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Further to this, ? I have also tried sending CW out on 10m via my 3 element beam. CW is totally fine until I move down to 28.002 Mhz or lower. Then it does the same bypass as it does on the entire CW portion of 17m ? Its totally fine everywhere else on the 10m band. ? Anyone else having this issue??? ? Is this a programming thing in the amp to have it cut out near the 10m band edge so CBers don’t use this amp? And if so, maybe the programming thing is doing the same thing on the 17m CW portion for me. ? Just shooting in the dark as my background is computer science, not electronics. ? ? ?
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From: [email protected] [mailto:[email protected]] On Behalf Of Barry via groups.io
Sent: August 8, 2020 3:42 PM
To: [email protected]
Subject: Re: [la1k] SWR High SSB ONLY - When Using LA-1K Amp? Thank you for reply. ? I think your correct. ? Im going to investigate my 17m antenna further. ? 73 ? ? The swaying is not a major issue except in high wind gusts. ? I’m leaning toward the belief that the LA-1K is susceptible to momentary SWR spikes that happen so fast they can only be detected (in my shack, anyway) by viewing videos of the LA-1K’s display on a frame-by-frame basis. ?I have a capture that shows this happening at the same moment the HF-AUTO is displaying a steady 1.04 SWR. ?If the cause is CMC I would think it would be detected by the HF-AUTO before the LA-1K. ?It occurs most frequently at 1000 watts; less frequently at 500 watts; and seldom if ever at 100 watts. ?FW is 1.07B. ?Antenna is an OCFD with numerous chokes on feed-line and interconnecting cables. Your statement that “I? am only having it go into bypass mode now on 17m CW” implies it previously went into bypass mode on other than 17m CW. ?That’s why I was asking in order to have more information before answering.?
On Aug 8, 2020, at 9:56 AM, Barry <barplo@...> wrote:
Kent,? All i was asking is if you resolved your tree swaying issue. Your now asking me a question in reply and expect an answer?
How does that work? ? ? On Aug 7, 2020, at 1:45 PM, Barry via <barplo@...> wrote: ?Kent,
Did you resolve the swaying? tree problem?
I? am only having it go into bypass mode now on 17m CW. 17m Digital is fine. 17m? SSB is fine. What would cause it to only go? ?into bypass mode on? CW, 17m only?
Barry
VE6UM
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I am also having the? Bypass SWR issue? My situation is similar to most of the post I have read. Everything seems to be fine with the amp when running FT8, 200-300 watts output, but on SSB it trips almost immediately when I transmit, even though the SWR is never above 1.4. I am using a Flex 6400M, FTDI cable to the amp (Direct Mode), 160 meter loop and a MFJ 998RT auto tuner. I use the loop and LA-1K on a few other bands with no problems in FT8 mode. I also have a 75 meter dipole that the LA-1K works with on SSB perfectly, no SWR trips. This would suggest there is a problem with the auto? tuner or the loop. However the Flex works fine with the MFJ and loop on? all bands used and the SWR does not vary at all. LA-1K FW is 1.07E
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Beware of arcing on the SSB peaks!? Lightning arrestors, connectors, tuner, antenna high voltage points.? Make sure your RF path will sustain CW power equal to the SSB peak power.? If not clear the arc or back off the power.
