Re: Topband: Protecting an Array Solutions K9AY Loop from Transmitted RF

[w5zn]

I use these at W5ZN. They are excellent.

73 Joel W5ZN


On 2019-10-11 10:07, Tim Duffy wrote:

Hello Pete:

This is the RX limiter we use to protect front ends at K3LR.

https://www.dxengineering.com/parts/dxe-rg5000hd

It works very well.

73
Tim K3LR

-Original Message-
From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of N4ZR
Sent: Friday, October 11, 2019 7:50 AM
To: Alan Swinger; topband reflector
Subject: Re: Topband: Protecting an Array Solutions K9AY Loop from
Transmitted RF

Array Solutions no longer handles the K9AY components, which actually
came from K9RU's Wolf RF Systems.  It looks like the ICE limiter is
still out there, and reasonably priced, but I have no idea whether it's
a good design - it's pretty old - or just a pair of diodes back to 
back.


73, Pete N4ZR
Check out the Reverse Beacon Network
at <http://reversebeacon.net>, now
spotting RTTY activity worldwide.
For spots, please use your favorite
"retail" DX cluster.

On 10/10/2019 10:08 PM, Alan Swinger wrote:
I use a Model 197 RF Limiter/Arrestor by Industrial Comms Engineers 
for my K9AY Loop. I think I got it from DX Eng ~ 10 yrs ago, but also 
chk w/ Array Solutions since I think they now handle the K9AY Loop. - 
Alan K9MBQ



-Original Message-

From: N4ZR 
Sent: Oct 10, 2019 9:30 PM
To: topband reflector 
Subject: Topband: Protecting an Array Solutions K9AY Loop from 
Transmitted RF


I'm in the process of building up a K9AY loop, using the Array 
Solutions
boxes, and it occurred to me that I probably need to work out some 
way

to protect the preamp in the shack-end box from transmitted RF,
particularly since the K9AY loop is only about 60 feet from the 
vertical

leg of my inverted L and I'll be running 1500 watts.

I can see maybe cutting off the DC to the preamp, but figure that 
won't
be enough. Alternatively, I can probably work out a way to either 
open

or short the feedline coming into the indoor box where the preamp is.
Any advice as to which would be best (opening or shorting)?  I only 
have

one spare transistor.

Advice much appreciated

--

73, Pete N4ZR
Check out the Reverse Beacon Network
at <http://reversebeacon.net>, now
spotting RTTY activity worldwide.
For spots, please use your favorite
"retail" DX cluster.

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Re: Topband: Protecting an Array Solutions K9AY Loop from Transmitted RF

[fmoeves]

I'm on a small lot way to many antennas here.

I use the  _DXE-RG5000HD and _ _DXE-RG5000HD-PM_.

Works great so far 1500 watts on 10 thru 160.

Receiving antennas Beverage and K9AY Loop.

No testing here installed transmitted power and we are good.

Fred KB4QZH

-From: "K4SAV" 
To: topband@contesting.com
Cc: 
Sent: Friday October 11 2019 10:25:03AM
Subject: Re: Topband: Protecting an Array Solutions K9AY Loop from
Transmitted RF

It's likely you won't need any protection from the transmitter 
 (lightning protection may be another story). To verify this you can 
 either use an oscilloscope on the output of the K9AY or just build a 
 diode / cap detector and use a voltmeter.. Then ramp up the power to 
 see how much voltage is picked up. I was surprised when I did this. 
 None of my receiving antennas picked up enough signal to worry about.

 Check the pickup on all frequencies you operate. The gain of a K9AY
is 
 much higher on higher frequencies even though the pattern is very
poor 
 on higher frequencies. It's likely that on higher frequencies there 
 will be more voltage across the K9AY terminating resistor than at the

 output of the antenna.

 Simulation shows no problem at 60 ft separation on any frequency but 
 check it to be sure.

 If you decide to use a limiter, make sure there are no AM stations
close 
 enough to forward bias the limiter (even by the smallest amount). If 
 that happens all kinds of intermod products will show up on receive.

 Jerry, K4SAV
 _
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Reflector
 

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Re: Topband: Protecting an Array Solutions K9AY Loop from Transmitted RF

[James Wolf]

Another solution is the Mini-Circuits Transceiver protection device RLM-33-2W+. 
  

