Well, put up a new inverted-L antenna - 30 feet up a tree, 60 feet
across horz and over the house rooftop (nowhere else to go!), base ~20
feet from house. Using a winradio 9:1 unun matcher at the base, *not
yet grounded*. In fact, so far none of the RF chain on this antenna
is grounded. So far, so good - noise level *fairly* low (lower on
almots all freqs than my DX-Ultra), AND signal strength on most bands
roughly the same, varying depending on the band. One good thing I do
notice is that on strong MW stations, he antenna does *NOT* reveal a
60 Hz background hum like the DX-Ultra does - I consider this a good
sign. The far end is about 25 feet from the higher-tension power
lines out back, and the near end is about 15 feet from the low-tension
lines in front. Next steps -

1 - Ground the 9:1 unun
2 - Bury the coax from house to base of antenna (about 18 feet
underground)
3 - Install RF isolator (Either Radioworks or Wellbrook AFI5030) at
the house with or without a ground stake connection, depending on what
works the best.

Have not had great reception so far this week, so no chance to really
give it a workout.

Further reports to come. Thanks, guys, for all the input so far!

On 01/31/2011 11:55 AM, bpnjensen wrote:
Well, put up a new inverted-L antenna - 30 feet up a tree, 60 feet
across horz and over the house rooftop (nowhere else to go!), base ~20
feet from house. Using a winradio 9:1 unun matcher at the base, *not
yet grounded*. In fact, so far none of the RF chain on this antenna
is grounded. So far, so good - noise level *fairly* low (lower on
almots all freqs than my DX-Ultra), AND signal strength on most bands
roughly the same, varying depending on the band. One good thing I do

notice is that on strong MW stations, he antenna does *NOT* reveal a
60 Hz background hum like the DX-Ultra does - I consider this a good
sign. The far end is about 25 feet from the higher-tension power
lines out back, and the near end is about 15 feet from the low-tension
lines in front. Next steps -

1 - Ground the 9:1 unun
2 - Bury the coax from house to base of antenna (about 18 feet
underground)
3 - Install RF isolator (Either Radioworks or Wellbrook AFI5030) at
the house with or without a ground stake connection, depending on what
works the best.

Have not had great reception so far this week, so no chance to really
give it a workout.

Further reports to come. Thanks, guys, for all the input so far!

It's a rule that putting up a new antenna causes bad dx space weather.
Like washing your car makes it rain.

On Jan 31, 4:13*pm, dave wrote:
On 01/31/2011 11:55 AM, bpnjensen wrote:









Well, put up a new inverted-L antenna - 30 feet up a tree, 60 feet
across horz and over the house rooftop (nowhere else to go!), base ~20
feet from house. *Using a winradio 9:1 unun matcher at the base, *not
yet grounded*. *In fact, so far none of the RF chain on this antenna
is grounded. *So far, so good - noise level *fairly* low (lower on
almots all freqs than my DX-Ultra), AND signal strength on most bands
roughly the same, varying depending on the band. *One good thing I do
notice is that on strong MW stations, he antenna does *NOT* reveal a
60 Hz background hum like the DX-Ultra does - I consider this a good
sign. *The far end is about 25 feet from the higher-tension power
lines out back, and the near end is about 15 feet from the low-tension
lines in front. *Next steps -

1 - Ground the 9:1 unun
2 - Bury the coax from house to base of antenna (about 18 feet
underground)
3 - Install RF isolator (Either Radioworks or Wellbrook AFI5030) at
the house with or without a ground stake connection, depending on what
works the best.

Have not had great reception so far this week, so no chance to really
give it a workout.

Further reports to come. *Thanks, guys, for all the input so far!

It's a rule that putting up a new antenna causes bad dx space weather.
Like washing your car makes it rain.

