Email Detail

HTTP 200 OK
Allow: GET, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "url": "https://mailman.amsat.org/hyperkitty/api/list/[email protected]/email/CJFSTVHOJ734LUZU37OE37RFTMNE4GN2/?format=api",
    "mailinglist": "https://mailman.amsat.org/hyperkitty/api/list/[email protected]/?format=api",
    "message_id": "[email protected]",
    "message_id_hash": "CJFSTVHOJ734LUZU37OE37RFTMNE4GN2",
    "thread": "https://mailman.amsat.org/hyperkitty/api/list/[email protected]/thread/O24KS2WDFPGKAMORPNZ5BUQUZ46ALBOX/?format=api",
    "sender": {
        "address": "stanw1le (a) verizon.net",
        "mailman_id": "cde59a7de6874af3b354fb231df89b4c",
        "emails": "https://mailman.amsat.org/hyperkitty/api/sender/cde59a7de6874af3b354fb231df89b4c/emails/?format=api"
    },
    "sender_name": "Stan, W1LE",
    "subject": "[amsat-bb] Re: 18 el cp yagi",
    "date": "2010-01-21T19:23:28Z",
    "parent": "https://mailman.amsat.org/hyperkitty/api/list/[email protected]/email/O24KS2WDFPGKAMORPNZ5BUQUZ46ALBOX/?format=api",
    "children": [],
    "votes": {
        "likes": 0,
        "dislikes": 0,
        "status": "neutral"
    },
    "content": "Good Afternoon Bob,\n\nSealing may not be the answer. There are many ways water/moisture can enter.\n\nWater ingress can happen at gaskets, coax penetration points, DC \npenetration points,\nconnector flanges, mounting screws, cover screws, etc. Coax can even \n\"hose\" water inside.\n\nI suggest limiting the moisture entry AND allow it to drain out the \nbottom. This vent hole will\nalso allow the pressure to equalize, inside vs. outside.\nIf the enclosure breathes there is no pressure or vacuum buildup inside.\nVent hole can be small, just big enough to keep the bugs out. ~1/8\" is \non the big side.\nLet gravity work for you, put the vent hole on the lowest point.\n\nOne scenario includes a hot summer day and the air inside the sealed \nenclosure expands.\nA thunder storm comes along with much cooler temps and rain. The \nenclosure is cooled and doused.\nA vacuum builds up inside and any moisture is sucked in thru any and \nevery possible entry.\nThis vacuum may exist overnight > 8 hours, so it has a long time to \"work\".\nThe moisture  and acid rain starts to corrode everything inside.\nElectricity tends to accelerate the corrosion.\nWith a functioning vent hole, the sucking and blowing is controlled and\nno significant differential pressure from inside to outside.\n\nSo, what is the solution in a rain/wet environment ?\n\nLet the item breathe, allow air to circulate.\nKeep the rain/snow from falling onto the item, cover it up.\nIf you use an enclosure be sure to vent it.\n\nAvoid dissimilar metals that will only corrode, no plated steel hardware \nor phono connectors.\nUse sealed/potted relays.\n\nFor items outside where weight is not a problem, I will design a \nconnection point so I can put a\nbucket or waste basket over it to keep the rain off. An open bottom, so \neverything can breathe.\nThe plastic container must be UV proof. A black plastic waste basket of \ndifferent sizes is my favorite.\n\nMy old KLM 22 element 2M Xpol has an open polarity select PCB on the \nantenna boom,\nbut I sealed up the relay and I removed all plated steel hardware and \nconnector, direct solder wires.\nThen I gave it all a few coats of a clear coat spray.\n\nDo not use RTV that smells like vinegar (acetic acid),it only \naccelerates corrosion.\nI have used the 3M 5200 series sealants with success.\n\nMost of the Landwehr mast mounted preamplifiers directly exposed to the \nweather will leak.\nProbably why they are no longer on the market and have sought other \nbusiness opportunities.\n\nDocument performance so you can compare later test results.\n\nStan, W1LE    FN41sr     Cape Cod\n\n\n\n\nBob- W7LRD wrote:\n> Hello \n>\n> I am refurbishing a 18 element CP yagi.  I am not sure of the manufacturer.  I opened up the relay switching box and found a lot of moisture (Yes I live near Seattle) in the box.  Lots of yuck and rust, on non stainless steel hardware..  The 12V connector is a simple phono plug, which should never be used outside.  Before I reinvent the wheel has anyone been here before?  Replace the phono plug, sealing everything.  In the past I have used a material called 3M5200, a marine sealant, nasty but almost permanent.  Suggestions please. \n>\n>\n>\n> 73 Bob W7LRD \n>\n> Seattle \n> _______________________________________________\n> Sent via [email protected]. Opinions expressed are those of the author.\n> Not an AMSAT-NA member? Join now to support the amateur satellite program!\n> Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb\n>   \n\n",
    "attachments": []
}