Re: [Elecraft_K3] Splitting ACC port on K3 to 4 devices


Randy Farmer W8FN
 

I have a similar arrangement that I use as an ACC splitter to distribute the appropriate signals to my microHAM MK2R+ SO2R controller, my KPA500 and my XV144. It's been in service for a couple of years and works quite well.

I did exactly what you propose. I used a 4-position VGA switch from cablewholesale.com (P/N
40H1-03604 -- currently $19.01) modified as you suggest. I removed the switch and all internal wiring and wired only the necessary lines to each of the jacks from the I/O connector. If you are interested, I can send a pdf file of my drawing for the modified box and the interconnect cable to the K3.

You're right to be concerned about RFI on these lines. I have a bunch of antennas crammed into a very small lot and therefore lots of common mode RF running around. I had previously been using a bunch of Y connectors and experienced some weird problems, such as the K3 turning off its power when I transmitted on 30 meters. By putting all the wiring in a metal box and bonding the hoods of the DE15HD connectors to the box chassis and the return lines in the cable I was able to operate using the KPA500 on all bands with no RF problems. That's not to say that your installation might not require some ferrites; you just have to experiment.

Hope this helps.

73...
Randy, W8FN


On 12/23/2016 3:49 PM, ny4i@... [Elecraft_K3] wrote:
 

Due to what seems like every device I have wanting to use the ACC port on the K3, I need to split out the single connector on the radio to 4 connectors. I have real Y cables and this works fine, but the problem is that Y cables seem to grab on to other cables like Velcro and makes the rat's nest of cables worse by adding to the tangling.


I had a thought to use a simple 4 way VGA switch that basically has 5 jacks on it. PLEASE NOTE I KNOW THIS IS NOT STANDARD VGA. I am just thinking about using the box as it already has the pins wired to the back of the connectors. I will also REMOVE the SWITCH as this is not about switching—just using the box. (Sorry about the caps, but I wanted to be clear).


Has anyone done this? My plan is to just take each wire from the four different jacks and wire them to the 5th and connect them together (all pins 1 together, all pins 2 together, etc). I would either use two terminal strips or just solder the 5 wires from each pin together and heat shrink them. I was also thinking about putting ferrites over each wire but I'm not sure about the need for that.


I believe this would keep the cabling simpler as I can run the box to the side of the rig and just hook each accessory to it. I could just make a box with 5 connectors on it but honestly I can get these boxes cheap enough and it has the wires and connectors already.


I would be most interested in feedback from anyone that has hooked this many ACC devices together and how you did it.


In case anyone is wondering, the devices are:


FSK Interface (W3YY)

RemoteRig Interface

SPE1.3 amp

Top Ten Devices antenna selector (needs band data).


Regards,


Tom NY4I


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