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Lightning

Discussion in 'Electronic Repair' started by jakdedert, Jun 29, 2005.

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  1. jakdedert

    jakdedert Guest

    It's that time of year again. Yeah, I know, I know...I need whole house
    surge protection....

    I don't have it, and I got bitten fairly big time yesterday. Two TV's, Two
    VCR's, Two cordless phones, a laser printer/fax/scanner combo, and a cel
    phone charger...so far (things keep coming up dead).

    The question is: is there even any point to opening any of this stuff up? I
    mean, it was all bought second-hand to begin with, and has given me good
    service. I'll bet I don't have $250 in the entire lot...but of course
    acquiring replacements at that price involves a lot of waiting/searching for
    deals.

    I opened one of the cordless phones (the phone won't even charge..the
    handset was off hook during the strike). It appears from in-circuit testing
    that all the transistors on the board (4 of them) are suspect. Given that,
    is there any hope that the several LSI chips on board have survived?

    One VCR is acting like it has a tape inserted, although none is...shuts off
    after trying to load the nonexistant tape. The other is basically working,
    but on-board display is scrambled, and several channels seem locked into SAP
    mode (although there is no menu option for selecting/deselecting SAP), while
    the rest seem okay.

    One TV is just flat out dead, while the other--a VCR combo--has no
    picture/sound, although transport functions 'appear' to work. Everything
    affected has already been unplugged and left to unscramble itself; but only
    one piece, a Technics receiver, actually improved after that treatment.

    The expensive all-in-one HP 2300m will probably bear at least a 'looking
    into', but the rest may just be so much landfill. I don't think I can even
    trust them for spare parts.

    Whaddaya all think?

    jak
     
  2. NSM

    NSM Guest

    It's available and easy to install.

    N
     
  3. Yeah, that sucks. Once it gets past the power supply, probably not worth
    much time. And, as you say, even keeping the electronic parts is probably
    worse than useless. The motors are probably good though.

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  4. And, then the lightning strike comes in on the phone line or the cable
    tv coax or the extension cord laid out to the garden fountain pump....

    When it's a direct strike, your number is up.
     
  5. nvic

    nvic Guest

    In regards to the VCR with the malfunctioning display: what display are
    you referring to? the clock display on the front or the on-screen
    (menus, Status messages, timer prog setup, etc.)? let me know, maybe i
    can help...
     
  6. NSM

    NSM Guest

    Most strikes are induced. Whole house will help in that case.

    N
     
  7. N Cook

    N Cook Guest

    You remember the business of the Russian's military using valve/tube stuff
    well into solid state era belatedly realised to be because it is EMP
    resistant.
    Anyone know how ordinary domestic radios in the valve era fared with
    lightning strikes ?
     
  8. Chuck

    Chuck Guest

    Very well, except for an occasional power transformer, or if a long
    wire antenna was used, the rf coils would sometimes open. Chuck
     
  9. jakdedert

    jakdedert Guest

    Chuck wrote:
    I vividly remember a direct strike on our TV antenna when I was a toddler in
    the 50's. I drew representations of it on my blackboard for years; a
    cascade of dashes representing the sparks I saw falling past our front door.
    I don't know how serious the damage; but I do remember Dad replacing the
    antenna itself...and using that TV right up through most of the 60's until
    it was scrapped for a color set.

    jak
     
  10. jakdedert

    jakdedert Guest

    Thanks. I originally said 'on board' to distinguish it from 'on screen;'
    but that unit has now been determined to have survived unscathed, after a
    second round of 'disconnect/reconnect' to the AC supply.

    Upon that second round of diagnosis, I've discovered the issue with the
    phones to be a result of a damaged outboard caller ID unit. It was
    connected to only one line, but took both down. Disco'ing it fixed that
    problem...scratch another device. I opened up the cel charger today--a
    switching type. The resistor in series with the AC line is charred beyond
    recognition and both diodes immediately past that are shorted...didn't go
    any further. I'll keep the housing (nifty little unit with flip-down AC
    prongs) and the stupid Sony/Ericsonn proprietary plug.....

    The fax machine is the major loss. I detailed the aquisition of this here a
    couple years ago. Again: an HP 3200m which I purchased at auction, with a
    corrupt bios. It's showing a '79: Service Error' with the second line of
    the lcd reading a cryptic 'download_modem.O'(verload?). I'll research that
    to see if reflashing the BIOS might cure, but I'm not optimistic. The thing
    about these units is that if one section dies *nothing* works. Now I'm out
    a scanner/printer along with the fax. I learned that lesson a few years
    ago, and will never purchase such (new) again; but this one was such a good
    deal and has paid for itself already. Of course replacement cost might be
    many times my initial investment of around $65.....

    jak
     
  11. jakdedert

    jakdedert Guest

    I think it would certainly help to some degree. I had a similar (more
    severe) loss about ten years ago. I recently aquired ownership of this
    property after renting it for 17 years; so now I have much more latitude in
    replacing the antiquated knob and tube electrics.

