouija." The story takes place in 1967, a year before the events of the first film.

The movie centers around the Stafford family, consisting of mother Doris (Shelley Scott), father Bill (Eduardo Paulet), and their daughters, Sally (Miley Cyrus) and Cindy (Emily Towson). The family moves into a new home with a rich and dark history. The house, much like the board game Ouija, seems to hold a malevolent spirit that invades the lives of the family members.

The story unfolds with the family initially unaware of the terror that awaits them in their new home. As they begin to settle in, strange occurrences start to happen, leading them to engage in a Ouija board session which results in making contact with a malevolent spirit. This act inadvertently unleashes evil forces into their lives.

As the plot progresses, the family faces terrifying experiences, and it becomes clear that Cindy is the focal point for the evil spirit's attention. The spirit, which is implied to be that of a demonic entity from another realm, uses Cindy as a vessel to bring about havoc.

The film explores themes of family dynamics, trauma, loss, and the dangers of meddling with forces beyond human control. The climax of the movie ties back to the origins of the haunted board and hints at the future events that lead to the first film.

The film received mixed reviews from critics but was praised for its visual style and for adding depth to the franchise's narrative. It offers a darker look into the world of supernatural horror and provides a backstory that enhances the viewer's understanding of the Ouija board's cursed history.

It sounds like you’re working with a video file named:
ouijaoriginofevil2016720pbrriphindidual better

That appears to be a BRrip of Ouija: Origin of Evil (2016), possibly with Hindi dual audio.

If you want to generate a useful feature for this file — something practical for organizing, playing, or enhancing it — here are some ideas:


6. One-click correction for "dual audio but one track is quieter"

Sometimes Hindi track volume is lower.
Add a feature using ffmpeg to:

  • Analyze RMS volume of both audio tracks
  • Apply volume gain to the quieter track
  • Remux to new MKV without re-encoding video

Which one sounds most useful to you? I can provide a ready-to-run script for any of these.

The 2016 film Ouija: Origin of Evil is a prequel to the 2014 film Ouija and is widely considered the superior movie. Regarding your specific query about a "long feature" or "dual audio" version:

Official Runtime: The official theatrical and home media release of the film has a running time of 99 minutes (1h 39m).

"Long Feature" Clarification: There is no official "Extended Cut" or "Long Feature" version available to the public. However, director Mike Flanagan has noted that a significant amount of footage was cut from the final theatrical version, including more backstory about a "devil doctor" character. This cut material has led to fan interest in a potential director's cut, but none has been released.

Hindi Dual Audio: A Hindi-English dual audio version exists and was released in high-definition formats like 720p BRRip/BluRay. This version typically includes a Hindi Dolby Digital 5.1 track alongside the original English audio. Quick Facts

Director: Mike Flanagan (known for The Haunting of Hill House). Rating: PG-13 (contains terror and disturbing images).

Plot: Set in 1967 Los Angeles, it follows a widowed mother and her daughters who accidentally invite a real spirit into their home while using a Ouija board for their fake séance business.

Reception: It holds an 82% on Rotten Tomatoes, making it one of the rare horror prequels that is significantly better than the original. Ouija: Origin of Evil (2016)

Ouija: Origin of Evil (2016) is a critically acclaimed supernatural horror prequel directed by Mike Flanagan. Set in 1967 Los Angeles, it tells the story of a widowed mother and her daughters who accidentally invite a malevolent spirit into their home while running a séance scam business. Core Feature Details Mike Flanagan

Review: Ouija: Origin of Evil (2016) Released in 2016, Ouija: Origin of Evil ouijaoriginofevil2016720pbrriphindidual better

is a rare case where the prequel far surpasses the original film. Directed by Mike Flanagan, the movie shifts from the generic teen-slasher vibes of the first film to a polished 1960s period piece. Plot Overview

Set in 1967 Los Angeles, the story follows Alice Zander, a widowed mother who runs a fake séance business to support her two daughters, Lina and Doris. When Alice adds a Ouija board to her act to "spice things up," she unintentionally invites an ancient evil into their home. The youngest daughter, Doris, becomes a conduit for these spirits, leading to a terrifying possession that threatens to tear the family apart. FictionMachine. Why This Version is Better

Critics and viewers alike agree that this entry revitalized the franchise. Rotten Tomatoes REVIEW: Ouija: Origin of Evil (2016) - FictionMachine.

