Hi Bill, W0BTU has an excel spreadsheet on his site that will calculate both differential and common mode impedances for a bi-directional Beverage based on AWG, height, spacing, and dielectric. http:
P.S. Please correct - reversible Beverage, not bi-directional. Sorry. -MF Hi Bill, W0BTU has an excel spreadsheet on his site that will calculate both differential and common mode impedances for a bi
Hi Bob, I have been buying my Erico CAD supplies online from Gordon's Electric Supply because they seem to carry the full line of product, are reasonably priced, and have excellent customer service.
The Comtek model ACB-4-A series units could be used to drive a 2 element phased array by connecting the 2 verticals separated by a quarter wavelength on ports do connect a 50 ohm dummy load to the du
Hi Paul, I've been working on a similar project so I'd like to share some ideas with you. First off, you are probably already aware that when you get up into the 12 dB RDF range the patterns generall
Hi folks - need some help. A shortened 160m vertical ground plane antenna is cut and tested for a resonant frequency of 2.24 Mhz. The antenna is matched near perfectly to 50 + 0j ohms at 1.85 Mhz usi
Sorry - I should have provided more info. I'm trying to assess the impact of this TX antenna on the performance of some other receive antennas by modeling the site. I am thinking I can get a somewhat
Thanks David - trying to model what impact the TX antenna will have on other antennas at the site. Matt KM5VI the power absorbed from the external excitation to be transferred to the load. What are y
Hi John, I have some MMANA and 4NEC2 files on various iterations of 40 Moxon conversion of a Mosley S402... I switched to MMANA for this project since NEC2 engine does not seem to handle abrupt right
All of the boxes I have seen are OEM Hub City, Series W300 I believe. They are not too hard to rebuild if you are so inclined. Replacements were about $400 last time I priced one. Your gear box shoul
Just wanted to echo Rick's comment. I have 4 older crank-ups (2 Triex and 2 UST) and all have had pulley bearings go dry over the years. The only failures I have seen develop with gear boxes have bee
Hi Bob thats some great information & if OK Ill echo some similar experience. Just a word of caution to the readers on the reflector - be careful ordering KP8 bearings off of ebay I have five here at
Don't feel alone Chuck, sometimes I walk from one room to the other and wonder what it was I came in the room for... as to your question, was it Remote QTH ? - https://remoteqth.com/six-to-two-antenn
Hi Bob, I have a W51 vintage 1967. On this tower there are no rotor plate tabs on the legs. The rotor plate is drilled in each corner and uses (3) wedge lock arrangements. Each wedge lock was fabrica
Hi Joe, Replacement pulleys should be available from Taj Towers. Be forewarned they are not inexpensive. If you search this archive there are a number of past posts on reconditioning pulley bearings.
strap v.s. using stranded wire or copper braid (tinned or untinned)? --jeff Wb7aht Hi Jeff, I feel that wide copper strap is an excellent choice because of its low impedance and outdoor durability.
Hi Dick, Sorry for the confusion, silver solder is only my slang. More accurately, I am using silver-copper brazing alloy - 80% copper, 15% silver, and 5% phosphorous. Melting point starts at 1190F a
Hi Ray, Although the 61.5 dimension seems odd, it appears to be correct. Note that the 1.25" diameter sections of each element become progressively shorter with each successive element. Shortening D1
To my knowledge, the original loading wires on my EF240x are stainless steel. Matt KM5VI antenna. In the past I have rebuilt/repaired the original F-12 wires with Aluma-weld 12GA.If my memory serves
I'm finally making some progress towards installing my 80m 4-square and looking for some advice before I finalize the installation. Is anyone out there using the Comtek system tuned for 3.650? Does i