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181
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eHam Forums / Misc / RE: What's with the value of unbuilt Heathkits?
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on: November 02, 2012, 10:15:54 AM
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all the excitement must have gone out of the mortgage CDO^3 business, I guess, and this is the new tulip craze.
AC5UP must cry himself to sleep every night thinking about all the garages of BH Green he's dumpstered. some may say he's just nostalgic for an easy target, but really, he just wanted to have spent more time maligning every one before the back flips, nothin' but clank in the tank.
a lot of drift and intermittent signal goes away if you tighten the screws, but he won't admit it.
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183
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eHam Forums / Elmers / RE: Radio Repair Classes
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on: November 01, 2012, 10:08:28 AM
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if you were in the Twin cities, the Pavek Broadcasting Museum regularly has classes on restoring the old stuff of the 20s and 30s.
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184
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eHam Forums / HomeBrew / RE: Mounting electrolytic capacitors
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on: October 31, 2012, 01:30:53 PM
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I made several one-gallon tank processing lines for color film by supporting the film tanks in Plexiglas (perspex in the UK), and 24-hour epoxy was my mainstay. since these systems were in a temperate water bath, the quick-set stuff separated, ate chemicals, and died quickly.
I haven't gone over a 1600 WVDC tension, but in my Signal-One project, I have mounted each filter cap of the B++ bank by its screw terminals on a 1/16 thick piece of epoxy/glass circuit board stock, and that to the chassis. mount those in a plexi frame, and you ought to avoid flash-overs. I would have barrier strips epoxied between the caps for additional flash-over protection if you're going over 3000 volts, just because.
one thing to consider about surrounding sheets of plexi across the middle of a capacitor... if it reverses or shorts and blows up real good, restricting the expansion of the cap body could lead to additional physical damage elsewhere.
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188
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eHam Forums / Amplifiers / RE: Centrifugal tube blower question.
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on: October 29, 2012, 02:32:45 PM
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only way you can have overcooling with room temp forced air is if you blow the front panel off and the tube out of the socket. we can get to 40 below in my neck of the woods, so I'd not use outside air supply 
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190
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eHam Forums / Boat Anchors / RE: Yo................ Vincenzo.......................
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on: October 29, 2012, 10:16:12 AM
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backstroke. wear a nice wool sweater to prevent cramps.
myself, I would gas up the car and drive west with the insurance policies and photo albums in the trunk, and the credit cards in the pocket. after the second refuelling, find a room and watch the weather channel.
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191
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eHam Forums / Computers And Software / RE: Boat Anchor computer parts
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on: October 27, 2012, 12:12:44 PM
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in that era, there were a lot of manufacturer-specific power supplies, drive mounts, sometimes goofy cables inside computers, and Compaq was one of the oddballs. the hard drives were ATA-1 parallel, almost the old Shugart specs. and just try to find a set of Compaq mounting rails these days!
his best bet is Craiglist or eBay, but there are some boneyard dealers out there. a Google Shopping search for the individual parts may be a good thing to try.
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192
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eHam Forums / Elmers / RE: Lightning Protection For The Home?
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on: October 25, 2012, 12:16:18 PM
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direct lightning strikes on a powerline will explode "pole pig" transformers. I saw two flamed by a strike once driving by the U as it happened. wakes you up.
so protection from a direct strike? nope. not within a house.
protection from a nearby surge (induced overvoltage) can be had by taking the first two positions on the breaker panel into a surge protector through the recommended breakers. power utilities used to push whole-house protection by installing varistor packs inside the meter cabinet, but not any more.
were you to get a licensed electrician to install arc-overs on an intermediate pole between the utility drop and your service mast, down to a fantastic ground mat, and then install smaller arc-overs at the mast itself, beef up the house ground by a factor of four or so over code recommendations, and then surge at the panel and at each sensitive device, you might have a fighting chance.
even broadcast stations sometimes get the finals roached and the RF cabinet scorched by tower strikes, despite everything there being ground except the inner conductor of the hardline, and despite stout protection at the phasers for the antenna pattern. at my telco, if there is lightning in the area, nobody works on The Frame or in the cable spreader room by order. doesn't matter if there's a nuclear war in progress, you stay teh hell out of the frame, spreader, and coil rooms.
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193
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eHam Forums / Elmers / RE: Can you recomend a Digital Multimeter and supplier?
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on: October 25, 2012, 12:01:02 PM
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for initial poking around, if you have a Harbor Freight near you, get one of the $3 throwaway meters. that is perfectly good for very casual work by anybody.
got my Beckman (d) at a local parts house (d) 40 years ago. got my Fluke at Sears about 8 years ago for $80. got my Triplett 300 series old-school meter (1950s series) off Fleabay a year ago for higher voltage than 1000 VDC. dual-trace storage scope off Fleabay. pretend freq counter from Radio Shack about 12 years ago and still using it as a secondary frequency readout.
if you need a cap/inductance meter, get the AADE kit for about $80, it whales the competition.
maybe you can detect a pattern here... anybody can sell you something new for more money than you have. if you are making a living from it, and need calibration like W8JI, you are going to have to go there, or to a known reliable metrology/used equipment supplier that has the ability to calibrate to NIST-traceable standards.
otherwise, when you need a piece of equipment, look all over. hit the web. if possible, get something locally you can test to see if it works. otherwise, cleanest machine close yo your price level, wherever it is. hamfest, fleabay, craigslist, whatever.
HAM is Attic Greek for "cheaper than a hillbilly."
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194
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eHam Forums / RFI / EMI / RE: Cause for concearn?
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on: October 24, 2012, 11:04:43 AM
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the blue cores in old computer power supplies are IF range, 100-800 KHz, they should swamp anything above audio with a few turns. I've had good luck with those for a while, and the price is right. otherwise, open up the speaker cases at the weld line and put .01s across the input, speaker, and power leads.
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195
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eHam Forums / Misc / RE: Help!
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on: October 24, 2012, 11:01:24 AM
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the Lord is merciful, we just don't always recognize his ways and times. may he comfort you both, and in time, welcome her and restore you.
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