Creating Durable Systems – Feedlines and Antenna Switching

Creating Durable Systems within the K9ZW Main QTH Shack is a series started with:  https://wp.me/p2XN8-1Sc

The Feedlines and Antenna Switching system can be broken down further:

• Feedlines to Skyneedle main tower with multiple antennas
• Feedline to Flagpole Vertical Antenna
• Feedline to woodland antenna box
• RX-only feedlines to RBOGs (Reversible Beverage (antennas) On Ground)
• Feedline to portable antenna test area

The needs for its final build-out, testing and commissioning include:

• Radio to Feedline Selection Point
• Feedline Selection Point to individual feedline routing to destination
• Destination selection of specific antenna in some instances (second switch level)

In way of documentation to make future troubleshooting and repairs easier the links are:

Feedlines came from DavisRF who are awesome people to work with – their website is:  http://www.davisrf.com/

Switchgear came from 4o3a who are also great people.  The direct 4o3a website is:  https://www.4o3a.com/ though my units were purchased either from Force-12, Vibroplex or FlexRadio Systems.  At the time of this writing (late April 2020) Vibroplex seems to have a pretty comprehensive 4o3a offering.

And my system is built of:

• (Hardline) RFS 1/2″ Cellflex Cable http://products.rfsworld.com/WebSearchECat/datasheets/pdf/cache/LCF12-50JFN.pdf
• (Other Cables) Belden 9913F7 Cable https://catalog.belden.com/techdata/EN/9913F7_techdata.pdf

There is more information at: https://k9zw.wordpress.com/2019/10/29/cables-for-the-new-k9zw-home-qth/

In terms of Redundancy/Backup/Failure Options:

There is a spool of Timewave LMR-400 on site, which can be pulled to replace a failure.  There is also a spool of marine grade RG6 in storage if the RX-only lines needed replacing.

By using the same 4o3a 2×8 antenna switches at both the home QTH and Island QTH, I’ve ended up with a spare unit that can be programmed to replace a single unit failure.  Of course the switches can be replaced with manual units or barrel connectors with even less flexibility.

Alternative units from Array Solutions, DX Engineering and MFJ could also be used.

73

Steve
K9ZW