Jim - KR9U 

-Original Message-
From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Martin 
Kratoska
Sent: Friday, October 11, 2019 9:18 AM
To: topband@contesting.com
Subject: Re: Topband: Protecting an Array Solutions K9AY Loop from Transmitted 
RF

I did quite lot of research about protective limiters. The best solution found 
is to use the special TVS diodes RClamp2502L by Semtech which incorporate surge 
rated, low capacitance steering diodes and a TVS diode in a single package. 
During transient conditions, the steering diodes direct the transient current 
away from the protected input. The internal TVS diode clamps the transient 
voltage to a safe level. The low capacitance array configuration allows the 
user to protect up to two high-speed data lines.

RClamp2502L can be used directly "in-line", no additional components needed. A 
new type of "RX front end saver" with Semtech's RClamp2502L is in preparation.

73,
Martin, OK1RR

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Re: Topband: Protecting an Array Solutions K9AY Loop from Transmitted RF

[James Wolf]

Severe overload problems in the K9AY array from the transmitter will also
cause overheating/burning up the 2 watt terminating resistors in the relay
box at the antenna.  I've seen arrays that are only a few feet from the
transmit wires.

Jim - KR9U

-Original Message-
From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of K4SAV
Sent: Friday, October 11, 2019 10:25 AM
To: topband@contesting.com
Subject: Re: Topband: Protecting an Array Solutions K9AY Loop from
Transmitted RF

It's likely you won't need any protection from the transmitter (lightning
protection may be another story).  To verify this you can either use an
oscilloscope on the output of the K9AY or just build a diode / cap detector
and use a voltmeter..  Then ramp up the power to see how much voltage is
picked up.  I was surprised when I did this.  
None of my receiving antennas picked up enough signal to worry about.

Check the pickup on all frequencies you operate.  The gain of a K9AY is much
higher on higher frequencies even though the pattern is very poor 
on higher frequencies.   It's likely that on higher frequencies there 
will be more voltage across the K9AY terminating resistor than at the output
of the antenna.

Simulation shows no problem at 60 ft separation on any frequency but check
it to be sure.

If you decide to use a limiter, make sure there are no AM stations close
enough to forward bias the limiter (even by the smallest amount).  If that
happens all kinds of intermod products will show up on receive.

Jerry, K4SAV
_
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Re: Topband: Protecting an Array Solutions K9AY Loop from Transmitted RF

[Tim Duffy]

Hello Pete:

This is the RX limiter we use to protect front ends at K3LR. 

https://www.dxengineering.com/parts/dxe-rg5000hd

It works very well.

73
Tim K3LR

-Original Message-
From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of N4ZR
Sent: Friday, October 11, 2019 7:50 AM
To: Alan Swinger; topband reflector
Subject: Re: Topband: Protecting an Array Solutions K9AY Loop from Transmitted 
RF

Array Solutions no longer handles the K9AY components, which actually 
came from K9RU's Wolf RF Systems.  It looks like the ICE limiter is 
still out there, and reasonably priced, but I have no idea whether it's 
a good design - it's pretty old - or just a pair of diodes back to back.

73, Pete N4ZR
Check out the Reverse Beacon Network
at <http://reversebeacon.net>, now
spotting RTTY activity worldwide.
For spots, please use your favorite
"retail" DX cluster.

On 10/10/2019 10:08 PM, Alan Swinger wrote:
> I use a Model 197 RF Limiter/Arrestor by Industrial Comms Engineers for my 
> K9AY Loop. I think I got it from DX Eng ~ 10 yrs ago, but also chk w/ Array 
> Solutions since I think they now handle the K9AY Loop. - Alan K9MBQ
>
>
> -Original Message-
>> From: N4ZR 
>> Sent: Oct 10, 2019 9:30 PM
>> To: topband reflector 
>> Subject: Topband: Protecting an Array Solutions K9AY Loop from Transmitted RF
>>
>> I'm in the process of building up a K9AY loop, using the Array Solutions
>> boxes, and it occurred to me that I probably need to work out some way
>> to protect the preamp in the shack-end box from transmitted RF,
>> particularly since the K9AY loop is only about 60 feet from the vertical
>> leg of my inverted L and I'll be running 1500 watts.
>>
>> I can see maybe cutting off the DC to the preamp, but figure that won't
>> be enough. Alternatively, I can probably work out a way to either open
>> or short the feedline coming into the indoor box where the preamp is.
>> Any advice as to which would be best (opening or shorting)?  I only have
>> one spare transistor.
>>
>> Advice much appreciated
>>
>> -- 
>>
>> 73, Pete N4ZR
>> Check out the Reverse Beacon Network
>> at <http://reversebeacon.net>, now
>> spotting RTTY activity worldwide.
>> For spots, please use your favorite
>> "retail" DX cluster.
>>
>> _
>> Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
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Re: Topband: Protecting an Array Solutions K9AY Loop from Transmitted RF

[K4SAV]

It's likely you won't need any protection from the transmitter 
(lightning protection may be another story).  To verify this you can 
either use an oscilloscope on the output of the K9AY or just build a 
diode / cap detector and use a voltmeter..  Then ramp up the power to 
see how much voltage is picked up.  I was surprised when I did this.  
None of my receiving antennas picked up enough signal to worry about.


