Connecting 2 different antennas on the same mast

[mikekohl]

I just wish that I has kept some of the negative traps that I came across while working in cable years ago ! Ih ad traps that took out all channels above 13, 2-6, cable channels 61 and up, I even had traps that would only pass FM! One system had a premium FM service that could be ordered by businesses on order to have music without commercials, a primitive version of XM I guess.

I found some on Ebay, maybe, I will use them to include another UHF in order to receive Raleigh all the time.

Did you look at the drawing that I attached to post #12 and the explanation in #13? All you need is three UVSJ combiner/separators, two F59T terminators (all Pico part #s) and some jumper cables. This will keep interaction between the outputs of both antennas to a minimum on the bands that you do not want.

 

[miguelaqui]

Did you look at the drawing that I attached to post #12 and the explanation in #13? All you need is three UVSJ combiner/separators, two F59T terminators (all Pico part #s) and some jumper cables. This will keep interaction between the outputs of both antennas to a minimum on the bands that you do not want.

Yes, thanks, but my goal is to combine antennas , not only to use the VHF, but also to use the UHF channels.

My next question, since I have purchased a VHF/UHF combination to replace the VHF only antenna, Would it help to have the VHF/UHF combination antenna on top and have the UHF only on the bottom? The most that I can get them apart if 7 feet. I cannot get them on the same tripod and have them over 8 feet part. So, if the low VHF is on top, would that have less interference the if it were 7 feet below the UHF?

 

[mikekohl]

Yes, thanks, but my goal is to combine antennas , not only to use the VHF, but also to use the UHF channels.

My next question, since I have purchased a VHF/UHF combination to replace the VHF only antenna, Would it help to have the VHF/UHF combination antenna on top and have the UHF only on the bottom? The most that I can get them apart if 7 feet. I cannot get them on the same tripod and have them over 8 feet part. So, if the low VHF is on top, would that have less interference the if it were 7 feet below the UHF?

The drawing shows you how to effectively limit the signals from the combo antenna pointed at channel 3 to VHF only, and the UHF antenna to UHF only. If you want to gain added UHF coverage from the VHF/UHF antenna pointing at channel 3, go to the first UVSJ device and remove the F59T terminator as pictured. Connect this UHF output to a 2-way VHF-UHF rated splitter via one of the output ports on the splitter. Then the splitter port input connects to the UHF in on the 3rd UVSJ device. The other splitter output should be fed from the 2nd UVSJ device, UHF output, with the F59T terminator remaining. Note that this will reduce your UHF signal levels at least 3.5 dB from both antennas. You must decide if having that other direction hardwired in combo and mixed near the antenna is worth the loss on both UHF antennas. Otherwise run the UHF out of the U/V antenna to a second wire downstairs. Then do not use the 2 way splitter as a mixer, and connect the UHF antenna output to the UHF port of the first UVSJ and then to the 3rd UVSJ pictured.

Second question: Test with only the combo VHF-UHF antenna on top of the mast....logic usually gives you less noise if a VHF antenna is higher off the ground. Then connect the UHF antenna in place below to a test TV and see if its presence affects the field of the ch 3 reception from combo UV antenna. If not, connect the filters system as suggested.

 

[miguelaqui]

I ended up buying a new antenna to point towards Roanoke, Antennacraft, c490, I prefer antennas that do not have the 75-300 ohm transfer built-in because , should it go bad, you have to order a special part. My CS-1100 would get hardly any UHF, which was odd. there must be something built-in that thing to knock them out because the CS-600 , I had one about 5 years ago, would pick up some, many more UHF channels. I later replaced the cs-600 with the cs-1100 because WBRA was unstable on the CS-600.

By the way WBRA comes in at 85% and looks great! I do have a drop out here and there, but it is much better. I also can point the antenna towards Durham and get WTVD without dropouts!

I used Mike's diagram, however, when I combined the UHF only, which is currently pointed at Raleigh, WEST 13 is so powerful that it comes in on that UHF antenna and the SUVJ was not strong enough to knock it out, so although the signal strength was 100%, it would drop out.

So, I found someone who sold negative traps at a a very decent price! I got their last mn-3, and also bought a negative trap for 13. The negative trap was able to knock the channel 13 out of that second antenna. I also purchased some traps I found by looking around. I have channels 25-29 trapped on the Roanoke side in order to insert 27 and 28 from Raleigh. I also have a low-pass 600 mhz trap to knock out any interference that could be coming in from the Roanoke side onto channel 48 and 49. Oh, I also found someone on EBAY who had some cable traps, so I took one that took out 24-72 on CATV in order to trap channels 14-21on UHF, so that channel 17 and 18 would pass without interference.

I know that people on here do not like positing links to websites that are not sensors, so , if anyone needs some negative traps, I will share with you where I got mine. I really think it is the only way to effectively combine 2 antennas. Also, if more channels go VHF, those of us who like to combine 2 antennas on one line, will need to trap the channels.

Now, let's add in the Greensboro locals! I just wish I could get more traps for UHF channels.

 

[Mr Tony]

you can post a link as long as it isnt for something illegal

 

[miguelaqui]

http://www.atvresearch.com/MNtraps.aspx