Wait a minute, I thought ladder line was never supposed to be run through or over a metal surface?  Also what about running the ladder line through the wall with all those other cables, won’t that unbalance it?  Yes, ladder line should be run along unconductive surfaces as much as possible and if it does cross over metal (ie, a rain gutter),  it should run at perpendicular angles for as short a distance as possible.  Once the ladder line attaches to the arrestor, we recommend using two equal lengths of coax to run the remaining distance to the shack/tuner.  Use the center conductors of the two coaxes, and join the coax shields together at both ends.  Grounding the shields in the box can also be done.  These coax lengths need to be equal in length and as short as possible.  Since it is no longer ladder line at this point, the same losses that are attributable to the type of coax you are using now apply.  Keep it short, and remember that coax losses at HF frequencies is low.

In the pic above, ladder line attaches to the screw terminals on the left side with spade connectors.  On the right, the RG-8X-LL coax center conductors also use spade terminals for a positive connection to the arrestor.

Ladder line grommet

$24.95

Now a slick method to get ladder line into an entry panel box.  Laser cut rubber grommet and stainless steel surround provides a good seal in the box as well as making an easy to use entry for 450 ohm twinlead.  (Coax will also fit through the slot.)  The Morgan M-309 arrestor can be used to protect this line (also available below).  Please note that this is considered an installed accessory in our entry panel and junction boxes.   If ordered without an entry panel, the parts come as shown above and customer is responsible for installation and punching the correct size holes in whatever entry point they are using. 

10-12 ga. wire, #6 screw, yellow vinyl.

This will fit:      one 10-12 awg wire

                        two 14 awg wires

                        three 16 awg wires

14-16 ga. wire, #6 screw, blue vinyl.

This will fit:      one  14 awg wire

                        two 16, 18 awg wires

                        six 22 awg  wires

Models Available:                                                                                                   

M-309, Balanced line arrestor     1kw, 1-30 MHz

M-308, Single open wire arrestor     1kw    1-30 MHz         

M-309H, Balanced line arrestor     3kw, 1-30 MHz

M-308H, Single open wire arrestor     3kw    1-30 MHz                                                                              

For transmitting or receiving applications using open-wire fed systems in parallel balanced lines, these arrestors use our patented technology in larger housings with insulated terminals. These units are constructed in metallic aluminum chassis cases.

Model 308 is designed for use with open single wire systems such as tuned longwire antennas and random wires added with antenna tuners. It is compatible up to it’s design power rating with a wide variety of input impedances / reactances ranging from about 300 ohms to 600 ohms  Like all arrestor protection units these circuits are designed to be ground-mounted and should be installed close to earth entry point connections for best results.  M-308H is the 3kw high power version, comes in a 4x4x2.5” plastic NEMA box.

Model 309 is designed for use with open wire balanced feed systems. It is compatible up to it’s design power rating with a wide variety of input impedances / reactances ranging from about 300 ohms to 600 ohms  Like all arrestor protection units these circuits are designed to be ground-mounted and should be installed close to earth entry point connections for best results.  Compatible with both split capacitor type antenna tuner and balun output stages common in modern antenna tuning products.  M-309H is the 3kw high power version, comes in a 4x4x2.5” plastic NEMA box.

Price:

$76

$62

$86

$72

All units use toroid inductors and present near dead DC short on antenna side of arrestor, constantly draining feedline wires of static and any developed voltage potential feedthrough breakdown voltage from input ports to output ports 4,000 to 6,000 volts. Arrestor units may be placed anywhere in the feedline at ground level without serious change in tuning, but small change may be detectable due “to small” increase in total feedline length caused by size of arrestor case & circuit.  Models 308 and 309 series all rated for frequency range 1-30 MHz, non-DC continuous through ports, polarized.  Units 308 & 309 are constructed in aluminum cases measuring (HWD) 11/2″ x 2″x 3″. Units include a 3 page owner’s manual.