Re: [HCDX]: Re: Beverages
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [HCDX]: Re: Beverages
With the beverages on the Oregon Coast, I pick up a fair amount of
static and noise during exteme conditions. Not just on rge beverages,
but eben on car radios and portables. I remember 30 years ago when
driving across a bridge into Astoria where I was a college student,
during rain & hail I would pick up on the car radio a squeal across the
whole MW dial. You could even hear it under the local stations at times.
I would guess it was some kind of static buldup from the storms. We have
very little lightening around here and rarely does it ever strike
anything. I have even Dxed during a listening storm using beverages (as
a kid) with an old tube radio. Except for the noise, I could DX fine.
The AU conditions were so wild I was hear all sorts on South Pacific MW
stations all night. I wouldn't do that today, especiall with solidstate
gear. I still get the squeal across the dial at times to this day in the
Winter months mostly. It seems to be frequency sensitive though. Some
frequencies it is stronger, others not. All my antennas have home brew
matching transformers and Co-ax (RG58, 59, and RG6), so I don't get the
direct colege to the receiver which is much safer.
73s,
Patrick Martin
Seaside OR (USA)
--- Begin Message ---
To answer your questions on my comments Mauno...I can say....yes and no...I will
explain why!
With a static buildups on f.e. heavy snowfalls and hail showers...there can be
high power buildups up to 70 volts per meter ....so if you have a 300 m
beverage..the voltage can be as high as 21000 volts,but the currents floating
through the is very very low.
An ....yes...you can isolate or to say it another way..... lead it to ground when
using a balun,by this way the electrical power/current doesn't go into the
receiver...safe...yes...but not safe enough.
Always disconnect your antenna(s) when there is such conditions working
around....there is always a chance of lightning strikings!!
What regards to my ..no...you can hear the static noise...the coaxial can reduce
some of the noise,
but not all.
Another I would like to point out...after several intensive static buildups and
thunderstorms,always check the resistor in the far end....it has a tendency to be
blown out.
I also have a example on how statics can do strange things ....for several years
(before I started out with coax feed in's and resistors...) I sat dxing a early
night with snowfalls and really nasty weather outside...I had build myself a very
simple antenna switcher...single throw type switchs...this night I sat wondering
over a tic sound coming every second...I listen very close to my receivers
....nope...and finally found out it was the switcher...the static buildup was
making high power sparks between two switches...and the voltage wasn't very
pleasant to feel. If I connected the antenna to the ground wire,
the power was discharged for a while....but it sure did come back.
So do believe me when statics have high voltage buildups!!
What coax concerns...my 3 beverage antennas which is use...there is now 2 of them
that have coaxial feed in...resistor and 5 copper rods in the far end....further
on there is also a own ground system for each of the baluns...I have also a
separate ground system just 3-4 meters from the house,
but this one I would like to upgrade even..it only consists of 2 meter
copper/steel rod and a 1 square meter net with thin installation wire together
with som hen iron-net!
This is connected with a RG213 coax into the receiver(s)...which reduces the noice
1 or 2 S-units.
I should also add...that I have a high power line about 100 meters from the
house...but there is no problems with it.
I hope some of this info helps a little...
73's
Alf
Mauno Ritola wrote:
> Alf Aardal wrote:
> >2. Connecting the antenna(s) to a balun(transformer) isolates the antenna
> >electrically from the receiver,and doesnt let the statics go in to your
> >receiver either,but leads the static to ground.After all a static buildup can
> >cause up to 70 volts per meter on really long antennas.....
>
> Is that a fact? Does it really help with STATIC noise? I thought coax &
> balun is for avoiding man-made noise from the house to get in to your
> radio? During Christmas there was terrible noise, when the snow gathered on
> the wire and signals were relatively low. But I guess a good grounding for
> the radio and the other one in antenna's far end will do the same trick? (I
> have been convinced by the most of you not to use coax & balun, because I
> don't have man-made noise nearby and I can get the wires straight from the
> listening cabin).
------------------------------------------------------------------------
This is a message from Alf Aardal <alfardal@xxxxxxxxx>
to hard-core-dx@xxxxxxxxxxxxx list. To unsubscribe the list, send
"unsubscribe hard-core-dx" in mail body to majordomo@xxxxxxxxxxxxxx
For more information, please check http://www.iki.fi/rko/hard-core-dx/
or email Risto Kotalampi, risto@xxxxxxxxxxxxxx
------------------------------------------------------------------------
--- End Message ---