Initially, Hy-Gain developed the 14-AV vertical antenna in late 1950s.Hustler/Newtronics developed the 4-BTV in this same period.
In the early 1960s, that antenna evolved into the 14-AVS (73 magazine advertisement 1966).
By 1970, this design evolved into the 14-AVQ vertical antenna.
Here is a 2009 QRZ Thread on this older Hy-Gain AV series vertical antennas.http://forums.qrz.com/archive/index.php/t-213889.html
Those traps were known as "coffee can traps" because they were almost that big.
They were also used in the old Hy-Gain 14-AV vertical (late 1950s), the predecessor to the 14AVS.
The 14-AV used 3 traps and were known to break near the traps in high winds if they were not guyed.
Because of this the 14-AVS used only 2 traps (10 and 15 Meters) and a decoupling stub that doubled as a little reinforcement for the traps.
It really wasn't needed because the new Blue "Low Profile" traps were much stronger and had much lower wind surface area.
With the 14-AVQ they did away with the 20 Meter stub and went to a 3 trap system (for 10-40 Meters).
Al, K9XR - Tinley Park, IL
Here is an earlier eHam.net thread about the Hy-Gain 14-AV, 14-AVS, and 14-AVQ vertical antennas.http://www.eham.net/ehamforum/smf/index.php?topic=61248.0;wap2
I'm most likely the ONLY person reading this, who KNOWS what a Hy-Gain 14-AVS vertical IS!
Does yours have the "pancake style" traps? Also called coffee can and large hockey puck.
The antenna originally came with these "pancake style" traps, BUT a Retrofit Kit was produced by Hy-Gain that supplied "In-Line" traps which were much better, and did NOT require adjustment.
Inside the "Pancake Trap" (can) there is a butterfly-capacitor, whose plate must be adjusted for proper resonance, although it's recommended NOT to move it -- if these traps are still sealed.
Your 20 meter adjustment is the OUTBOARD STUB. This is a quarter-wavelength vertical, all on it's own -
merely adjust the length shorter, and it will resonate where it is supposed to!
The other bands are adjusted as follows: 10m FIRST, thence 15m, and finally 40m.
MAKE SURE THAT THE COAX FITTING ON THE BOTTOM IS ELECTRICALLY TIGHT TO THE BASE!
Use the standard radial-orientation of (2) quarter-wavelength radials for each band, although I operated mine at GROUND LEVEL (very moist earth); 12" above the surface, with NO radials... like I said, the earth was very moist.
The Hy-Gain 14-AVS grew (evolved
) into the Hy-Gain 14-AVQ model (High-Q traps), but I worked a lot of DX with my silly old vertical and a SWAN 500C.
Tom, WØEAJ - Denver, CO USA