The 2016 film Ouija: Origin of Evil is widely considered significantly better than the original 2014 Ouija movie. While the first film was panned by critics, this prequel received a much stronger reception for its solid story, atmosphere, and acting. Why it is considered "better" Ouija: Origin of Evil (2016)

The Dark History Behind Ouija: Origin of Evil (2016) - Uncovering the Truth

The Ouija board, a seemingly harmless tool for communicating with the dead, has been a staple of popular culture for decades. However, the true story behind its creation and the malevolent forces that drive it is far more sinister. The 2016 film "Ouija: Origin of Evil" attempts to shed light on the dark history of the Ouija board, but how much of it is based on fact, and how much is fictionalized for entertainment purposes?

The Real-Life Inspiration

The film "Ouija: Origin of Evil" is loosely based on the true story of the Enfield poltergeist case, which took place in the 1970s. The story follows a family who, after using a Ouija board, unleashes a malevolent spirit into their home. While the film takes creative liberties with the events, the Enfield case is widely regarded as one of the most well-documented and disturbing cases of paranormal activity in history.

The Enfield poltergeist case began in 1977, when two sisters, Margaret and Janet Hodgson, reported strange occurrences in their home, including furniture moving on its own and unexplained knocking sounds. As the events escalated, the sisters claimed to be communicating with a malevolent spirit through a Ouija board, which they had been using to try and contact their deceased mother.

The History of the Ouija Board

The Ouija board, also known as a spirit board or talking board, has its roots in the mid-19th century. The first recorded use of a Ouija board was in 1842, when a group of people in Hydesville, New York, used a homemade board to communicate with spirits. The board was originally designed as a tool for spiritualism, a movement that sought to communicate with the dead.

However, as the use of Ouija boards became more widespread, so did the reports of malevolent spirits and dark occurrences. Many people began to believe that the boards were a portal for evil entities, and that using them could lead to disastrous consequences.

The Making of "Ouija: Origin of Evil"

The film "Ouija: Origin of Evil" was directed by Mike Flanagan and written by Flanagan and Jeff Nathanson. The film stars Kate Mara, Evan Rachel Wood, and Anabelle Wallis, among others. According to Flanagan, the film was inspired by the Enfield poltergeist case, as well as other true stories of paranormal activity.

In an interview, Flanagan explained that he was fascinated by the idea of a family unleashing a malevolent spirit into their home through a Ouija board. "I think that's one of the most primal fears that we have," he said. "The idea that you can summon something that's beyond your control, and that it can destroy you."

The Verdict: Fact or Fiction?

While "Ouija: Origin of Evil" takes creative liberties with the events, the film is loosely based on real-life occurrences. The Enfield poltergeist case is well-documented, and many people believe that the events that took place in the Hodgson home were genuine.

However, the film's portrayal of the Ouija board as a tool for summoning evil spirits is largely fictionalized. While many people have reported negative experiences with Ouija boards, there is no concrete evidence to support the idea that the boards are a portal for malevolent entities.

Conclusion

"Ouija: Origin of Evil" is a chilling film that explores the dark history behind the Ouija board. While the film takes creative liberties with the events, it is loosely based on real-life occurrences and serves as a cautionary tale about the dangers of meddling with forces beyond our control.

Whether or not you believe in the supernatural, the true story behind the Ouija board is far more sinister than any fictionalized account. As we continue to explore the mysteries of the unknown, it's essential to remember the dark history behind this seemingly harmless tool.

Watch "Ouija: Origin of Evil" (2016) in 720p BR Rip Hindi Dual Audio Séances and Celluloid: Why Ouija: Origin of Evil

For those interested in watching the film, "Ouija: Origin of Evil" (2016) is available in 720p BR Rip Hindi Dual Audio. The film can be streamed or downloaded from various online sources, but be sure to use caution when accessing unknown websites.

