Yes Rob, my TX vertical feedpoint was closer to 7 ohm before it being
transformed to 50 ohm by means of a auto transformer style bottom coil and tap.
I have used a big fat relay with massive silver contacts, (it was used in a UPS
to switch battery banks) but with the actuator coil wires fed tro
Actually, if you have a quarter wave driven element and you are
disconnecting it at the feedpoint, your relay concern shouldn't be
voltage so much as current. Fast switching and large contact surface
is more important than voltage handling.
73
Rob
K5UJ
_
Searchable Archives: http
HI Pete,
I use Russian B1B vacuum relays for all RF switching, for high power 160m
switching B2B vacuum relays are recommended. Hope you can get them there.
Good luck.
>Вторник, 10 декабря 2019, 16:31 UTC от N4ZR :
>
>Now that I've determined that my transmitting antenna must be
>disconnected,
Thanks everyone who responded - I think I know enough to proceed.
I had wondered about the need to open the shield side of the coax - I
have 16 turns of RG-400 on a Type 31 core right at the base of the
inverted L. If the darned rain/snow ever stops, I think I'll
temporarily re-connect the sh
The need to disconnect the feedline shield is to block common mode signals.
A K9AY approved **EXCELLENT** common mode block (not a regular "balun" with
likely awful blocking on 160m), or (GASP) an isolation transformer will
take care.
In the case quoted, with the coax center contductor opened, the
Pete,
See RF parts.com, search vacuum relay VC2T-13.2. SPDT will allow you to
change your mind about what state you want with no voltage to winding. And
you will not need to buy a 24 volt power supply.
Rated 12 kV will handle anything ham QRO. These are new, currentLy
manufactured items.
73, an
You should probably look for a double pole, I’ve been told you need to open the
shield as wellI’ve had similar interference on my hi z array. I’ve opted to
go a different route
Sent from my iPad
> On Dec 10, 2019, at 11:30 AM, N4ZR wrote:
>
> Now that I've determined that my transmi
Now that I've determined that my transmitting antenna must be
disconnected, in order for my K9AY loop to work successfully, can anyone
tell me what sort of ratings are required for the relay required to do
this remotely? I'm assuming a vacuum relay, but in looking at the MGS4U
list of availabl
Hi Pete
That is one interesting find. I'm going to have to do some tests and see
if I have the same issue.
My RX antenna and TX antennas are about 2 wavelengths apart and both are
very well choked into a 2x8 switch.
I am going to have to give this some thought.
73, Mike va3mw
On Mon, Dec 9, 2
Thank you to everyone who responded to my query. The transmitting
antenna was indeed coupling both noise and signals into my K9AY loops.
I disconnected it at the feedpoint and the noise level on the RX antenna
dropped 4 S-units! Fooling around today in steady rain (which may
affect the quali
I use a a relay to disconnect to the vertical portion just above the bottom
matching coil, keeping all else connected.
I do not understand why the shield should be disconnected ?
If it carries RF back it could be decoupled by ground rods to shield or
chokes.Bu if he top section is open circui
Thanks to everyone who responded. I'm going to begin by disconnecting
my transmit antenna at the feedpoint, as suggested by W3LPL and others,
to see if it is the presence of the transmitting antenna (an inverted L)
that is the problem. Lots of other things to try, too.
--
73, Pete N4ZR
Chec
I had the same problem with my K9AY loop. Despite being
in a wooded area that seemed to have very damp soil the
earth conductivity was poorer than I had expected.
I added eight short radials under the loops and that made a
huge improvement. I also added some cheap CATV ground
rods to tie the ends
If you open the tx antenna feedline for rx, from my experience, you
need to completely open the entire feedline, namely the coaxial cable
shield as well as the center conductor. coaxial relays that maintain
conductivity of the shield when N.O. won't detune/isolate the tx
antenna. I use a pair of
Mark PA5MW
-Original Message-
From: Topband On Behalf Of N4ZR
Sent: Saturday, December 07, 2019 22:14 PM
To: topband reflector
Subject: Topband: K9ay loop not performing
I just put up a K9AY loop, using the Array Solutions control boxes, and am
pretty disappointed. There is no audible
As others have said, a good *RF* ground is a requirement. Here's a comparison
of modeled elevation patterns for a K9AY loop with a very good (low impedance)
RF ground vs one with a very poor (high impedance) RF ground.
https://i.postimg.cc/N0MqJg0x/image.png
The trick to modeling a good ground
r
Subject: Topband: K9ay loop not performing
I just put up a K9AY loop, using the Array Solutions control boxes, and am
pretty disappointed. There is no audible or visible difference in the noise
level, while the received signal strength is down whenever I A/B it with my
inverted L. There does
- Original Message -
From: "Alan Swinger"
To: "Lloyd - N9LB" , "N4ZR" , "topband
reflector"
Sent: Saturday, December 7, 2019 10:19:51 PM
Subject: Re: Topband: K9ay loop not performing
I also put out radials on my K9AY loop and also did what ON4UN
feedline. It has
worked as advertised for many yrs. If not done, suggest chck it w/ AM bcst
stations for directivity.
73 - Alan K9MBQ
-Original Message-
>From: Lloyd - N9LB
>Sent: Dec 7, 2019 4:26 PM
>To: 'N4ZR' , 'topband reflector'
>Subject: Re: Topband:
: Topband: K9ay loop not performing
I just put up a K9AY loop, using the Array Solutions control boxes, and am
pretty disappointed. There is no audible or visible difference in the noise
level, while the received signal strength is down whenever I A/B it with my
inverted L. There does seem to be a
I just put up a K9AY loop, using the Array Solutions control boxes, and
am pretty disappointed. There is no audible or visible difference in
the noise level, while the received signal strength is down whenever I
A/B it with my inverted L. There does seem to be a little directivity,
but not mu
21 matches
Mail list logo