Check the pickup on all frequencies you operate.  The gain of a K9AY is 
much higher on higher frequencies even though the pattern is very poor 
on higher frequencies.   It's likely that on higher frequencies there 
will be more voltage across the K9AY terminating resistor than at the 
output of the antenna.


Simulation shows no problem at 60 ft separation on any frequency but 
check it to be sure.


If you decide to use a limiter, make sure there are no AM stations close 
enough to forward bias the limiter (even by the smallest amount).  If 
that happens all kinds of intermod products will show up on receive.


Jerry, K4SAV
_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: Protecting an Array Solutions K9AY Loop from Transmitted RF

[john]

When I owned my P40A station I had a Pennant very close to my 160m TX  
vertical.  A K9AY preamp was at the RX antenna feedpoint with voltage  
fed though the coax. If I recall correctly I only shorted the RX line  
going to the radio during TX and left the preamp running.  Most of my  
operation was low power however I have run legal limit and had no  
issues.  What does the preamp manufacture recommend?


John KK9A


N4ZR wrote:

I'm in the process of building up a K9AY loop, using the Array Solutions
boxes, and it occurred to me that I probably need to work out some way
to protect the preamp in the shack-end box from transmitted RF,
particularly since the K9AY loop is only about 60 feet from the vertical
leg of my inverted L and I'll be running 1500 watts.

I can see maybe cutting off the DC to the preamp, but figure that won't
be enough. Alternatively, I can probably work out a way to either open
or short the feedline coming into the indoor box where the preamp is.
Any advice as to which would be best (opening or shorting)?  I only have
one spare transistor.

Advice much appreciated

--

73, Pete N4ZR
Check out the Reverse Beacon Network
at , now
spotting RTTY activity worldwide.
For spots, please use your favorite
"retail" DX cluster.

_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: Protecting an Array Solutions K9AY Loop from Transmitted RF

[Martin Kratoska]

I did quite lot of research about protective limiters. The best solution 
found is to use the special TVS diodes RClamp2502L by Semtech which 
incorporate surge rated, low capacitance steering diodes and a TVS diode 
in a single package. During transient conditions, the steering diodes 
direct the transient current away from the protected input. The internal 
TVS diode clamps the transient voltage to a safe level. The low 
capacitance array configuration allows the user to protect up to two

high-speed data lines.

RClamp2502L can be used directly "in-line", no additional components 
needed. A new type of "RX front end saver" with Semtech's RClamp2502L is 
in preparation.


73,
Martin, OK1RR

Dne 11. 10. 19 v 13:49 N4ZR napsal(a):
Array Solutions no longer handles the K9AY components, which actually 
came from K9RU's Wolf RF Systems.  It looks like the ICE limiter is 
still out there, and reasonably priced, but I have no idea whether it's 
a good design - it's pretty old - or just a pair of diodes back to back.


73, Pete N4ZR
Check out the Reverse Beacon Network
at <http://reversebeacon.net>, now
spotting RTTY activity worldwide.
For spots, please use your favorite
"retail" DX cluster.

On 10/10/2019 10:08 PM, Alan Swinger wrote:
I use a Model 197 RF Limiter/Arrestor by Industrial Comms Engineers 
for my K9AY Loop. I think I got it from DX Eng ~ 10 yrs ago, but also 
chk w/ Array Solutions since I think they now handle the K9AY Loop. - 
Alan K9MBQ



-Original Message-

From: N4ZR 
Sent: Oct 10, 2019 9:30 PM
To: topband reflector 
Subject: Topband: Protecting an Array Solutions K9AY Loop from 
Transmitted RF


I'm in the process of building up a K9AY loop, using the Array Solutions
boxes, and it occurred to me that I probably need to work out some way
to protect the preamp in the shack-end box from transmitted RF,
particularly since the K9AY loop is only about 60 feet from the vertical
leg of my inverted L and I'll be running 1500 watts.

I can see maybe cutting off the DC to the preamp, but figure that won't
be enough. Alternatively, I can probably work out a way to either open
or short the feedline coming into the indoor box where the preamp is.
Any advice as to which would be best (opening or shorting)?  I only have
one spare transistor.

