Building a RCA Bus to Allow Several Radios to Trigger an Amplifier

My friend George W9EVT has a fairly unique hamshack.

Most of the hundreds of radios are easily usable, but he keeps Eight radios on the ready.

The things we do to get a tower in

At our new QTH we’ve been hard at work – actually a whole team has been hard at work – getting the site ready for the first tower.

First a tower site had to be selected.  Topography, trees, and access were special considerations.  Vern K9EME has been hard at work cutting down unneeded trees once the site was picked, and processing the felled trees into firewood.

Assembling a Receive Preamp for a Yaesu DR-1X Repeater

Yaesu DR-1X repeater installations I’ve been able to look at have mostly had an added Receive Preamp added to help the RX side of the DR-1X better match the TX side.

Dave N9JDZ assembled the Preamp in use at the Washington Island WI9DX 2m repeater, and pointed me in the right direction to assemble one for the 2m repeater I am sponsoring.

The preamp module

 

Adding Ethernet Lightning Protection to the K9ZW Shack

Adding Ethernet Lightning Protection to the K9ZW Shack

 

Based largely on FlexRadio System Community web posts and an a web-article by Al NN4ZZ (http://www.nn4zz.com/FLEX6700.htm#Ethernet_Lightning_Protection) I’ve added an Ethernet FiberOptic Isolation for my hardwired Flex-6700 at the home QTH.  The Island QTH is on a WiFi extender so it is using that wireless break in cabling to achieve the same benefits, though I do expect to use FiberOptic Ethernet from the main station to the tower service shed for remote operation of equipment at the tower base.

The whole idea with isolation is to reduce the vulnerability of the on-board Flex-6700’s Ethernet adapter to stray static or electrical charge energizing a CAT6e cable, and as an added benefit decreasing the possibility of that cable picking up any stray RF or somehow coupling.

Basically there are three parts, an Ethernet Cable to Fiber box, a Fiber cable, and a second Fiber to Ethernet Cable box at the other end of the Fiber.

Ethernet CAT6e Cable to Fiber Isolation Setup

There are lots of sources for the gear to make the jump, and I selected an eBay vendor recommended to me for the Ethernet CAT6e to Fiber full duplex interfaces. With the variety I selected you need a properly configured pair (one an “A” and the other a “B”) to work.

Cables I picked from Amazon, as the original eBay cable vendor never delivered the cables ordered, which is okay (except they charged me) as I made a mistake ordering Siamese-Paired Fiber Cables which fits a different type of gear. What I needed was single cables.

I picked http://www.ebay.com/itm/151827507443 which is a matched A & B pair “10/100Mbps Ethernet to Single mode Fiber Optic Media Converter Transceiver- 25KM” set.

The cables are https://www.amazon.com/gp/product/B00E6OMK68 “Gino brand, 2 Pcs Simplex Single Mode SC to SC Male Fiber Optic Patch Jump Cable Yellow 2M” cables.  You only need one cable per pair of Ethernet to Single mode Fiber Optic Media Converter Transceivers.

(I bought two cables and two pairs of transceivers, as I usually buy a second set of components for projects like this as backups).  One setup cost me $45.50 (or $91.00 if you consider the spare set as true backups).

Seems a very low cost to do both the RFI mitigation and EMP/ESD protection adding Fiber gives.

There are a lot of other vendors and possible components. Though I have NOT been able to find one, I have wondered if a dedicated all-in-one isolation unit exists?  Maybe one of our hobby’s network gurus knows?

[EDIT – as a reader reminded me – don’t forget to protect the power supply inputs to the radio end of the transceiver pair, as it presents a way to energize the cable CAT6e jumper that plugs into your radio!  I have small items like this somewhat protected by a small UPS and further by a protected power strip, but maybe that isn’t even enough?   Thanks David for the reminder!]

73

Steve
K9ZW

K9ZW Northern Station – The Tower and the Antennas

K9ZW Northern Station – The Tower and the Antennas

The Tri-EX/Tashjian TM-370HD Skyneedle is here at a friend’s trailer yard, where we will do some light refurbishment (scrape and paint some light tin parts that are showing surface rust) and fit the Alfa-SPID RAK Rotor, while we wait for the new base and a few added accessories to arrive.

Here are a few pictures of the tower being removed from storage and transported to my friend’s trucking yard:

Crane lift of the TM-370HD

A bit about the TM-370HD – this is a motorized 70 foot tubular tower that has some pretty impressive numbers.

I have a full set of engineering calculations and the wind loading they cite is roughly five times what my array will be, and perhaps 35 times the weight load is available.

Not certain if the numbers they provided are after application of the designer’s safety factor (would presume so, as they were done for code compliance rather than product engineering) so the ultimate wind loading and weight bearing is truly impressive.

Initially going up is a SP7IDX Hexbeam HD Mark II antenna currently in production, and a W9INN Half-Sloper which I had on the ready.

The Hexbeam will cover 6m to 20m and the Half-Sloper will carry onwards 20m to 160m.

I thought I had another Tennadyne T-8 antenna locally sourced, but the present owner decided he didn’t want to sell it even though he’d just advertised it. I’d been interested in having both the LPDA and Hexbeam up to do some A/B comparisons.

Karl and Norman at Tashjian Towers Corporation have been super as usual.

They have in production a new base for me, and I am adding the work platform (tower already has the ladder) which will allow me to do 98% of service work without a lift.

That the work platform will make an awesome birdwatching and other outdoor pursuit platform hasn’t escaped me either! It is quite likely that it will also open up a way for my getting very high speed internet to this QTH, as aDSL isn’t going to quite cut it for remoting a full Flex-6000 based station.

There are a lot of logistics to go – I have verbals from the professional help to get the base in and the tower up, and I have access to a DitchWitch to bury the conduits needed. ( want to run the power separately from the coax feeds and other control wiring.)

I even have some nice touches to add features, like a set of industrial/maritime intercom units so one will be at the tower and the other in the shack.

73

Steve
K9ZW

Adding a 4o3a SSC XL Station Genius to the K9ZW Shack

Working with an evolving slightly complex station, AND wanting to using the LAN-Remote features of SmartSDR V1.4 with the Flex-6700 requires some planning – plus some electronics help!

Not point in reinventing the wheel when really sharp mins have created just the missing pieces to integrate my station.

Enter the 4o3a SSC XL Station Genius

4o3a SSC XL Station Genius – overview

The SSC XL allows control of Antennas, band-pass filters, 4-square antenna systems, beam stacks, beverages, Six Packs, rotators, RS-232 devices and more, per the website information.

4o3a SSC XL Station Genius – Front

Force12 expands further saying it is easier to say what you cannot control.

The main unit seems to have enough connectors to hook up to about anything:

403a SSC XL – Rear Panel

An outboard Relay Board called the SCC-OM controls the various devices:

403a SSC XL – Remote Module

Mine just arrived and I am digesting the the manual as I get ready to implement.  As a plus the device is said to be FlexRadio System Maestro ready!

LINK:  http://www.4o3a.com/index.php/products/station-automation/ssc-xl

LINK – USA Distributor Force12: http://www.force12inc.com/products/station-genius-ssc-xl-by-4o3a.html

73

Steve
K9ZW