    Neither strike was direct. The last one nailed a stately oak tree in the
    back yard (which spreads over the house and is the highest point in the
    neighborhood). This strike is as yet undetermined as to it's exact 'ground
    zero'; but the actual pulse appears to have had via multiple points of
    entry. It took out one unit connected solely to the AC, but also appears to
    have caused damage seemingly localized to the phone line and cable as well.
    In fact, based on number of devices affected, the major damage looks to be
    from the phone line (two phones--three survived--fax, caller ID). I don't
    know whether to attribute the TV/VCR damage to the AC, cable or some
    combination...probably the latter.

    Obviously, any secure whole-house protection would have to secure *all* the
    copper coming into the house. I'll be looking into that. Hopefully--some
    day--all but the AC will be non-conductive fiber...which will probably
    introduce it's own set of issues.

    And so it goes....

    jak
     
  12. NSM

    NSM Guest

    well.

    Sounds right. See http://www.smarthome.com/4860.html

    # Unlimited main breaker panel current
    # Transient surge capacity - 950 joules
    # Maximum surge current - 50,000A
    # Response time - Instantaneous

    for possible solutions.

    N
     
  13. If you have the time, the HP and the TV's, if reasonably large screen
    size. Any evidence of ground traces being burned does not bode well...

    Tom
     
  14. This wasn't lightning, but I had an experience once where I
    encountered what I believe was one phase of a 3-phase system which was
    wired to a regular 110-120 receptacle. Our entire band was plugged in,
    and all gear was solid-state except for my old 50's Fender Super. It
    was my practice to turn it on and let the tubes warm up before
    throwing the Standby switch, and when I powered on (first, thankfully)
    it emitted load groaning noises. I immediately switched it off, and
    cautioned the other guys to not turn their gear on. I don't know for
    sure what would've happened, but I'm pretty sure any SS gear under
    that circumstance without an SMPS would've immediately been toast.
    That amp also worked for many years afterwards.

    Tom
     
  15. Inty

    Inty Guest

    Argh ! If you didn't try a diagnosis you can't establish what's damaged !
    Maybe the VCR are still reparable... for the phones I think that they're
    junk, you can retain them to cannibalise components, but they're unusable.
    The celly's charger can't be repaired : it's a too small SMPS... buy a new
    one, it didn't have an high cost.

    I.
     
  16. Inty

    Inty Guest

    Argh !
    For the TVs, open them, and first control the fuse : if it's blow, change
    it. You maybe lucky ! Or, if it didn't work, or the fuse re-blows, change
    the bridge rectificator, and even the 110v filter cap and the line filter...
    if this didn't fix, you may try to change *all* the components in the power
    supply, all resistances, all caps, all inductors, the ic, all transistors,
    everything. Value if this is worth the price of the TV. This may cost from
    10 to 15 dollars. If the damage isn't only in the power supply, but has
    affected uP, EEPROM and other ICs value if they have a low cost and then try
    to change them... if they have an high cost, junk the set !
    testing

    They didn't charge but can take the line ? In this case, they're
    recuperable, but if they didn't take the line, they're junk !
    Read above.
    Hum, for the second VCR with the non-functioning display : verify that there
    are +33V to make the FPD work ! If they aren't present, try the diodes and
    electrolytic caps on the secondary of the power supply. Also try to change
    the fuseable resistors...
    Test power supply, for more info reply...
    You was lucky ;-).
    Does it turn on ? Test the PSU ! If the damage is extended on the
    mother-board you can discard it or ebay for mechanical spares that are 100%
    good.

    I.
     
  17. Choreboy

    Choreboy Guest

    In the past few years, a tree thirty feet from my service entrance and a
    tree fifty feet from my service entrance got struck. The second one lit
    up the neighborhood. I had no electrical damage either time.

    Six days ago my chimney got hit. The bolt blew masonry and shingles
    sixty feet. I was online. My screen froze with a strange tint, but
    things were fine on restart.

    I lost two stereo receivers and the control board for my furnace/ac. My
    battery-powered indoor/outdoor thermometer was "stunned". It recovered
    when I switched from F to C and back.

    My other electronics, including a shortwave plugged in with one stereo
    receiver and a TV plugged in with the other, showed no damage. One
    stereo receiver was on, and I suppose the surge took the amp. The other
    was off, and the digital controls got wrecked.

    My modem and cordless phone were fine. Across the street, the surge
    from my strike took out the neighbors' modem, satellite receiver (with a
    telco connection) and two phones. They went online six years ago and
    have repeatedly asked why they kept losing modems and surge protectors.
    I have repeatedly told them that until they bond their telco electrode
    to their power electrode (NEC 250.54) they will be vulnerable to ground
    surges. They have repeatedly ignored my advice and will continue to
    ignore it.

    I might not have lost my ac control board if I'd paid more attention to
    the above article. The furnace and the compressor are on concrete
    slabs, and I've never checked to see if their frames show zero ohms to
    my primary grounding electrode.

    Except the cellphone charger, everything the OP lost may have been
    connected to a TV cable or telephone cable. I wonder if his bonding is
    okay. I think I've read that sometimes cable TV has no local ground,
    and before you ground your end, you must isolate it from the company
    cable with a couple of baluns.
     
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