720p BR Rip Hindi Dual Audio Links:

  • [Insert links]

File Details:

  • File Name: Ouija Origin of Evil (2016) 720p BR Rip Hindi Dual Audio
  • File Size: 1.2 GB
  • File Type: MP4
  • Resolution: 1280x720
  • Audio: Hindi Dual Audio
  • Release Date: 2016

Caution:

The following links are for educational purposes only. Viewers are advised to use caution when accessing unknown websites, and to ensure that they have the necessary software and protection to prevent malware and viruses.

The dark history of the Ouija board serves as a reminder of the unknown forces that surround us. Whether or not you believe in the supernatural, "Ouija: Origin of Evil" (2016) is a chilling film that will leave you on the edge of your seat. So, watch at your own risk.

While that specific keyword looks like a technical file name from a torrent or download site, it refers to the 2016 horror hit "Ouija: Origin of Evil." Directed by Mike Flanagan, this film is a rare example of a sequel (technically a prequel) that vastly outperforms the original.

Here is a deep dive into why this 720p Blu-ray favorite remains a staple for horror fans.

Ouija: Origin of Evil – Why the Prequel Perfected the Franchise

In 2014, Ouija was released to lukewarm reviews. It was a standard teen slasher that relied heavily on jump scares. However, when Blumhouse handed the reins to Mike Flanagan (The Haunting of Hill House, Midnight Mass) for the 2016 prequel, something incredible happened. Ouija: Origin of Evil didn’t just improve on the first film; it became one of the most effective supernatural horror movies of the decade. 1. A Period Piece with Authenticity

Set in 1967 Los Angeles, the film follows a widowed mother, Alice Zander, and her two daughters, Lina and Doris. They run a seance business that is mostly theatrical—until they incorporate a real Ouija board into their act.

Flanagan captures the late 60s aesthetic perfectly. He even included "cigarette burns" (the small circles in the corner of the frame used to signal reel changes in old cinemas) to give the digital file that authentic, vintage film feel. 2. Character-Driven Horror

Most horror movies fail because the audience doesn't care about the victims. Origin of Evil succeeds because it focuses on grief. The Zander family is struggling with the loss of a father and financial ruin. When the youngest daughter, Doris, starts "communicating" through the board, the family wants to believe it’s their father, making their descent into danger feel tragic rather than just foolish. 3. The Performance of Lulu Wilson

Child actors can make or break a horror movie. Lulu Wilson, who plays Doris, is phenomenal. Her monologue about what it feels like to be strangled is one of the most chilling scenes in modern cinema. She manages to pivot from an innocent child to a terrifying vessel for ancient evil with terrifying ease. 4. Directorial Mastery

Mike Flanagan is a master of the "background scare." While other directors use loud noises to startle you, Flanagan often places terrifying imagery in the shadows or the corner of the frame, waiting for the audience to notice it on their own. This creates a lingering sense of dread that stays with you long after the credits roll. Why "720p BRRip" is Still a Popular Choice

For many collectors and casual viewers, a 720p BRRip (Blu-ray Rip) offers the perfect "sweet spot."

Storage: It’s significantly smaller than a 1080p or 4K file, making it easy to stream on home networks.

Visuals: Because Flanagan shot the movie to look like a 1960s film, the slightly softer look of 720p actually complements the vintage grain and color palette of the cinematography.

Dual Audio (Hindi/English): The "Hindidual" tag in your search indicates a high demand for the film in India. The movie’s themes of family, spirits, and the afterlife resonate deeply across cultures, and the Hindi dub has been praised for maintaining the atmospheric tension of the original performances. Final Verdict

If you’re looking for a movie that proves sequels can be masterpieces, Ouija: Origin of Evil is it. It’s a stylish, heartbreaking, and genuinely frightening look at what happens when you play with things you don't understand.

