I am currently receiving broadcast HDTV on a Channel Master Model 3020
combo UHF/VHF/FM antenna. I have a rotator and also a mast mounted
antenna amplifier. I bring 75 ohm coax down and split the signal
several times.

My HD reception is usually good, but occasionally it's hard to aim the
antenna and sometimes the signal will drop out. VHF reception is very
good and I want to keep that capability.

I'm thinking that to improve my HD (UHF) reception I'd like to install
Channel Master's primo UHF antenna, the model 4228, which is a big
square "chicken wire" affair. In fact, I just bought this antenna.

My next problem is figuring out how to hook it up and still keep the
combo 3020 antenna in service for my VHF and FM stations. I could
mount the 4228 on the same mast and use a 300 ohm combiner to bring
leads from both antennas together, but will the UHF signals from the
3020 and the 4228 combine properly? Or will I get the possibility of a
phase mismatch? To solve this, can I somehow disable or disconnect the
UHF portion of the 3020 antenna and then use the 300 ohm combiner with
the 4228?

Also, if I mount both these antennas on the same mast, will they
somehow interfere with one another? I'm assuming I could separate them
by about a foot or so.

Thanks in advance for any insight on this.

Rick Sink

"Rick Sink" wrote in message
...
I am currently receiving broadcast HDTV on a Channel Master Model 3020
combo UHF/VHF/FM antenna. I have a rotator and also a mast mounted
antenna amplifier. I bring 75 ohm coax down and split the signal
several times.

My HD reception is usually good, but occasionally it's hard to aim the
antenna and sometimes the signal will drop out. VHF reception is very
good and I want to keep that capability.

I'm thinking that to improve my HD (UHF) reception I'd like to install
Channel Master's primo UHF antenna, the model 4228, which is a big
square "chicken wire" affair. In fact, I just bought this antenna.

My next problem is figuring out how to hook it up and still keep the
combo 3020 antenna in service for my VHF and FM stations. I could
mount the 4228 on the same mast and use a 300 ohm combiner to bring
leads from both antennas together, but will the UHF signals from the
3020 and the 4228 combine properly? Or will I get the possibility of a
phase mismatch? To solve this, can I somehow disable or disconnect the
UHF portion of the 3020 antenna and then use the 300 ohm combiner with
the 4228?

Also, if I mount both these antennas on the same mast, will they
somehow interfere with one another? I'm assuming I could separate them
by about a foot or so.

Thanks in advance for any insight on this.

you can try, but don't be surprised if it doesn't work as you hope. the
best thing would be to run a new feedline just for the uhf antenna.

Rick,

Assuming your amp is a combined UHF/VHF, you will want to combine the two
antennas into the amplifier through a UHF/VHF splitter or combiner. Now, any
UHF signal picked up by the VHF antenna will be ignored.

Tam/WB2TT
"Rick Sink" wrote in message
...
I am currently receiving broadcast HDTV on a Channel Master Model 3020
combo UHF/VHF/FM antenna. I have a rotator and also a mast mounted
antenna amplifier. I bring 75 ohm coax down and split the signal
several times.

My HD reception is usually good, but occasionally it's hard to aim the
antenna and sometimes the signal will drop out. VHF reception is very
good and I want to keep that capability.

I'm thinking that to improve my HD (UHF) reception I'd like to install
Channel Master's primo UHF antenna, the model 4228, which is a big
square "chicken wire" affair. In fact, I just bought this antenna.

My next problem is figuring out how to hook it up and still keep the
combo 3020 antenna in service for my VHF and FM stations. I could
mount the 4228 on the same mast and use a 300 ohm combiner to bring
leads from both antennas together, but will the UHF signals from the
3020 and the 4228 combine properly? Or will I get the possibility of a
phase mismatch? To solve this, can I somehow disable or disconnect the
UHF portion of the 3020 antenna and then use the 300 ohm combiner with
the 4228?

Also, if I mount both these antennas on the same mast, will they
somehow interfere with one another? I'm assuming I could separate them
by about a foot or so.

Thanks in advance for any insight on this.

Rick Sink

On Mon, 6 Oct 2003 20:01:28 -0400, "Tarmo Tammaru"
wrote:

Rick,

Assuming your amp is a combined UHF/VHF, you will want to combine the two
antennas into the amplifier through a UHF/VHF splitter or combiner. Now, any
UHF signal picked up by the VHF antenna will be ignored.

Huh??? If the amp amplifies both UHF and VHF then why would it ignore
VHF?? Can you explain a bit more?

Thanks,
Rick


Tam/WB2TT
"Rick Sink" wrote in message
. ..
I am currently receiving broadcast HDTV on a Channel Master Model 3020
combo UHF/VHF/FM antenna. I have a rotator and also a mast mounted
antenna amplifier. I bring 75 ohm coax down and split the signal
several times.