....or like a new telescope eyepiece means cloudy weather :-D

On Feb 1, 1:48*am, bpnjensen wrote:
On Jan 31, 4:13*pm, dave wrote:





On 01/31/2011 11:55 AM, bpnjensen wrote:

Well, put up a new inverted-L antenna - 30 feet up a tree, 60 feet
across horz and over the house rooftop (nowhere else to go!), base ~20
feet from house. *Using a winradio 9:1 unun matcher at the base, *not
yet grounded*. *In fact, so far none of the RF chain on this antenna
is grounded. *So far, so good - noise level *fairly* low (lower on
almots all freqs than my DX-Ultra), AND signal strength on most bands
roughly the same, varying depending on the band. *One good thing I do
notice is that on strong MW stations, he antenna does *NOT* reveal a
60 Hz background hum like the DX-Ultra does - I consider this a good
sign. *The far end is about 25 feet from the higher-tension power
lines out back, and the near end is about 15 feet from the low-tension
lines in front. *Next steps -

1 - Ground the 9:1 unun
2 - Bury the coax from house to base of antenna (about 18 feet
underground)
3 - Install RF isolator (Either Radioworks or Wellbrook AFI5030) at
the house with or without a ground stake connection, depending on what
works the best.

Have not had great reception so far this week, so no chance to really
give it a workout.

Further reports to come. *Thanks, guys, for all the input so far!

It's a rule that putting up a new antenna causes bad dx space weather.
Like washing your car makes it rain.

...or like a new telescope eyepiece means cloudy weather :-D- Hide quoted text -

- Show quoted text -

aka as Murphy's Law !

Do you run with RF gain all the way up? I don't. I use a lot of AF gain
and turn the AGC off and ride the RF gain (use that for a volume
control). That gets the noise way down (until somebody flips an
incandescent light switch and the "pop" goes through my brain).

I did my deep urban DXing on a 2010 (on a 30' umbilical) and an R390-A
(120' random wire connected directly to back of radio). Biggest power
lines overhead at right angle to random wire. The R390-A's what got me
hooked on pro grade receivers.

On Feb 1, 9:04*am, dave wrote:
Do you run with RF gain all the way up? I don't. I use a lot of AF gain
and turn the AGC off and ride the RF gain (use that for a volume
control). That gets the noise way down (until somebody flips an
incandescent light switch and the "pop" goes through my brain).

I did my deep urban DXing on a 2010 (on a 30' umbilical) and an R390-A
(120' random wire connected directly to back of radio). Biggest power
lines overhead at right angle to random wire. The R390-A's what got me
hooked on pro grade receivers.

It depends on the situation. I only rarely turn off the AGC, but I do
ride the RF Gain quite a bit, partly because of this effect you
describe and partly because it really helps the S-AM work properly
(People complain about the Icom R-75 S-AM, even with Kiwa mods, but I
can eliminate virtually all selective fading with the RF Gain set
properly). However, I will give the method you describe a shot.

How did those powerlines affect your reception?

On Feb 1, 8:58*am, RHF wrote:
On Jan 31, 11:55*am, bpnjensen wrote:

Well, put up a new inverted-L antenna - 30 feet up a tree, 60 feet
across horz and over the house rooftop (nowhere else to go!), base ~20
feet from house. *Using a winradio 9:1 unun matcher at the base, *not
yet grounded*. *In fact, so far none of the RF chain on this antenna
is grounded. *So far, so good - noise level *fairly* low (lower on
almots all freqs than my DX-Ultra), AND signal strength on most bands
roughly the same, varying depending on the band. *One good thing I do
notice is that on strong MW stations, he antenna does *NOT* reveal a
60 Hz background hum like the DX-Ultra does - I consider this a good
sign. *The far end is about 25 feet from the higher-tension power
lines out back, and the near end is about 15 feet from the low-tension
lines in front. *Next steps -

- 1 - Ground the 9:1 unun

- 2 - Bury the coax from house to base of antenna
- (about 18 feet underground)

You can use 1/2" Polyethylene Tubing to Buryhttp://www.dripdepot.com/1045
your Coax in if you don't want to use PVC Pipe.
*.
Seal the Tubing ends with one of these.http://www.touch-n-foam.com/products.php
*.
- 3 - Install RF isolator (Either Radioworks or
- Wellbrook AFI5030) at the house with or
- without a ground stake connection,

Usually you should try and get this Ground Rod
were the Coax is coming out of the Ground; and
as close as you can get it to were the Coax is
about to enter the House.
*.
- depending on what works the best.
-
- Have not had great reception so far this week,
- so no chance to really give it a workout.