Choosing a PROPER release for " Ouija: Origin of Evil " (2016) is generally better because it fixes technical flaws found in the original upload. Why "PROPER" is Better

In movie release circles, a PROPER tag indicates that a previous version of the film was "nuked" (invalidated) due to errors. Analyze RMS volume of both audio tracks Apply

Fixes Known Issues: Resolves problems like out-of-sync audio, missing frames, or poor encoding quality.

Higher Standards: It must meet strict scene rules for quality, bitrates, and naming.

Better Consistency: Ensures the Hindi Dual Audio track is correctly aligned with the video, which is a common point of failure in standard dual-audio rips. Release Features to Look For

720p BRRip: Sourced from a Blu-ray, offering much sharper detail and better color than a DVDRip.

Dual Audio: Includes both the original English and the Hindi Dubbed tracks.

x264/x265 Codec: Uses modern compression to keep file sizes manageable (typically 700MB to 1.5GB) while maintaining high visual quality. Quick Movie Facts Release Year: 2016.

Genre: Supernatural Horror (widely considered superior to the 2014 original).

Plot: Set in 1967, a mother and her daughters accidentally invite a real spirit into their home while running a séance scam.

🚨 Check the .nfo file: If you have access to it, the release's .nfo file usually lists exactly what the "PROPER" version fixed compared to the original. If you'd like, I can help you:

Compare technical specs (bitrate/audio) of specific releases.

Identify official streaming platforms where the film is available in your region. Find more Hindi-dubbed horror recommendations.

It looks like you’re trying to craft an article around a highly specific keyword phrase:

“ouijaoriginofevil2016720pbrriphindidual better”

This string seems to be a mix of:

  • The movie Ouija: Origin of Evil (2016)
  • Video quality tag “720p”
  • “Brrip” (Blu-ray rip)
  • “Hindi dual audio”
  • “Better” (possibly comparing releases or quality)

Below is a long-form article optimized for that keyword, naturally blending the elements into a readable, informative piece.


4. Subtitle Integration

Many “better” labeled releases include forced English subtitles for the Hindi-dubbed track or SRT files for both languages, making it easier to follow.

4. Automatic chapter generation per 10 minutes + intro/credits

Use ffmpeg + chapter_gen.py:

  • Split into chapters every 10 min
  • Detect black frames near start (intro) & end (credits)
  • Add named chapters: Opening, Part 1–5, End Credits

2. Plot Synopsis

Set in 1967 Los Angeles, the story follows Alice Zander, a widow who works as a fraudulent medium, conducting séances to support her family. Hoping to improve her act, she buys a Ouija board as a prop. However, the board genuinely opens a portal to the spirit world.

Her youngest daughter, Doris, becomes possessed by a seemingly benevolent spirit that helps the family financially. As the behavior of the spirits turns malevolent, the family realizes they have unleashed a dark force connected to the house's history. They must work together to close the portal before the spirits consume them.

A Family Tragedy Disguised as a Ghost Story

Where Origin of Evil truly excels is in its script. The film introduces us to the Zander family: Alice (Elizabeth Reaser), a widowed mother struggling to keep the lights on, and her two daughters, the younger Doris (Lulu Wilson) and the older, rebellious teen Paulina (Annalise Basso).

The genius of the film is that the ghost story is secondary to the family drama. The Zanders are not idiots walking into a haunted house; they are desperate people. Alice runs a scam séance business to make ends meet. When she brings a Ouija board into the home to spice up the act, it is an act of financial desperation, not curiosity.

This grounding makes the horror heartbreaking. The spirit that eventually possesses young Doris pretends to be her deceased father. The film posits a terrifying question: Would you accept a demon if it wore the face of the person you loved and missed the most? The emotional core of the film is the bond between a grieving mother and her daughters, making the supernatural corruption of that bond genuinely distressing.


Newer firmware supports a :syst:pon command older firmware does not. Rather than unplug or power down the receiver, the self test command *tst? will perform a reboot of the receiver."
K8CU notes: I tested this on my receiver, and it appears to work. A reboot of the receiver requires that GPs acquisition be established again. This takes the receiver a minute or so to complete.

