[Milsurplus] [MRCA] RBA RBB RBC receiver multicoupler

[Ray Fantini]

Think the only issue may be that any wide band video amplifier may work for this but you want to be careful with the fact that they are designed to feed into a 75 Ohm load and may do weird things in terms of response when feeding a high impedance load such as the antenna input of some of those old receivers. You may want to hang a 75 Ohm resistor across the antenna input of the receiver to make it appear as a 75 Ohm load to the distribution amplifier. Also watch out to make certain that nothing exceeding a couple volts enters the amplifier because if something like a local AM station over dives the input you will see distortion on other signals.
I have tons of 75 Ohm BNC to BNC and BNC to UHF cables that were left over from the analog days of television , modern Serial Digital TV (SDI) requires different 75 Ohm cables with different BNC connectors for High Frequency response so all the old analog cables have been pulled out of service and although I have given away lots and thorn out lots still have stacks of 75 Ohm TV cable and will bring it to Aberdeen or if your planning on being anywhere sooner so you have a lot of pre-built 75 Ohm stock for connecting things.
Myself I have a couple radios but still use a patch panel and also have a switching network for selecting antennas because most of the antennas I have are cut for a band like 80, 60 and 40 meters and you will find that receivers do perform better when paired with antennas cut for that band.

Ray F/KA3EKH

From: mrca-bounces at mailman.qth.net [mailto:mrca-bounces at mailman.qth.net] On Behalf Of JEFF CICCONE
Sent: Sunday, December 16, 2018 3:51 PM
To: milsurplus at mailman.qth.net; Military Radio Collectors Association <mrca at mailman.qth.net>
Subject: [MRCA] RBA RBB RBC receiver multicoupler


Folks

I have been fortunate to have this nice receiver lineup however I am using an 3 position antenna switch to make the connection from my rf bnc antenna patch panel



I saw an article written by a british ham about using an Extron DA2 RGBHV wideband video distribution amp in lieu of rf multicouplers for my 3 navy receivers



http://gm1sxx.blogspot.com/2018/01/the-poor-mans-receiver-multicoupler.html



 Has anyone tried this ?   Those units are always on ebay and are inexpensive. I wonder how well they handle weak signals, nearby transmitters, IMD etc? I oredered one and will let everyone know how it performs



What about using Extron Ultra-Wideband Matrix Switchers for RGB and Stereo Audio as a crossbar switch to route and select multiple receivers to multiple antennas?  I realize they cannot be used for transmitting.



By the way I echo the comments about the magnificent beast RBC.  Its smooth tuning , its squelch/silencer and noise limiter circuits really work. The audio filter in the sharp mode is great for crowded CW signals.



Jeff KG2BZ
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