de KT3V/Don
On Thu, Oct 15, 2020 at 4:49 PM < w8tz75@...> wrote: I am also having the? Bypass SWR issue? My situation is similar to most of the post I have read. Everything seems to be fine with the amp when running FT8, 200-300 watts output, but on SSB it trips almost immediately when I transmit, even though the SWR is never above 1.4. I am using a Flex 6400M, FTDI cable to the amp (Direct Mode), 160 meter loop and a MFJ 998RT auto tuner. I use the loop and LA-1K on a few other bands with no problems in FT8 mode. I also have a 75 meter dipole that the LA-1K works with on SSB perfectly, no SWR trips. This would suggest there is a problem with the auto? tuner or the loop. However the Flex works fine with the MFJ and loop on? all bands used and the SWR does not vary at all. LA-1K FW is 1.07E
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On Fri, Oct 16, 2020 at 06:14 PM, Don Opdycke (KT3V) wrote:
Don, thanks for the reply. I did find after double checking a loose PL259 but I was still having the SWR Bypass issue. I had already removed the lightning arrestor plug in my Alpha Delta switch with no change in the problem. Since I had some spare time yesterday I decided to move the antenna tuner. I had it mounted inside the house within 15 feet or so of the amplifier. I moved it to a shed outside where the loop center support is located. SWR Bypass problem solved, for now anyway. The amp is working great on ssb and FT8 on all bands now. The MFJ 998RT isn't the best tuner but at least it can be used remotely.
????? Ross, W8TZ
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I am having a problem on 17m also.? Have Palstar HF autotuner and it shows SWR of 1.02 and La1k shows the same when I transmit in Standby at 5 watts.? However when I let the button go SWR on LA1K shows SWR of 3.3 and goes into BYPASS SWR.? ?Maybe some capacitance? somewhere kicking back..? I really wish I had not purchased it (La1K).? Autotuner is very good..? Had LA1K failures on some bands early on so now mainly used on 30? 40 and? 80. Asked Palstar for a price on a replacement board but they did not oblige.? ..It is my costliest mistake in the hobby over approx. 30 years.
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Have you verified all of your coax connections to be acceptable? ?What antenna are you using? ?I am not an expert, but I have had great luck with my LA-1K.
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I'm going to agree, I've used the LA-1K from 10M-160M without
issue from the Amp (Non Amp issue stated below).? What is being
described is a possible feedline and or antenna issue.? My Elmer
also had a similar problem when power was applied, from his LA-1K,
and SWR went crazy. It ended up being the coax between the tuner
and amplifier that caused the issue.
My antenna is way short of 160Meters long, but use a wide range
ATU, and it acts the same way as you described, but it is my
antenna and not the amplifier. My work around is to use FT8
or CW to tune a specific frequency using 100Watts first, and then
introduce the amplifier at the lowest possible power, and stop
transmitting. Adjust C or L depending, and key up again and look
at the values until I get the SWR down to an acceptable level.?
Save those values in the ATU or write them down.
If not convinced it is not an AMP issue, then make or purchase an
antenna for that particular band, and see if the problem persists.
Best Regards,
On 1/25/2023 1:28 PM, Richard Osborne
wrote:
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Have you verified all of your coax connections to be acceptable?
?What antenna are you using? ?I am not an expert, but I have had
great luck with my LA-1K.
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Tune up with 100 watts into the HF Auto then turn power down and turn on the amp. Sometimes 5 watts is not enough. Then when turned the tuner will follow. IMHO the LA1k was your best choice and you just need to have the correct antenna to handle the power.
Perhaps you have a balun that is getting saturated. In any case it is an antenna issue most likely.
S
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I am having a problem on 17m also.? Have Palstar HF autotuner and it shows SWR of 1.02 and La1k shows the same when I transmit in Standby at 5 watts.? However when I let the button go SWR on LA1K shows SWR of 3.3 and goes into BYPASS SWR.? ?Maybe some
capacitance? somewhere kicking back..? I really wish I had not purchased it (La1K).? Autotuner is very good..? Had LA1K failures on some bands early on so now mainly used on 30? 40 and? 80. Asked Palstar for a price on a replacement board but they did not
oblige.? ..It is my costliest mistake in the hobby over approx. 30 years.
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High output power will find the weaknesses in the system if there are any.
On Wed, Jan 25, 2023 at 3:55 PM Steve Snyder < w7cm@...> wrote:
Tune up with 100 watts into the HF Auto then turn power down and turn on the amp. Sometimes 5 watts is not enough. Then when turned the tuner will follow. IMHO the LA1k was your best choice and you just need to have the correct antenna to handle the power.
