Topband: [TowerTalk] Hygain 18-HT 160m Trap wanted

[Joe Subich, W4TV]

On 7/22/2024 6:41 PM, Jim Brown wrote:

> Both the trap and the loading coils are pretty easy to build if we
> have good data and/or construction details.
The trap is nothing special.  Since it connects to the tower at the
top, it is likely resonant on 40 meters - in fact the MK-160A manual
parts list online shows: p/n 977234  Trap, 40 meter

This is the same 40 M trap used in both the Hy-Gain DP-5BDQ
(80/40/20/15/10 trapped dipole) and DP-2BDQ (80/40 trapped dipole).

The loading coil is also nothing special ... 4 turns per inch, 3" ID x 
10" long (per the LC-160Q Product Manual online).  Originally, it was
B & W coil stock - I presume it was being made by MFJ recently.

Both approaches have significant problems:

The trap results in an inverted L that is only 25 high - very low
efficiency.  The loading coil (at high power) results in high
voltage across the insulator at the bottom of the "whip" which
is a weak point (and will melt down!).

73,

    ... Joe, W4TV


On 7/22/2024 6:41 PM, Jim Brown wrote:
> On 7/22/2024 1:47 PM, browndog2344 at gmail.com wrote:
>> I see that MFJ (current owner of HyGain) still has MK-160A's for sale 
>> (~$200).
> 
> Both the trap and the loading coils are pretty easy to build if we have 
> good data and/or construction details. Hopefully, someone can document 
> them well and share the data.
> 
> 73, Jim K9YC
>