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Old September 23rd 06, 05:16 PM posted to rec.radio.shortwave
Mark Zenier Mark Zenier is offline
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First recorded activity by RadioBanter: Jun 2006
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Default Shortwave Listener (SWL) Newbee Question - Is My Dipole Antenna Set-Up Right ?

In article ,
Telamon wrote:

A better antenna in the same space would be a folded dipole, which would
use the common and cheap 4:1 transform used with FM and over the air TV
antennas.


The set is nowhere near a 50-75 ohm input. Especially if the RF gain
isn't fully on.

Looking at the schematic of the DX-160, the antenna inputs feed a 2k
ohm potentiometer, (the RF gain control), (with a back to back pair of
protection diodes from the wiper to ground), and then are switched to
the input windings of the first tuned circuit.

Next, there's a cascode FET RF amplifier and another tuned circuit feeding
the mixer. Both tuned circuits are tuned with the main and bandspread
variable capacitors. And the input coil is tuned with an antenna trim
control, too. (There's plenty of places to mis-tune this RF amp, if the
unit seems a little deaf). Then to a mixer and a 455(?) kHz ceramic
IF filter.

I would try a folded dipole direct to the balanced A1-A2 inputs. The set
doesn't need a balun.

Or Google up RHF's posts from a year or three ago about using a room
sized loop on a ceiling or wall with the DX-160.

Mark Zenier
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