Advice much appreciated

--

73, Pete N4ZR
Check out the Reverse Beacon Network
at <http://reversebeacon.net>, now
spotting RTTY activity worldwide.
For spots, please use your favorite
"retail" DX cluster.

_
Searchable Archives: http://www.contesting.com/_topband - Topband 
Reflector

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Re: Topband: Protecting an Array Solutions K9AY Loop from Transmitted RF

[N4ZR]

Array Solutions no longer handles the K9AY components, which actually 
came from K9RU's Wolf RF Systems.  It looks like the ICE limiter is 
still out there, and reasonably priced, but I have no idea whether it's 
a good design - it's pretty old - or just a pair of diodes back to back.


73, Pete N4ZR
Check out the Reverse Beacon Network
at <http://reversebeacon.net>, now
spotting RTTY activity worldwide.
For spots, please use your favorite
"retail" DX cluster.

On 10/10/2019 10:08 PM, Alan Swinger wrote:

I use a Model 197 RF Limiter/Arrestor by Industrial Comms Engineers for my K9AY 
Loop. I think I got it from DX Eng ~ 10 yrs ago, but also chk w/ Array 
Solutions since I think they now handle the K9AY Loop. - Alan K9MBQ


-Original Message-

From: N4ZR 
Sent: Oct 10, 2019 9:30 PM
To: topband reflector 
Subject: Topband: Protecting an Array Solutions K9AY Loop from Transmitted RF

I'm in the process of building up a K9AY loop, using the Array Solutions
boxes, and it occurred to me that I probably need to work out some way
to protect the preamp in the shack-end box from transmitted RF,
particularly since the K9AY loop is only about 60 feet from the vertical
leg of my inverted L and I'll be running 1500 watts.

I can see maybe cutting off the DC to the preamp, but figure that won't
be enough. Alternatively, I can probably work out a way to either open
or short the feedline coming into the indoor box where the preamp is.
Any advice as to which would be best (opening or shorting)?  I only have
one spare transistor.

Advice much appreciated

--

73, Pete N4ZR
Check out the Reverse Beacon Network
at <http://reversebeacon.net>, now
spotting RTTY activity worldwide.
For spots, please use your favorite
"retail" DX cluster.

_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

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Re: Topband: Protecting an Array Solutions K9AY Loop from Transmitted RF

[Alan Swinger]

I use a Model 197 RF Limiter/Arrestor by Industrial Comms Engineers for my K9AY 
Loop. I think I got it from DX Eng ~ 10 yrs ago, but also chk w/ Array 
Solutions since I think they now handle the K9AY Loop. - Alan K9MBQ


-Original Message-
>From: N4ZR 
>Sent: Oct 10, 2019 9:30 PM
>To: topband reflector 
>Subject: Topband: Protecting an Array Solutions K9AY Loop from Transmitted RF
>
>I'm in the process of building up a K9AY loop, using the Array Solutions 
>boxes, and it occurred to me that I probably need to work out some way 
>to protect the preamp in the shack-end box from transmitted RF, 
>particularly since the K9AY loop is only about 60 feet from the vertical 
>leg of my inverted L and I'll be running 1500 watts.
>
>I can see maybe cutting off the DC to the preamp, but figure that won't 
>be enough. Alternatively, I can probably work out a way to either open 
>or short the feedline coming into the indoor box where the preamp is.  
>Any advice as to which would be best (opening or shorting)?  I only have 
>one spare transistor.
>
>Advice much appreciated
>
>-- 
>
>73, Pete N4ZR
>Check out the Reverse Beacon Network
>at <http://reversebeacon.net>, now
>spotting RTTY activity worldwide.
>For spots, please use your favorite
>"retail" DX cluster.
>
>_
>Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
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Topband: Protecting an Array Solutions K9AY Loop from Transmitted RF

[N4ZR]

I'm in the process of building up a K9AY loop, using the Array Solutions 
boxes, and it occurred to me that I probably need to work out some way 
to protect the preamp in the shack-end box from transmitted RF, 
particularly since the K9AY loop is only about 60 feet from the vertical 
leg of my inverted L and I'll be running 1500 watts.


I can see maybe cutting off the DC to the preamp, but figure that won't 
be enough. Alternatively, I can probably work out a way to either open 
or short the feedline coming into the indoor box where the preamp is.  
Any advice as to which would be best (opening or shorting)?  I only have 
one spare transistor.


Advice much appreciated

--

73, Pete N4ZR
Check out the Reverse Beacon Network
at , now
spotting RTTY activity worldwide.
For spots, please use your favorite
"retail" DX cluster.

_
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