Perhaps you have a balun that is getting saturated. In any case it is an antenna issue most likely.
S
I am having a problem on 17m also.? Have Palstar HF autotuner and it shows SWR of 1.02 and La1k shows the same when I transmit in Standby at 5 watts.? However when I let the button go SWR on LA1K shows SWR of 3.3 and goes into BYPASS SWR.? ?Maybe some
capacitance? somewhere kicking back..? I really wish I had not purchased it (La1K).? Autotuner is very good..? Had LA1K failures on some bands early on so now mainly used on 30? 40 and? 80. Asked Palstar for a price on a replacement board but they did not
oblige.? ..It is my costliest mistake in the hobby over approx. 30 years.
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I bought my LA-1K four years ago from the original owner.? I use it with a MFJ-998 KW tuner and haven't had any issues.? I know many are now using end fed antennas and experience problems from RF in the shack.? The SWR going up when switching to high power sounds like something breaking down when stressed.??
73,
Allen, W9DZ
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Don’t be discouraged. I felt same way at first and I resoldered ALL my connectors and there were a lot. No issues since. Also ensure all your antennas are working properly and no shorts. Amp has Been solid since. I do occassionaly get the 3.3 SWR during a contest. Not sure why but 99% runs solid. It’s a great amp and needs a solid station (eg: connections, cable, ant, etc.) ? GL Barry VE6UM ?
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From: [email protected] <[email protected]> On Behalf Of David & Hilary Ambler via groups.io
Sent: January 22, 2023 7:04 PM
To: [email protected]
Subject: Re: [la1k] SWR High SSB ONLY - When Using LA-1K Amp? I am having a problem on 17m also.? Have Palstar HF autotuner and it shows SWR of 1.02 and La1k shows the same when I transmit in Standby at 5 watts.? However when I let the button go SWR on LA1K shows SWR of 3.3 and goes into BYPASS SWR.? ?Maybe some capacitance? somewhere kicking back..? I really wish I had not purchased it (La1K).? Autotuner is very good..? Had LA1K failures on some bands early on so now mainly used on 30? 40 and? 80. Asked Palstar for a price on a replacement board but they did not oblige.? ..It is my costliest mistake in the hobby over approx. 30 years.
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My La1k will be 3 years old this July. I bought it new. I use it
with my HF auto and have zero problems.
On 1/26/2023 12:05 PM, Allen Jones via
groups.io wrote:
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I bought my LA-1K four years
ago from the original owner.? I use it with a MFJ-998 KW tuner
and haven't had any issues.? I know many are now using end fed
antennas and experience problems from RF in the shack.? The
SWR going up when switching to high power sounds like
something breaking down when stressed.??
73,
Allen, W9DZ
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I have two LA-1K amps and two HF-AUTO tuners.
One pair is connected to my Flex6400 and the other pair is connected to my IC-7610
The pair connected to my Flex6400, I have no problems, full 1200 watts out on SSB, CW and RTTY
The pair connected to my IC-7610, the LA-1K keeps tripping out on SSB only if I run it over 500 watts. On CW and RTTY, solid 1200 watts.
I tested both set ups on all antennas, Dipole, Yagi, Vertical. No difference.
NE7X...
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My IC-7300 kept overdriving the LA-1K even with relatively low drive (30 watts), no matter what I did. Later, I heard the 7300's are prone to run hot and my 7300 seemed to be one certainly did. But, after I put my Yaesu?FTDX10 in line, the overdrive warnings went away. No problems since. Maybe it's an ICOM issue?? Joe WW8X
I have two LA-1K amps and two HF-AUTO tuners.
One pair is connected to my Flex6400 and the other pair is connected to my IC-7610
The pair connected to my Flex6400, I have no problems, full 1200 watts out on SSB, CW and RTTY
The pair connected to my IC-7610, the LA-1K keeps tripping out on SSB only if I run it over 500 watts. On CW and RTTY, solid 1200 watts.
