John KK9A More commonly known as 0.141" semi rigid (vs 0.085 and 0.047.. there's even tinier ones, and a bigger one ) The center conductor is copper clad steel, so the copper is carrying the RF, at l
Jim, I appreciatted your point of view. Do you think RG402 is good to build chokes at HF on FT240's ? That depends. I don't think the loss is really an issue - it's a short length in a choke. In a ch
On 3/18/21 9:19 AM, Byron Tatum wrote: Just a note -- The actual semi-rigid cable (silver plated copper tubing outer conductor 0.141" OD) that is being discussed RG-402 has an equivalent in a "con
On 3/18/21 11:36 AM, Michael Tope wrote: When using the solder-soaked braided coax, bear in mind that it if you flex it enough the solder starts to crack. Often you'll see the solder first crack in t
You can point the antenna at the sky and support it somewhat off the ground and get fairly close (the back element is somewhat detuned) John KK9A I have 3 antennas on a 10' mast sticking a total of 8
If you can do modeling, try modeling dipoles for the bands where you are concerned about interaction, with a generator in only one of them. Open the View Antenna window. Then compute the far field re
On 4/1/21 6:28 AM, N4ZR wrote: Just as an aside, I was once (too long ago) State Department desk officer for Zambia, during a major slump in copper prices, and saw first-hand the devastating effects
I have a need for a temporary set up of a run that is 300 feet from the operating position shack/controller to the top of the tower controlling a Ham 4 rotator. The final set up with be a run of 700
The capacitor is not a starting capacitor. The Hy-Gain motor requires a phase shift between windings to run (a capacitor run motor). The direction of the phase shift determines which direction which
I'm using the Green Heron Everywhere wireless system for my antenna switching and rotor controls (RT-21's). The RT-21's are off my operating desk and sitting on a shelf at the antenna entrance wall.
On 4/9/21 1:06 PM, Dennis W0JX via TowerTalk wrote: I have a similar question. I have pulled copper 1/2" and 3/4" water pipe out of the ground after several years and have found that the surface of t
On 4/12/21 2:14 PM, GEO Badger via TowerTalk wrote: John, I suggest you contact your school's governing body and municipal people. This needs to be a professional install, no jenkie ham install. Whil
A couple nice remembrances in this month's IEEE Antennas and Propgation Magazine. https://ieeexplore.ieee.org/document/9392874 (https://doi.org/10.1109/MAP.2021.3061863) https://ieeexplore.ieee.org/d
At least the plugs are good for 100k miles thanks to emissions requirements. Presumably, you'd combine it with something like a timing belt replacement. It could have been like a 70s Chevy Monza whic
Lots of color and tracer choices as well. I've bought blocks from them, no rope. It's kind of like buying coax - sure you *can* buy coax at Home Depot... But you're better off going to a cable dealer
I'm looking for an off the shelf transient/noise filter for 12V (yeah, 14.4 or 13.8V) The application is that there's motors and relays running off the 12V bus, which is noisy, but I have stuff needi
Chuck W5PR yes - but it's unclear if they have the transient clipping aspect - Esp the sort of generic "noise filter" - most equipment designed for automotive use (i.e. radios, amps) has transient
Are you thinking LT3045 - that's orders of magnitude better than I need. And it will blow up with a 50V transient on the input. _______________________________________________ _______________________
probably around an amp or so. The application is that there's motors and relays running off the 12V bus, which is noisy, but I have stuff needing a cleaner 12V and 5V (getting 5V from 12V is easy wi
On 5/12/21 8:46 AM, Richard (Rick) Karlquist wrote: I would point out that the LT3045-1 has provisions built into it to combine multiple instances of the chip to provide max current that is a multipl