Stiffness isn't necessarily related to strength. Properly engineered structures have some amount of flex built into them. Changing the relative stiffnesses of structural members can change the distri
Didn't the cable company provide an appropriate lightning/overvoltage protection device? One would be required for the installation if it was done according the NEC. It will look like a little alumin
I've seen the transient suppressors that use a standard gas tube spark gap with a probe to the center conductor of the coax. I think they just make the dimensions such that the mismatch isn't all tha
The stuff's not corrosive, but it is a great thermal insulator, which is bad in the usual bead balun, since the common mode energy is being dissipated in the beads (or, alternately, reflected back by
And even better, there is a detailed data sheet with derating and impedances on it.. http://www.cal-av.com/baluns-EB1-ds.html I do have a question about the term "reactance"... Does this mean if I ho
Indeed.. the solenoid is almost purely inductive (except for small losses due to skin effect and finite resistivity of the shield material), so the phase should be 90.. The beads show a phase angle o
Linksys sells a "range extender" which is essentially a LNA and a power amplifier in a box that neatly mounts underneath a WAP11 (access point) and has the appropriate jumper cables. They run around
Fuses aren't a power kill, they're "overcurrent protection", designed to keep the house from burning down. Breakers or fuses, all the same, except bear in mind that for 220V, for a disconnect (not ov
what sort of adjustment speed do you need. A 8 or 16 pulse per rev disk and an optical encoder driving a suitable low impedance device (open collector type scheme) or even 8 magnets and a reed switch
The losses of the dual coax will be comparable to that of a single coax run. For lower frequencies, the ohmic losses dominate (skin effect, predominantly) over the dielectric loss (at least until you
an You bet it's a problem...one work around would be to wind your balun, then run it over a temperature cycling (put it in the oven) for a bunch of cycles, and check it.
The OTARD (over the air reception device) rules were enlarged a bit last year to include devices that transmit as well as receive, for the purposes of wireless internet connectivity. The original OTA
There are three basic approaches: 1) There is some literature in the journals on the effect of insulation on wires which was the basis of the math in the second approach 2) NEC4 (which understands in
I agree with K1TTT's comments, below.. comments interspersed.. Jim, W6RMK -- Original Message -- From: <k1ttt@arrl.net> To: <towertalk@contesting.com> Sent: Tuesday, July 29, 2003 6:30 AM Subject: Re
Mike is exactly right... Looking at loss as a dB/foot for the coax, you divide the power into two pieces of coax, so the absolute loss (in watts) will be half in each piece of coax, but you've got tw
I found the specific reference that says that OTARD doesn't help you with your ham antenna.. It is mentioned in the FCC's fact sheet, however, that derives from a footnote on page 45 (of 144) in FCC
Now I am really confused.. enough of the facile quick stuff.. time for the rigorous analysis.. stay tuned, but more facile analysis below But half the power flows through each line, no? and, half the
Once the signal is "inside" the coax, it matters not how far apart they are. The impedances are determined by the coax. However, from a spurious currents carried on the outside of the shield standpoi
100 ohms.. 2 * 50 (or 104 if RG-8X is 52 ohms.. it's probably not controlled that well anyway) They actually make coax "zip cord". I don't recall the number, and it might be more expensive than 2 RG-