My HD reception is usually good, but occasionally it's hard to aim the
antenna and sometimes the signal will drop out. VHF reception is very
good and I want to keep that capability.

I'm thinking that to improve my HD (UHF) reception I'd like to install
Channel Master's primo UHF antenna, the model 4228, which is a big
square "chicken wire" affair. In fact, I just bought this antenna.

My next problem is figuring out how to hook it up and still keep the
combo 3020 antenna in service for my VHF and FM stations. I could
mount the 4228 on the same mast and use a 300 ohm combiner to bring
leads from both antennas together, but will the UHF signals from the
3020 and the 4228 combine properly? Or will I get the possibility of a
phase mismatch? To solve this, can I somehow disable or disconnect the
UHF portion of the 3020 antenna and then use the 300 ohm combiner with
the 4228?

Also, if I mount both these antennas on the same mast, will they
somehow interfere with one another? I'm assuming I could separate them
by about a foot or so.

Thanks in advance for any insight on this.

Rick Sink

Rick,

Think of the splitter that used to come with TV sets. You had the antenna
lead that had both UHF and VHF on it, which got split by the splitter behind
the TV set. The VHF signal went to the VHF input on the TV, and the UHF
signal went to the UHF input of the TV. You want to do the same thing, but
in reverse. On the splitter, connect the UHF port to the UHF antenna, and
the VHF port to the VHF antenna. The third port goes to your amp input. The
amplifier will have both UHF and VHF signals, but the UHF signal will all
have originated in the UHF antenna, and the VHF signal in the VHF antenna.
Do NOT use a 2 set coupler instead of the splitter; you will lose 3 to 4 db
of signal to noise, regardless of the gain of your amplifier. You can
probably buy these things at the Radio Shack.

Tam/WB2TT
"Rick Sink" wrote in message
...
On Mon, 6 Oct 2003 20:01:28 -0400, "Tarmo Tammaru"
wrote:

Rick,

Assuming your amp is a combined UHF/VHF, you will want to combine the two
antennas into the amplifier through a UHF/VHF splitter or combiner. Now,
any
UHF signal picked up by the VHF antenna will be ignored.

Huh??? If the amp amplifies both UHF and VHF then why would it ignore
VHF?? Can you explain a bit more?

Thanks,
Rick


Tam/WB2TT
"Rick Sink" wrote in message
. ..
I am currently receiving broadcast HDTV on a Channel Master Model 3020
combo UHF/VHF/FM antenna. I have a rotator and also a mast mounted
antenna amplifier. I bring 75 ohm coax down and split the signal
several times.

My HD reception is usually good, but occasionally it's hard to aim the
antenna and sometimes the signal will drop out. VHF reception is very
good and I want to keep that capability.

I'm thinking that to improve my HD (UHF) reception I'd like to install
Channel Master's primo UHF antenna, the model 4228, which is a big
square "chicken wire" affair. In fact, I just bought this antenna.

My next problem is figuring out how to hook it up and still keep the
combo 3020 antenna in service for my VHF and FM stations. I could
mount the 4228 on the same mast and use a 300 ohm combiner to bring
leads from both antennas together, but will the UHF signals from the
3020 and the 4228 combine properly? Or will I get the possibility of a
phase mismatch? To solve this, can I somehow disable or disconnect the
UHF portion of the 3020 antenna and then use the 300 ohm combiner with
the 4228?

Also, if I mount both these antennas on the same mast, will they
somehow interfere with one another? I'm assuming I could separate them
by about a foot or so.

Thanks in advance for any insight on this.

Rick Sink

Rick,

Think of the splitter that used to come with TV sets. You had the antenna
lead that had both UHF and VHF on it, which got split by the splitter behind
the TV set. The VHF signal went to the VHF input on the TV, and the UHF
signal went to the UHF input of the TV. You want to do the same thing, but
in reverse. On the splitter, connect the UHF port to the UHF antenna, and
the VHF port to the VHF antenna. The third port goes to your amp input. The
amplifier will have both UHF and VHF signals, but the UHF signal will all
have originated in the UHF antenna, and the VHF signal in the VHF antenna.
Do NOT use a 2 set coupler instead of the splitter; you will lose 3 to 4 db
of signal to noise, regardless of the gain of your amplifier. You can
probably buy these things at the Radio Shack.

Tam/WB2TT

OK, got it. I did not know that the splitter would automatically strip
any UHF signal off that might be combined on the lead coming from the
VHF/UFH combo antenna.

Thanks!

Rick

I think you need a "diplexer" to combine antennae.
This has inputs marked UHF, VHL-LO, VHF-HI or
whatever, and presumably includes some filters to
minimised interference from mixing signals with
different delays.
A plain splitter is broadband, so unless your antennae
are narrowband, you may get ghosts.