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Resolved - Curious LA-1K Shutdown Problem

Bill Pfost
 

My LA-1K was flawless into my dummy load.? It was flawless into the dummy load attached to the HF-AUTO tuner.? When I connected my non-resonant dipole to the HF-AUTO and tried to operate my LA-1K, something transient kept shutting the LA-1K down.? After much testing with no resolution I called Mark at Palstar and described the issue.? I told him what antenna I used and he immediately asked if I use a surge protection device in the transmission line.?

I had two devices in line - a PolyPhaser device and an AlphaDelta device.? I first removed the AlphaDelta device and there was no change in performance - still no amp operation.? Upon removing the PolyPhaser the amp worked as it should, and the HF-AUTO even tuned the antenna to frequency faster than before.

The surge suppression devices, when used in a higher power line with a non-resonant antenna, can create a transient SWR condition which the LA-1K can detect, thus causing a shutdown.?

The amp works perfectly now.? And I now search for a workable lightning protection solution for my station.
 

Bill,
Currently using Morgan HF arrestors on my two HF antennas (non resonant) and no issues with Palstar amp or tuner. Might be worth a look. Your mileage may vary.?


Brian (W0BSF)
Bill Pfost
 

Which are you using, Brian?? The 3kW version?

Bill Pfost


Sent with Secure Email.

‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐
On Tuesday, May 26, 2020 7:33 PM, <fletchbs@...> wrote:

Bill,
Currently using Morgan HF arrestors on my two HF antennas (non resonant) and no issues with Palstar amp or tuner. Might be worth a look. Your mileage may vary.?


Brian (W0BSF)

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Did you try it with the Alpha Delta alone? ?What happened?

Bill, N3EYF

-------- Original Message --------
Subject: [la1k] Resolved - Curious LA-1K Shutdown Problem
From: "Bill Pfost via " <wpfost@...>
Date: Tue, May 26, 2020 6:48 pm
To: [email protected]

My LA-1K was flawless into my dummy load.? It was flawless into the dummy load attached to the HF-AUTO tuner.? When I connected my non-resonant dipole to the HF-AUTO and tried to operate my LA-1K, something transient kept shutting the LA-1K down.? After much testing with no resolution I called Mark at Palstar and described the issue.? I told him what antenna I used and he immediately asked if I use a surge protection device in the transmission line.?

I had two devices in line - a PolyPhaser device and an AlphaDelta device.? I first removed the AlphaDelta device and there was no change in performance - still no amp operation.? Upon removing the PolyPhaser the amp worked as it should, and the HF-AUTO even tuned the antenna to frequency faster than before.

The surge suppression devices, when used in a higher power line with a non-resonant antenna, can create a transient SWR condition which the LA-1K can detect, thus causing a shutdown.?

The amp works perfectly now.? And I now search for a workable lightning protection solution for my station.

Bill Pfost
 

Not yet.? Tomorrow I will try the AD alone.? I will report results here.

Bill Pfost


Sent with Secure Email.

‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐
On Tuesday, May 26, 2020 7:51 PM, Bill Grover <bgrover@...> wrote:

Did you try it with the Alpha Delta alone? ?What happened?

Bill, N3EYF
-------- Original Message --------
Subject: [la1k] Resolved - Curious LA-1K Shutdown Problem
From: "Bill Pfost via " <wpfost@...>
Date: Tue, May 26, 2020 6:48 pm

My LA-1K was flawless into my dummy load.? It was flawless into the dummy load attached to the HF-AUTO tuner.? When I connected my non-resonant dipole to the HF-AUTO and tried to operate my LA-1K, something transient kept shutting the LA-1K down.? After much testing with no resolution I called Mark at Palstar and described the issue.? I told him what antenna I used and he immediately asked if I use a surge protection device in the transmission line.?

