BNC Splitter - 2 antennas into one?

Status
Not open for further replies.

AOR-262

Member
Joined
May 10, 2016
Messages
319
I've got an AOR LA-400 Indoor Magnetic Loop Antenna which has a female BNC connector at the rear.

I'm using an Icom IC-R8600 which has two cables -- one is for HF between 100kHz and 30MHz and the other cable is used for receiving between 100kHz and 3GHz.

Can I connect the two cables using a BNC splitter (see image below) or should I continue to use a seperate antenna for 100kHz - 3GHz?
 

Attachments

  • BNCSplitter.jpg
    BNCSplitter.jpg
    18.1 KB · Views: 461

ScannerSK

Member
Joined
Mar 6, 2005
Messages
1,449
Location
Weld County, Colorado
This setup also ties the circuity of both radios together which can have an adverse reaction on the reception of some receivers. I would suggest trying it and verifying one or the other receiver is not having an adverse reaction (degraded sensitivity).

Shawn
 

prcguy

Member
Premium Subscriber
Joined
Jun 30, 2006
Messages
16,979
Location
So Cal - Richardson, TX - Tewksbury, MA
You only need to connect your loop antenna to one of the input connectors on the 8600 and I would recommend the 100KHz to 30Mhz port to leave you a VHF/UHF option for the future. If you use a purpose made splitter (Wilkenson or other type) to divide the signals between two receivers or two connectors on one radio, you will loose at least half your signal into the receiver.

The splitter you show is not an actual power splitter but a T adapter and that will have even more loss because its got no impedance matching circuitry inside.
 

rbrtklamp2

Member
Premium Subscriber
Joined
Dec 8, 2005
Messages
867
Location
Dupage County, Illinois
If you can find them as they have been discontinued the RF Systems SP3 was the only two way splitter I ever found to work well and it covered 10 to 2500 MHz. It was a passive splitter that just workd great. I have 3 or 4 laying around some where also Stridesberg multi couplers do very well. You may want to call stridesberg as they do custom set ups as well they built me a triplexer for vhf-uhf-700/800 and I also use two active stridesberg multi couplers an 8 port and a 4 port that work amazingly well. As I said above none of these options are cheap but they work about 100 times better than a uninsulated plain old T connector.

Sent from my SM-N910V using Tapatalk
 

AOR-262

Member
Joined
May 10, 2016
Messages
319
Ok, so for those of you familiar with the 'new' Icom IC-R8600, there are a number of connectors at the rear for connections to different antennas. Due to my location I am using an indoor antenna -- the AOR LA-400 Magnetic Loop. This actually gives me great reception on HF. So what I have is two cables, both UltraFlex 7, 2m long, both terminated with male BNC sockets. One cable is connected to the 100kHz - 30MHz socket and the other cable connected to the 100kHz - 3GHz. Obviously I can't connect and use both cables at the same time, hence asking if it is possible to use a splitter (as pictured in my first post) so that I can use/connect both cables at the same time -- as with the IC-R8600 you can select which antenna you want to use. Even if both cables were connected at the same time, the IC-R8600 only uses one antenna at a time -- so both couldn't even be used together if I wanted to.

Am I right in understanding from all the replies so far that I'm probably best keeping the AOR LA-400 just for HF (below 30MHz) and for above 30MHz I'm using the second or main antenna socket which is a simple mast antenna for general receiving.
 

plughie

Member
Premium Subscriber
Joined
May 22, 2016
Messages
35
Location
Coastside, CA
I'd suggest a switch rather than a splitter. If you really. want to go the splitter route, you may be able to build a bandpass filter at the frequency split point for your radio, but you'd still have the issue of connecting the receiver modules to each other, and that could have unanticipated results.
 

jonwienke

More Info Coming Soon!
Joined
Jul 18, 2014
Messages
13,409
Location
VA
There's also the diplexer/duplexer option which would (if you get the right one) send the correct frequencies to each input on the radio and isolate the radio inputs from each other to prevent cross-interference.
 

JamesO

Member
Joined
Jan 22, 2003
Messages
1,814
Location
McLean, VA
Am I right in understanding from all the replies so far that I'm probably best keeping the AOR LA-400 just for HF (below 30MHz) and for above 30MHz I'm using the second or main antenna socket which is a simple mast antenna for general receiving.

Keey the LA-400 for 30MHz and below, get another antenna for 30MHz+. Even if you are going indoor, just something like a Larsen Multiband mobile antenna with some form of ground plane.

Using a BNC will probably do unpredictable things and hurt the receive on either antenna input. For such a high cost receiver, do not cheap out on a decent antenna. If you need an amplified antenna, consider a decent LNA . Search my user name and the term Mini-Circuits,I have a few threads on a decent LNA, but you DO NOT want the LNA right at the radio, if you do this, you will likely need an attenuator, 10 dB at a minimum.

Try to get the 30MHz+ antenna somehow outside even if it is outside of a window.
 
Status
Not open for further replies.
Top