I tested both set ups on all antennas, Dipole, Yagi, Vertical. No difference.
NE7X...
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It is?an Icom issue unless they've corrected the 7300's overshoot problem.?
73, Kent K9ZTV
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On Feb 1, 2023, at 5:30 PM, Joe Loverti WW8X <jloverti@...> wrote:
My IC-7300 kept overdriving the LA-1K even with relatively low drive (30 watts), no matter what I did. Later, I heard the 7300's are prone to run hot and my 7300 seemed to be one certainly did. But, after I put my Yaesu?FTDX10 in line, the overdrive warnings went away. No problems since. Maybe it's an ICOM issue??
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One needs to look at TX overshoot...
On Wed, Feb 1, 2023 at 4:26 PM Joe Loverti WW8X < jloverti@...> wrote: My IC-7300 kept overdriving the LA-1K even with relatively low drive (30 watts), no matter what I did. Later, I heard the 7300's are prone to run hot and my 7300 seemed to be one certainly did. But, after I put my Yaesu?FTDX10 in line, the overdrive warnings went away. No problems since. Maybe it's an ICOM issue?? Joe WW8X
I have two LA-1K amps and two HF-AUTO tuners.
One pair is connected to my Flex6400 and the other pair is connected to my IC-7610
The pair connected to my Flex6400, I have no problems, full 1200 watts out on SSB, CW and RTTY
The pair connected to my IC-7610, the LA-1K keeps tripping out on SSB only if I run it over 500 watts. On CW and RTTY, solid 1200 watts.
I tested both set ups on all antennas, Dipole, Yagi, Vertical. No difference.
NE7X...
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Mine using the 7610 using 30 to 50 watts on a hex beam or vertical never goes to over drive then tried my 7100 from the mobile rig same results but if i forget and leave it on 100 it does. If If you ever find the problem let me know
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I had the same issue with my IC-7300. The LA-1K would frequently kick out due to overdrive unless I ran the drive super low. Tried 3 different 7300s, same problem with all.? I understand the 7610 does it too.? Poor ALC design on Icom's part.? ?I finally gave up, sold the 7300 and bought a FT-710.? No more problem.
73
Bob? WB8CAC
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The 7300 was/is notorious for
overshoot, unless it's been corrected.?
The overshoot (RF output from the 7300 spiking considerably
higher than the LA-1K likes) causes the LA-1K to protect itself
by kicking to STBY.
73,
Kent
K9ZTV
On 2/13/2023 9:19 AM, Bob WB8CAC wrote:
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I had the same issue with my IC-7300. The LA-1K would frequently
kick out due to overdrive unless I ran the drive super low. Tried
3 different 7300s, same problem with all.? I understand the 7610
does it too.? Poor ALC design on Icom's part.? ?I finally gave up,
sold the 7300 and bought a FT-710.? No more problem.
73
Bob? WB8CAC
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From:?Bob WB8CACDate: Mon, 13 Feb 2023 07:19:12 PSTI had the same issue with my IC-7300. The LA-1K would frequently kick out due to overdrive unless I ran the drive super low. Tried 3 different 7300s, same problem with all.? I understand the 7610 does it too.? Poor ALC design on Icom's part.? ?I finally gave up, sold the 7300 and bought a FT-710.? No more problem.
73
Bob? WB8CAC Different strokes for different folks the saying goes.? I have one of the first 7300's sold in the US.? Bought it from R&L?March, 2016 soon to be 7 years old.? I am the second owner of my LA-1K.? I am a contester, SSB and CW.? Thousands of contacts in 4 years and the only time it goes off line is overdrive (forget to reduce drive power) or high SWR.? Drive power is usually 35 to 40 Watts depending on the band.? I do not have an ALC connection between the radio and the amp.? TX delay is set to 15ms.
I previously had an Acom 1000 and didn't have any issues with it either.
Your MMV.
Allen, W9DZ
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w8tz57
Thomas NE7X
Bob WB8CAC