Palstar LA-1K RFI

N3CAL
Posts: 6
Joined: Mon Sep 25, 2017 3:06 am

Palstar LA-1K RFI

Postby N3CAL » Sat May 07, 2022 12:24 pm

I just picked up a Palstar LA-1K Amp and noticed on the waterfall all the noise it generates when powered on. pics are with amp on in standby attached to a dummy load. Anyone else running a LA-1K see this?

LA-1K ON
download/file.php?mode=view&id=2905

LA-1K OFF
download/file.php?mode=view&id=2904

Cal / N3CAL
Attachments
LA-1K ON 1.png
LA-1K ON 1.png (2.21 MiB) Viewed 5175 times
LA-1K OFF.png
LA-1K OFF.png (1.46 MiB) Viewed 5175 times
Last edited by N3CAL on Tue May 31, 2022 2:16 pm, edited 1 time in total.
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w-u-2-o
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Re: Palstar LA-1K RFI

Postby w-u-2-o » Sat May 07, 2022 2:06 pm

Wow! That looks so bad it the amp must be broken somehow :o
alemrush
Posts: 7
Joined: Wed Apr 06, 2022 2:15 pm
Location: Canada

Re: Palstar LA-1K RFI

Postby alemrush » Sat May 07, 2022 3:46 pm

My opinion. Looks like a filtration problem from your dc supply ( 50VDC @42A , switching power supply) .



André

VA2WR
Last edited by alemrush on Tue May 31, 2022 3:52 pm, edited 1 time in total.
André / VA2WR
N3CAL
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Joined: Mon Sep 25, 2017 3:06 am

Re: Palstar LA-1K RFI

Postby N3CAL » Tue May 31, 2022 2:28 pm

I contacted Palstar and they refuse to do anything! They claim those signals are down more than -150db and would be a S1 signal which is no problem! With antenna attached I can hear those peak birdies and it's annoying!

Cal/N3CAL
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w-u-2-o
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Re: Palstar LA-1K RFI

Postby w-u-2-o » Tue May 31, 2022 2:32 pm

Palstar needs to check it's math. The peaks are at -105, which is approx. S4. Those are big signals!
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kc2rgw
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Re: Palstar LA-1K RFI

Postby kc2rgw » Tue May 31, 2022 4:55 pm

That is in NO way normal. I own an LA-1k and it's not even something I've ever noticed. Your amp likely has a broken power supply filter in it.
K9RX
Posts: 414
Joined: Fri Apr 14, 2017 3:47 pm

Re: Palstar LA-1K RFI

Postby K9RX » Wed Jun 01, 2022 12:12 pm

Wow indeed. That is horrendous and (the peaks) would be noticeable on any band except possibly 160M. Totally unacceptable - something wrong with the amp. Palstar needs to step-up and fix it.

Gary
K9RX
WR4N
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Location: Tennessee

Re: Palstar LA-1K RFI

Postby WR4N » Thu Jun 02, 2022 2:14 pm

N3CAL wrote:I just picked up a Palstar LA-1K Amp and noticed on the waterfall all the noise it generates when powered on. pics are with amp on in standby attached to a dummy load. Anyone else running a LA-1K see this?

LA-1K ON
download/file.php?mode=view&id=2905

LA-1K OFF
download/file.php?mode=view&id=2904

Cal / N3CAL


I’m going out on a limb here ... but I’m guessing you bought that used. Correct?
RADIO: ANAN 7000 DLE MK2 (Black Version) Thetis 2.8.11.
PC: HP Desktop - Intel Core i7 (10th Gen) - 16GB memory - 512GB SSD - Intel UHD Graphics 630 - WINDOWS 10 (100% Dedicated to ANAN)
PS: ASTRON 35 AMP (100% Dedicated to ANAN)

Best 73s,
WR4N - David
N3CAL
Posts: 6
Joined: Mon Sep 25, 2017 3:06 am

Re: Palstar LA-1K RFI

Postby N3CAL » Thu Jun 02, 2022 6:03 pm

Hi David, the amp is brand new. I ordered direct from PALSTAR in January and received in late April 2022.

Cal / N3CAL
N3CAL
Posts: 6
Joined: Mon Sep 25, 2017 3:06 am

Re: Palstar LA-1K RFI

Postby N3CAL » Fri Jun 24, 2022 11:43 pm

6/24/22 UPDATE: I shipped amp back to PALSTAR for warranty repair. They confirmed the RFI issue when using the amp on 120 V. (I currently don't have a 240V drop here in the shack so it's 120v only for now). Their fix was adding a ferrite core inside the internal 50V power supply. The internal ferrite fixed the problem! No more RFI! Turnaround was just under 3 weeks. They mentioned they were going to add the ferrite FB77-5621 core to all their production units now. Most of their testing is done on 240v so it wasn't noticed during production. The amp is back in the shack and running great!

Cal/N3CAL
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w-u-2-o
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Re: Palstar LA-1K RFI

Postby w-u-2-o » Sat Jun 25, 2022 12:28 am

Good news!

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