I have had a request to post a summary of answers to my query about the use
of the separate Rx antenna connections on the FT1000MP (ie. for beverage
antennas, etc), so here it is. My original query is the first message below.
Vy 73,
Steve, VK6VZ
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With recent experiments using separate Rx antennas on 160m, my attention was
drawn to the facilities on my FT1000MP for using/switching such an antenna.
What I found was that the description of this facility in the FT1000MP
manual seems to bear scant resemblance to the actual implementation on the
radio!
The manual says there is a single separate Rx Antenna phono socket on the
back of the FT1000MP, whereas in reality there is actually two Rx Antenna
phono sockets - one labelled 'In' and the other 'Out'!
On the basis of past experience with rigs like the IC751A, I would assume
that the one labelled 'In' actually goes to the RX side of the radio (and is
the place to connect an external Rx antenna), whereas the 'Out' is for the
connection of an external RX, or similar. However, rather than making an
assumption, please could someone enlighten me as to the true situation.
I suspect there are others on this reflector who may be similarly
puzzled/have been puzzled in the past!
Vy 73,
Steve, VK6VZ
__________________________________________________________________________
>On the basis of past experience with rigs like the IC751A, I would assume
>that the one labelled 'In' actually goes to the RX side of the radio (and is
>the place to connect an external Rx antenna)
Correct! That's how I have mine connected.
, whereas the 'Out' is for the
>connection of an external RX, or similar. However, rather than making an
>assumption, please could someone enlighten me as to the true situation.
I believe "Out" brings the signal line from the RX so that you can
connect an external preamp for example then go back through the "In"
port. My trusty TS-930 had exactly the same sort of connections
through the Transverter connector. I used an external preamp which
would work either on the transmit antenna (from "Out" on the 930) or
a Beverage. I often switched just the preamp in when on 10 meters for
example.
_________________________________________________________________________
Hi, Steve,
Re your query about the FT-1000MP Rx Ant "In" & "Out" jacks. I don't
have an MP, but I do have a brochure for one, and there's a block diagram
in it showing how it functions.
If you want to receive on a separate antenna (such as a Beverage) than
the Tx antenna ("A" or "B"), connect the separate Rx antenna to the "Rx
In" jack and depress the "ANT RX" pushbutton just below the S-meter (next
to the "IPO" pushbutton).
Depressing the "ANT RX" pushbutton connects the "RX ANT IN" jack to the
receiver and disconnects the selected main (transmit) antenna ("A" or
"B") from the receiver.
Depressing the "ANT RX" pushbutton also connects the selected main
antenna to the "RX ANT -OUT" jack while not transmitting. The block
diagram shows that you can use this feature in two ways:
1) You can connect the "RX ANT OUT" jack to an external receiver (which
will receive signals from the selected main antenna).
2) Or you can connect it to the input of an external pre-amp (or external
filter), with the output of the pre-amp (or filter) connected to the "RX
ANT IN" jack. The pre-amp would then be used for amplifying received
signals from the main antenna.
So, to use the "OUT" jack, the "ANT RX" must be depressed. Of course, if
you use the "OUT" jack for an external pre-amp, then you'll also be using
the "IN" jack for the pre-amp, so then you can't hook a Beverage to the
"IN" jack.
If you have a separate Rx antenna that requires a pre-amp, don't use the
"OUT" jack. Hook the separate Rx antenna directly to the input of the
pre-amp and hook the output of the pre-amp to the "IN" jack, and depress
the "ANT RX" pushbutton. (Of course, the "OUT" jack can still be used
for an external receiver.)
It looks like a handy thing that the Yaesu engineers did there.
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Steve, you're right- there is no description of the "Rcv Out" jack in the
manual. The Rcv Out jack has the signal as applied thru Coax Jack A or B
(depending on which one is currently selected) available at it, when the the
front panel switch has selected the Rcv Antenna. When the front panel switch
for the Rcv Antenna isn't selected, there is no signal available at the Rcv
Out jack. This allows you to put a preamp or additional filtering in the
receiving line without having to take into account the 100watts or so of power
it might have to handle. A quick look at the schematic or a phono jack jumper
cable will verify my statements.
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You are correct. However, it can be taken further; you can take the receiver
out to a switch, put other low noise antennas on the switch, and feed the
switch into the rx ant in port. Thus you can have the transmit antenna on
the same switch with the other rx antennas, and even put a preamp in line if
you wish.
The rx out jumpered to rx in with the rx antenna switch pushed is the same
as not having the rx antenna switch pushed.
ends
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