I had two devices in line - a PolyPhaser device and an AlphaDelta device.? I first removed the AlphaDelta device and there was no change in performance - still no amp operation.? Upon removing the PolyPhaser the amp worked as it should, and the HF-AUTO even tuned the antenna to frequency faster than before.

The surge suppression devices, when used in a higher power line with a non-resonant antenna, can create a transient SWR condition which the LA-1K can detect, thus causing a shutdown.?

The amp works perfectly now.? And I now search for a workable lightning protection solution for my station.

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Bill Pfost
 

Further investigation shows that any surge suppressor in the transmission line of my non-resonant antenna is not likely to work.? I am left with the direct grounding of my CWSByteMark 9:1 balun () and simply disconnecting the antenna from my system when not in use.

Disconnection is standard operation where I live in central Florida, even with surge devices installed.? Thunderstorms are intense here and lightning is always a risk.
Chuck Scott
 

Bill:

Things about PolyPhaser (and other) protectors that can be a problem.

* Wrong selection for the frequency and power range

* Damage from previous strikes or event nearby strikes

* Perhaps the most insidious is moisture intrusion from the transmission line around the center pin of a connector.

The last one if fun because it all looks normal until you pull it apart. Many types of transmission lines can cause this, even with foam and solid insulaton. Damage to the line or a bad connection somewhere can result in moisture wicking along a multi-strand center conductor for some distance and then penetrate the connectors. (Green or otherwise discolored center conductors.) The result can be that it's somewhat functional at lower power levels but becomes intermittent at higher power.

Yes, any time there is a higher SWR there's a chance a protector will end up at a point on the line with elevated voltage at some point. Protectors are usually rated at low SWR (PolyPhaser typically 1.1:1) so if it's going to be used on a wide-band antenna with a tuner, the protector needs to be de-rated based on the expected maximum SWR (maximum voltage). If not, it could be triggering at power levels a lot lower than rated power causing the amp to trip. Given that, your PolyPhaser protector may be working normally.

So, when testing a line for possible issues, never assume the protector is good or not firing normally on you.

Chuck

On 5/26/2020 6:48 PM, Bill Pfost via groups.io wrote:
...

I had two devices in line - a PolyPhaser device and an AlphaDelta device.? I first removed the AlphaDelta device and there was no change in performance - still no amp operation.? Upon removing the PolyPhaser the amp worked as it should, and the HF-AUTO even tuned the antenna to frequency faster than before.

The surge suppression devices, when used in a higher power line with a non-resonant antenna, can create a transient SWR condition which the LA-1K can detect, thus causing a shutdown.
Chuck Scott
 

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Bill:

Don't forget to terminate the line with a short to protect the line from being damaged by high voltage during a strike.

Also, if you disconnect a transmission line inside of your house, be sure to throw it out the window and a some distance away from the house!!!

Chuck - N8DNX


On 5/27/2020 12:10 PM, Bill Pfost via groups.io wrote:

Further investigation shows that any surge suppressor in the transmission line of my non-resonant antenna is not likely to work.? I am left with the direct grounding of my CWSByteMark 9:1 balun () and simply disconnecting the antenna from my system when not in use.

Disconnection is standard operation where I live in central Florida, even with surge devices installed.? Thunderstorms are intense here and lightning is always a risk.
_._,_._,_
Bill Pfost
 

I'm considering the use of an Alpha Delta Coax Switch to ground the line when not in use.? That switch may be operated without the gas tube (AD calls it a "pill").? I can test to see if the pill causes problems with my LA-1K.
[email protected]
 

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I use one.? It works fine.?
?

From: Bill Pfost via groups.io
Sent: Thursday, May 28, 2020 7:06 AM
Subject: Re: [la1k] Resolved - Curious LA-1K Shutdown Problem
?
I'm considering the use of an Alpha Delta Coax Switch to ground the line when not in use.? That switch may be operated without the gas tube (AD calls it a "pill").? I can test to see if the pill causes problems with my LA-1K.