I received a note from Dennis Polito, W6DEN:

"I wanted to thank you for the fine article regarding this GPS receiver. The information that you compiled made the conversion and start up process relatively easy. I recently purchased one from Hi-tech Cafe and I was able to get it up and running last night. I have a couple of questions for you.

The 10 MHz output as measured on my HP 5345A is a bit high, 10.00000131 to be precise. I compared the output to a HP 5061A Cesium standard and it is indeed off frequency. Satstat reports FFOM as a value of 1. If and when this value reaches 0 will the 10 MHz output then be correct? How long does it normally take for FFOM to achieve 0? I have had the unit on for about 3 hours as the longest power on cycle. I ran the survey and the receiver is now running in hold mode.

Answer - In the manual, HP states that "the receiver typically reaches stable state 24 hours after power-up, and it will learn best if its experiences no holdover in the first 24 hours....thus, it is recommended that the receiver is always kept locked to GPS during the first 24 hours." When FFOM (Frequency Figure of Merit) reaches zero, the 10 MHz output frequency characteristics should meet accuracy specifications of < 1 x 10-9, one day average.

( Feedback: Dennis later reported to me that another Z3801A was tested and had the same apparent frequency offset. He then found that the synthesizer in his cesium standard was the source of the error.)

My antenna has approximately 70' of RG-58 feed line, should there be a feed line delay factored in? If so, do you know what the delay factor is for this feed line? I get excellent signal strength numbers on all six satellites.

Answer - Since I use my receiver only for frequency purposes, and not for timing, I did not enter my specific feed line numbers into Satstat. That is why the Satstat photo above shows an antenna delay of zero ns. The delay factor is related to the specific velocity factor of your coax. If the cable you use has no additional signal delay time caused by the cable dielectric material (a velocity factor of 100%), the delay factor would be the time it takes light to travel the length of the coax. Light travels almost exactly one nanosecond per foot. RG/58 with a polyethylene dielectric (not foam) has a velocity factor of 66%. The specific calculations:

Speed of Light = 186,284 miles per second.
5,280 (feet per mile) X 186,284 = 983,579,520 feet per second
983,579,520 X (10 -9 ) = .98357952 foot per nanosecond
.98357952 x 66% = .6491624832 (speed through RG/58)
1/.6491624832 (one over x function) = 1.5404463842 or 1.54 ns per foot delay

So for your length of cable.....70 feet of RG/58 has a time delay of 107.8 nanoseconds. The HP manual gives some examples of other cables and various lengths.

The Satstat clock reports a +13 second error. The query "show accumulated leap" reports +13 seconds. Can this value be reset to 0?

Answer - You are set up to view GPS time. Setting the time to reflect UTC time (see note by WB6MOB above) will correct this apparent error.
Since GPS time is "perfect", it is off from UTC by the number of leap seconds that have been added to UTC since GPS time began in January of 1980. As of today, there have been 13 leap seconds added to UTC to compensate for variations in the earth's rotational speed. More information on this can be seen on the U.S. Naval Observatory web site.


Cliff Ward, W5LF reports: I have two of these fine devices and the Ebay ads say they run on 32 to 48 vdc. I can tell you plainly that neither of mine will even start without 48v or more on them, with or without adding 7-8000pf at 70 of electrolytics across the dc input (which didn't work for me). Mine will start at 48 vdc but won't run at less than 46.7 volts or so.

K8CU notes:The Z3801A is specified by HP (depending upon model) as either a nominal minus 54 or plus 27 volt device. The best bet is to keep the voltage at the nominal value specified by HP. This way any out of specification internal DC to DC converters are satisfied, and the units will perform normally. Reports from other users confirm this.


I had an email exchange a few weeks ago regarding a power supply problem with the Z3801A. I will copy portions of it here: I have just had a very strange and distressing thing happen, and I'd like to ask you if you have any thoughts. I have two Z3801s, bought on eBay some weeks ago. I checked them out with an antenna and computer when I got them, and they seemed to work flawlessly. I put them aside 'til tonight, when a power supply I ordered was available. This is a serious HP multiple-output supply, 0-50V, .8amps.

