BNC Splitter - 2 antennas into one?

[AOR-262]

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?

 

[ScannerSK]

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]

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]

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]

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]

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]

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]

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.