Bill Pfost
 

So far, the Alpha Delta Coax Switch works great with the LA-1K.?
 

Including the arrestor I'm assuming.

Bill, N3EYF

-------- Original Message --------
Subject: Re: [la1k] Resolved - Curious LA-1K Shutdown Problem
From: "Bill Pfost via " <wpfost@...>
Date: Thu, May 28, 2020 10:01 pm
To: [email protected]

So far, the Alpha Delta Coax Switch works great with the LA-1K.?

Bill Pfost
 

Yes-the “pill”(as Alpha Delta calls the gas tube arrestor) is installed in the switch.

Bill Pfost



On Thu, May 28, 2020 at 22:37, Bill Grover <bgrover@...> wrote:
Including the arrestor I'm assuming.

Bill, N3EYF
-------- Original Message --------
Subject: Re: [la1k] Resolved - Curious LA-1K Shutdown Problem
From: "Bill Pfost via " <wpfost@...>
Date: Thu, May 28, 2020 10:01 pm
To: [email protected]

So far, the Alpha Delta Coax Switch works great with the LA-1K.?


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Thanks, that makes me feel better about the “pill”s I have.

?

Bill Grover, N3EYF

?

From: [email protected] [mailto:[email protected]] On Behalf Of Bill Pfost via groups.io
Sent: Thursday, May 28, 2020 10:41 PM
To: [email protected]
Subject: Re: [la1k] Resolved - Curious LA-1K Shutdown Problem

?

Yes-the “pill”(as Alpha Delta calls the gas tube arrestor) is installed in the switch.

?

Bill Pfost

?

?

?

On Thu, May 28, 2020 at 22:37, Bill Grover <bgrover@...> wrote:

Including the arrestor I'm assuming.

?

Bill, N3EYF

-------- Original Message --------
Subject: Re: [la1k] Resolved - Curious LA-1K Shutdown Problem
From: "Bill Pfost via " <wpfost@...>
Date: Thu, May 28, 2020 10:01 pm
To: [email protected]

So far, the Alpha Delta Coax Switch works great with the LA-1K.?

?

?
Bill Pfost
 

To summarize results for future reference:

1. A PolyPhaser surge suppressor (Model IS-50UX-C0, 2kW) was determined to be incompatible with my Palstar LA-1K / Palstar HF-AUTO installation likely due to my use of a non-resonant dipole antenna.? The PolyPhaser wants to see a 50 Ohm antenna, and a non-resonant dipole has substantially different impedence values as it is tuned by the HF-AUTO over different frequencies.

2.? My Palstar HF-AUTO apparently did not detect the transients, but the Palstar LA-1K did, and shut down.

3. Removing the PolyPhaser from the transmission line in this installation corrected the operation of the Palstar LA-1K.

4. Installing an Alpha Delta Coax Switch with surge suppression in the transmission line does not appear (at this point) to create transients or affect the Palstar LA-1K or the Palstar HF-Auto tuner. ?
?
 

I have experienced the same problem at my station. 10-160 meter vertical, LMR600 coax, Morgan RF Systems M-300 coaxial arrestor, HF-Auto Tuner, LA-1K Amp. I had the most trouble when operation on 75 meters. High SWR, Overdrive, TX delay. Mark told me to remove the arrestor and so far the problem has not repeated.

Mike
Bill Pfost
 

That was the problem. ?Nice to have a simple fix. ?Changing brands of arrestor may be a solution, too. ?Some appear to me more sensitive than others.

73,

Bill
N4APG?



On Fri, Dec 11, 2020 at 07:41, Michael Mangano <mmang2758@...> wrote:
I have experienced the same problem at my station. 10-160 meter vertical, LMR600 coax, Morgan RF Systems M-300 coaxial arrestor, HF-Auto Tuner, LA-1K Amp. I had the most trouble when operation on 75 meters. High SWR, Overdrive, TX delay. Mark told me to remove the arrestor and so far the problem has not repeated.

Mike


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