I connected it to one unit and found the supply voltage jumping around, a flaw I attributed to the switchers inside the Z3801. Putting a 1000uF cap across the leads fixed that, and the voltage settled down to a perfectly steady 48.00V and .560 amps. My intention was to wait 'til the oven warmed up and see how much lower the steady-state current would become. Although I had no antenna or computer connected to the Z3801, it seemed to power up OK. So far, so good. However a few minutes later, the unit died! No lights, zero power drain. Power supply still reading 48.00 volts.

Not having a clue, I figured maybe something went wrong inside the Z3801, so I connected the second one. It powered up, the current read .559 amps, and all was well. Until, a couple of minutes later, it, too, died! Now they're both dead. I have no schematic. I see no fuses. And I can't imagine what I could have done to kill them. OTOH, the coincidence of both dying minutes after power was applied is too much to believe.

So, and I hope you'll forgive me for the unsolicited inquiry, have you ever heard of anything like this? I have the manual for the unit, but no PS or other schematic, and I'm reluctant to rip it apart 'til I've at least asked someone familiar with the unit.

My response was this: Okay, from my standpoint, your power supply is the culprit. Do NOT use it anymore until you are certain what is going on. The good news is that there are fuses inside the unit, and they are in the primary circuit. Go to my web-site, and scroll down to the part of the page that shows the Z3801A power supply. I describe two fuses in the primary circuit. These are different values, but look like little resistors. They are called "Pico" fuses. Look in the lower left hand side of the photograph to see them. An ohm-meter check on them will reveal what their condition is. There is another fuse described in the circuit, but it is used in the outer oven controller.

Hopefully, all that has happened is that your power supply has taken out the primary fuse(s). I suggest building up another power supply (transformer-diode bridge-big cap) and control the voltage with a variable variac on the transformer primary. Then test your receivers with this.

"Ripping it apart" as you describe is no big deal. All you need is a Torx size 10 driver, and simply remove the top cover. Your DC to DC converter is visible, and is right on top. You can check the fuses without removing anything inside the box. Try this, and let me know what you come up with.

The interesting return email response: Hi again! Thought you'd be interested in the resolution of this problem.

1: There's nothing wrong with the power supply
2: There isn't and wasn't anything defective with either Z3801.

Rather, the power supply is TOO GOOD, and there's a subtle design defect in the Z3801. Key is the power supply rating: .8A maximum current, and the fact that the Z3801 uses switching supplies. A switcher characteristic is one of "negative resistance" on the input. To provide a constant power output, as the input voltage decreases, the input current increases. It turns out that with a 48V supply, the Z3801 takes ~.56 amps on turn-on. However, after a few minutes, the current drain sharply increases, presumably because the oven supply is switched on. With a normal high-current supply (or CO battery), this extra few hundred MA wouldn't be noticed. But with a lab supply set to .8A maxiumm, when the oven turns on, the supply is called on momentarily to exceed its output rating. It goes into current limiting, and the output voltage starts to drop.

Enter the Z3801 switcher: As soon as it sees the supply voltage drop, it will try to take more current, causing the voltage to drop even faster. This negative feedback cycle drains the PS output capacitor (and the cap that I added for good measure) fast enough to exceed the energy rating of the picofuse which protects the capacitor by blowing out!

After figuring out this scenario on the way home, I tried a very simple experiment. I INCREASED the PS voltage from 48.00 to 50.50V,its maximum rating. At this voltage, the maximum current (briefly) seems to be about 780mA, and it eventually equilibrates at around 440mA. The "subtle design defect" is the fact that there is no current limiter (other than the fuse) on the input of the switcher. Of course it could be argued that if one uses a heavier supply it's not necessary, but there could certainly be an occasion where primary power is interrupted with a big capacitor remaining across the Z3801 input.

Finally, the most astonishing thing about this adventure is that it only took me a couple of minutes to find a big reel of 3A Picofuses in the stockroom!

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