Then things can only get better.

- Further reports to come.
-*Thanks, guys, for all the input so far!

Post It When You Hear Them ) ~ RHF
*.
*.

Good idea on the tubing. Since I already have the PL-259s on the
cable, I may go for 3/4" or 7/8" ID tubing (they should snug through
that size tube, IIRC). I already have the 8' ground stake in at the
edge of the foundation, so it's practically plug and play if I ground
that RF isolator. I was thinking of using CoaxSeal for the tube ends,
since I have a mess of it.

Question - does the additional Poly tube around the coax diminish the
capacity to provide (presumably useful) inductive ground for the
buried cable? If the coax is not "entubed", does the covering break
down in soil? I have RG8X for the run...PVC coating IIRC.

Bruce

On 11-02-01 11:22 AM, bpnjensen wrote:

Question - does the additional Poly tube around the coax diminish the
capacity to provide (presumably useful) inductive ground for the
buried cable?


Seems to me that anything resembling an inductive ground would be a bad
thing. The inductive coupling effect would vary completely with the
frequency of the signal, proximity, length, etc. Not good.

Don't settle for anything less than a real, lowest possible impedance,
honest to G_d, mechanically connected ground. I usually smear the wire
connection and electrode with vaseline after having sandpapered them.
Then do your clamping. A plastic cup inverted over the end of the ground
rod will keep the rain out of the joint.


mike

On 2/1/11 12:41 , m II wrote:
On 11-02-01 11:22 AM, bpnjensen wrote:

Question - does the additional Poly tube around the coax diminish the
capacity to provide (presumably useful) inductive ground for the
buried cable?


Seems to me that anything resembling an inductive ground would be a bad
thing. The inductive coupling effect would vary completely with the
frequency of the signal, proximity, length, etc. Not good.

Don't settle for anything less than a real, lowest possible impedance,
honest to G_d, mechanically connected ground. I usually smear the wire
connection and electrode with vaseline after having sandpapered them.
Then do your clamping. A plastic cup inverted over the end of the ground
rod will keep the rain out of the joint.


mike

Or you can wrap it with CoaxSeal. Teflon tape works very well,
for this, too.

On Feb 1, 10:41*am, m II wrote:
On 11-02-01 11:22 AM, bpnjensen wrote:

Question - does the additional Poly tube around the coax diminish the
capacity to provide (presumably useful) inductive ground for the
buried cable?

Seems to me that anything resembling an inductive ground would be a bad
thing. The inductive coupling effect would vary completely with the
frequency of the signal, proximity, length, etc. Not good.

Don't settle for anything less than a real, lowest possible impedance,
honest to G_d, mechanically connected ground. I usually smear the wire
connection and electrode with vaseline after having sandpapered them.
Then do your clamping. A plastic cup inverted over the end of the ground
rod will keep the rain out of the joint.

mike

Well, that's not quite what I meant - I am sorry if I was unclear.

IIRC, there is nothing at all wrong with burying a cable, and in fact
it helps to keep the RFI away from the run, as well as keeping the
outer braid near the earthen ground and helping to bleed away currents
travelling along the braid. That is what I was asking about - whether
a poly tube would lessen this desirable effect.

I have every intention of grounding the 9:1 unun, presuming it will
enhance performance (if it does not, I'll disconnect it). If
necessary, I'll also install the RF Isolator and try it both grounded
and ungrounded.

I had never heard that it was necessary to keep a solid mechanical
ground water-free, although I guess I can see the value. I don't
understand what vaseline does - just protect against corrosion? I
doubt if it would help the electrical connection.