So why are x uH's of green wire inductance ok in the three wire case and not for a single green wire (engineering pls, not UL regs)? Grant KZ1W Advice? Honda generators put out trash as a common mode
Actually, none. Neither old or new philli uses thimbles (except for the smallest size new). I've done extensive tensile testing on 5/8" old philli with cable clips over a period of three months and w
Check out http://k7nv.com/notebook/id7.htm for an analysis. btw the Rohn pole is 0.125" 6061 wall and rated for 45G @70# per section. Never use a pole as a tram tie off or pull at an angle against th
EHS guys may still be standing after the fires described, but only if the wind didn't blow, since most of the strength will be lost at the wildfire temperatures quoted. from a wiki post "At about 550
McMaster has balls in stainless, 304, 316, and 440. 316 isn't the hardest but is the most corrosion resistant. They are what I use for rotator rebuilds. If you meant "cratered" which happens when the
Plastic thrust bearings are the way to go. Black UHMW is another great (and cheaper) material. Both UHMW or Nylon are UV susceptible but if black or GSM they should last a long time. I recently disas
I made a new base (welding grade rebar of course) and put one (LM354 not HD) up last month. A mid size Kubota (35hp) front bucket wouldn't lift it as I predicted so Western Crane was hired to raise i
Dean gave an HFTA talk at Seaside last week and I asked this question. "How far away do I not need to worry about a mountain?" His answer: "over the horizon". He showed some patterns much further out
I recently concluded testing of wire rope clamps (clips) on "old" parallel Phillystran (PS). The old PS does not work with the current PS guy grip type of termination. These tests showed that clamps
Check ebay for out of production bearings and suppliers of same. I found some for a LM354 that way. Very unusual bearing/sheave assembly marked "Boeing", so Tri-Ex must have bought a bunch of Boeing
Just remember that the loads on a temporary support can be quite large. If the support is half-way from the pivot then the entire weight that section of the tower is on that support plus the translat
I rebuilt a tired EF180C (no longer sold) which is 86' long. Many of the rivets were loose and were drilled out and replaced with cross bolts. I particularly like W6NL's advice on connecting elements
I rebuilt a tired EF180C (no longer sold) which is 86' long. Many of the rivets were loose and were drilled out and replaced with cross bolts. I particularly like W6NL's advice on connecting elements
You wouldn't do this to a "real" bearing, but I've had success sanding out the divots, or at least making them less bumpy. The balls are cheap to replace and stainless steel ones are available from M
If the CrMo is heat treated (and as hard as it should be) then all you will get is a dull blade in a portable bandsaw. A carbide tipped blade may work, but are fragile, a tungsten carbide abrasive co
The gap between the Moxon tips is less than between non Moxon elements but sufficient to clear most any guyed tower. I have one (bought) that came down from R45 via a tram and will go up on a new R65
MFJ "value (not) engineering" is one reason I decided to build the Dave Leeson W6NL Moxon from scratch. He designed for 110mph survival. Decision validated, I'd say. Grant KZ1W On 8/1/2014 9:36 AM, D
The W6NL Moxon design uses schedule 80 PVC pipe for the driven element insulation. F12 at one time did use ABS pipe since that was on my EF180C. ABS drain pipe is a bad idea since the core is foamed
R25 goes self supported to only 40'. Look at the Trylon T200-60 or US Tower MA550 mast or UST TX455. Probably about $5k, tower ($2.5k), freight ($1k+ to NY), digging , concrete, rebar. Buying new doe
If the roof is metal than ground to it and no radials are needed. If it is composite or concrete then a few feet should be ok and no radial or the antenna should be grounded to anything. (except an R