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Originally Posted by Bigbear
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Yes. The last time I measured one, it performed well.
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Thanks rabbit for the diagram. Now the only problem is finding a UVSJ. All the links I find lead to discontinued products.
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They are getting hard to find. Solid Signal is out and mjsales.net is out. There are some on Amazon and ebay. Antennas Direct still has them:
https://www.antennasdirect.com/store...Combiners.html
Inside the Antennas Direct UVSJ housing:
MCM also has one, but I have received mixed reports about its reliability. Maybe I'll have to order one and test it.
http://www.mcmelectronics.com/product/33-2230
If it gets any worse, we will have to make one like in the GE 34792 Attic Antenna:
I have used the conventional terms for top and bottom of the board. The top is where the components are mounted and the bottom is where the ground plane is located. In actual use, the coax connector faces down.
The GE 34792 Attic Antenna includes a REAL UVSJ, not shorting stubs, to keep the UHF and VHF signals separated before combining. Each section of the antenna has its own balun. The UVSJ and the well designed reflector are responsible for the good performance of this antenna.
Here is a circuit of a UVSJ by SM0HX (amateur radio callsign for a ham in Sweden). The UVSJ UHF/VHF Separator-Joiner belongs to the filter family of Diplexers. All UVSJs are Diplexers, but not all Diplexers are UVSJs; Diplexer is the more general term. A HLSJ is also a Diplexer, but for VHF-Low and VHF-High.
The UHF highpass filter section has 3 series capacitors and 2 shunt inductors. The VHF lowpass filter section has 3 series inductors and 2 shunt capacitors.
Here are the curves for the Radio Shack UVSJ:
Original post in RCA ANT751 thread:
http://forum.tvfool.com/showpost.php...1&postcount=40