Proximity of HF vertical to my satellite antennas
My neighbor has a HF vertical (10/15/20 meter trap) that is about 30 feet from my 2M/70/cm/23cm satellite antennas.
He currently runs 100W and is planning on going to 200W.
Should I be concerned? Will the RF get into my feed lines and blow up my rig? Or into my antenna rotor cables and fry my controller?
I am still in construction mode for my satellite ground station.
Bob W7OTJ.
No
-----Original Message----- From: "Bob Hammond via AMSAT-BB" [email protected] Sent: Thursday, October 24, 2019 06:11 To: [email protected] Subject: [amsat-bb] Proximity of HF vertical to my satellite antennas
My neighbor has a HF vertical (10/15/20 meter trap) that is about 30 feet from my 2M/70/cm/23cm satellite antennas.
He currently runs 100W and is planning on going to 200W.
Should I be concerned? Will the RF get into my feed lines and blow up my rig? Or into my antenna rotor cables and fry my controller?
I am still in construction mode for my satellite ground station.
Bob W7OTJ. _______________________________________________ Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
Should I be concerned? Will the RF get into my feed lines and blow up my rig? Or into my antenna rotor cables and fry my controller?
He is running low power, and your stuff is pretty far away. I have spent a bunch of time hanging around multi transmitter HF contest sites and have never seen even misbehavior of VHF stuff never-mind damage. Your antennas are pretty small compared to your neighbors wavelengths, so coupling will be minimal, and rotors and controllers are well bypassed as they are designed to operate in high RF environments.
de KM1P Joe
Bob, Some external preamps like to put a couple diodes back to back on the input to prevent blowing out the preamp, they will rectify his signal and create hash, it wont hurt anything but will interfere. You would have to look at the schematic of your rig to see if it has similar front end protection. My HF vertical is 50 feet from my sat antennas and 120 feet from another set of sat antennas and I get into both and create a wideband hash with 100 watts, 500 watts totally wipes out sat reception. I have been running this way for years and have yet to damage a preamp or rig. I have had no issues with rotor cables but I do have some clamp on ferrites on them. YMMV 73 Kevin WA7FWF
On 10/24/2019 06:11, Bob Hammond via AMSAT-BB wrote:
My neighbor has a HF vertical (10/15/20 meter trap) that is about 30 feet from my 2M/70/cm/23cm satellite antennas.
He currently runs 100W and is planning on going to 200W.
Should I be concerned? Will the RF get into my feed lines and blow up my rig? Or into my antenna rotor cables and fry my controller?
I am still in construction mode for my satellite ground station.
Bob W7OTJ. _______________________________________________ Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
Thanks all.
What do you all do for a station ground and lightning protection?
Bob W7OTJ
On Thu, Oct 24, 2019 at 8:00 AM Kevin via AMSAT-BB [email protected] wrote:
Bob, Some external preamps like to put a couple diodes back to back on the input to prevent blowing out the preamp, they will rectify his signal and create hash, it wont hurt anything but will interfere. You would have to look at the schematic of your rig to see if it has similar front end protection. My HF vertical is 50 feet from my sat antennas and 120 feet from another set of sat antennas and I get into both and create a wideband hash with 100 watts, 500 watts totally wipes out sat reception. I have been running this way for years and have yet to damage a preamp or rig. I have had no issues with rotor cables but I do have some clamp on ferrites on them. YMMV 73 Kevin WA7FWF
On 10/24/2019 06:11, Bob Hammond via AMSAT-BB wrote:
My neighbor has a HF vertical (10/15/20 meter trap) that is about 30 feet from my 2M/70/cm/23cm satellite antennas.
He currently runs 100W and is planning on going to 200W.
Should I be concerned? Will the RF get into my feed lines and blow up my rig? Or into my antenna rotor cables and fry my controller?
I am still in construction mode for my satellite ground station.
Bob W7OTJ. _______________________________________________ Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership.
Opinions expressed
are solely those of the author, and do not reflect the official views of
AMSAT-NA.
Not an AMSAT-NA member? Join now to support the amateur satellite
program!
Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
Hi Bob these questions would be better answered at the TowerTalk group at contesting.com. When I build my last house I asked many questions about grounding there. When I was having the house built I actually took into account, from the ground up(pun intended) a grounding system. Lots of good knowledgeable people there...
73 Jeff kb2m
-----Original Message----- From: AMSAT-BB [mailto:[email protected]] On Behalf Of Bob Hammond via AMSAT-BB Sent: Thursday, October 24, 2019 11:26 AM To: Kevin Cc: [email protected] Subject: Re: [amsat-bb] Proximity of HF vertical to my satellite antennas
Thanks all.
What do you all do for a station ground and lightning protection?
Bob W7OTJ
On Thu, Oct 24, 2019 at 8:00 AM Kevin via AMSAT-BB [email protected] wrote:
Bob, Some external preamps like to put a couple diodes back to back on the input to prevent blowing out the preamp, they will rectify his signal and create hash, it wont hurt anything but will interfere. You would have to look at the schematic of your rig to see if it has similar front end protection. My HF vertical is 50 feet from my sat antennas and 120 feet from another set of sat antennas and I get into both and create a wideband hash with 100 watts, 500 watts totally wipes out sat reception. I have been running this way for years and have yet to damage a preamp or rig. I have had no issues with rotor cables but I do have some clamp on ferrites on them. YMMV 73 Kevin WA7FWF
On 10/24/2019 06:11, Bob Hammond via AMSAT-BB wrote:
My neighbor has a HF vertical (10/15/20 meter trap) that is about 30
feet
from my 2M/70/cm/23cm satellite antennas.
He currently runs 100W and is planning on going to 200W.
Should I be concerned? Will the RF get into my feed lines and blow up
my
rig? Or into my antenna rotor cables and fry my controller?
I am still in construction mode for my satellite ground station.
Bob W7OTJ. _______________________________________________ Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership.
Opinions expressed
are solely those of the author, and do not reflect the official views of
AMSAT-NA.
Not an AMSAT-NA member? Join now to support the amateur satellite
program!
Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
_______________________________________________ Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
Bob,
This is a very interesting question. In our VHF contesting mountain top setting we are running stacked beams with 1 KW amps within 100 feet of each other. Sometimes makes for challenges in terms of interference but nothing has gotten blown up.
I would be curious to know what others have found with SDR's for the downlink. They do seems a little more prone to overload problems. We routinely struggle with this on Field Day, especially between the 6m and satellite station. Again nothing gets destroyed but the station to station interference can be quite severe.
John
On Thu, Oct 24, 2019 at 9:14 AM Bob Hammond via AMSAT-BB [email protected] wrote:
My neighbor has a HF vertical (10/15/20 meter trap) that is about 30 feet from my 2M/70/cm/23cm satellite antennas.
He currently runs 100W and is planning on going to 200W.
Should I be concerned? Will the RF get into my feed lines and blow up my rig? Or into my antenna rotor cables and fry my controller?
I am still in construction mode for my satellite ground station.
Bob W7OTJ. _______________________________________________ Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
participants (6)
-
Bob Hammond -
jeff griffin -
jim＠k6ccc.org -
John Kludt -
Joseph B. Fitzgerald -
Kevin