Some of the changes in grounding standards that have been mentioned (10 ft. ground rods vs. 8 ft,; 2/0 AWG copper ground leads vs. 6 tinned copper, etc.) are from the latest revision of the tower spe
ARRL sells Ham Radio Magazine on CD-ROM <http://www.arrl.org/catalog/?category=CD-ROMs#HRCD> Michael Keane K1MK k1mk@alum.mit.edu _______________________________________________ _____________________
Bill, Rights? Rights! We got no stinkin' rights! Seriously, if PRB-1 did actually confer "rights," then it would be a much better situation for us hams. Because then, someone might be successful in r
The assumption that an individual ray will follow a different path when moving left-to-right than right-to-left is what shouldn't make sense. As you shoot individual rays outward from the antenna and
Ahhh, there's a conceptual issue. In terms of geometric optics and ray tracing, a ray is assumed to be infinitely thin That's a ray bundle or a wave. That's physical (or wave) optics. HFTA is based u
Because there was a sporadic-E opening over SW Europe which was sufficiently intense and widespread to link up with the F2 opening to NW Africa One of those less than typical occurences that often go
YUp, it sure is valid. :-) Physical (wave) formalism is completely accurate everywhere but tends to be computationally very tedious when thew wavelength is small compared to the physical scale of the
Yaseu and Kenwood use the DIN-8/262 for the Band Data connector 73, Mike K1MK Michael Keane K1MK k1mk@alum.mit.edu _______________________________________________ ____________________________________
You definitely want to use a non-corrosive type of RTV. The general purpose RTV you'll find at the local hardware store is most likely to be an acetoxy cure RTV which releases acetic acid as a by-pro
That's correct. A two-part RTV is needed for use in enclosed spaces or when used as a molding or potting compound. Because the curing proceeds from the outside in, the cure time for a one-part RTV se
Yes, it was Karl Jansky (discover of radio noise from the cosmos), although Jansky's array rotated on tires from a Ford Model-T in a wooden track. It was comparatively lightweight consisting mostly o
North Brandford was never a 70 mph wind zone under the earlier "fastest mile of wind" measure for basic wind speed (EIA/TIA-222-E; ASCE 7-88); North Branford was a 85 mph fastest mile of wind zone. P
The station whose operators glow in the dark :-) Note the location and why this woodpecker site went QRT ;-) 73, Mike K1MK _______________________________________________ ____________________________
Not really. Mechanically the configuration represents a 50% increase in wind area (and an significant increase in weight) over simply tilting a conventional yagi design at 45 degrees to the horizonta
No, virtually never circularly polarized. The general case for a 100% linearly polarized wave that propagates through the ionosphere (a magnetized plasma) is for the wave to be converted into an elli
It's not that the ionosphere preferentially converts a vertically polarized wave into a primarily horizontally polarized wave. In general the ionosphere doesn't do anything like that. It's that the i
I can't recall ever having seen this bit of folklore written down anywhere. Does anyone know a source? Just my curiosity. FWIW, the phenomenon of "skywave" fading was first studied by Bell Labs, RCA,
Increasing the current while maintaining the distribution of current along the antenna does not produce "gain" provided that the applied power is held constant. Directive gain can be realized only if
I can't post from where I'm at... up in VT. Pse re-post this for me? First, you're right about the Bell Labs work of the 30's. I read the original papers, in proceedings of the IRE, in the engineerin
According to its spec sheet, a 3590S-1-501 is unsealed against water (IP40). A 3590S-3-501 (plastic bushing) or 3590S-4-501 (metal bushing) variants are sealed against a water jet from any angle (IP6