PGXL SWR Protect reset?

Tom Porada

My PGXL stopped transmitting due to a sudden high SWR. My drunken long wire SWR varies sometimes when the surround trees get wet.

I understand why the Protect feature shut it off but it is not obvious how to reset the amp after clearing the SWR situation.

All I could find in the manual was that the alarm would be cleared upon releasing PTT. When not transmitting on FT8 the PTT is released but no reset.

Only thing to do was to turn PGXL off, short wait, then back on and all is well.

Is there any way to reset while in Standby mode without shutting amp off?

bahillen

Tom,

The amp often does not required to be powered off. But i have found that happen if I don’t quickly dekey, I have had to turn off the primary power switch.

Now the down side of my wire antenna situation. After freezing rain, snow storms arcing insulators or especially high winds a high SWR condition took out my amplifier devices. It was 18 month since I put my PGXL in service. I filled out a helpdesk ticket, Tim answered ticket same day, ran some test overnight, service responded with RMA and UPS label, on its way 24hours from failure. They replace the finals, updated protection circuit and burn in and complete production test. I had amp back on the air 10 days from failure. Great response. My repair ticket said the protection circuit change improved response time as a benefit.

Regarding wire antennas, I have started working on design improvements to increase the insulators and spacing, taking care not to have sharp wire end at the high impedance ends and reduce wind action on the wire. 1,500 watts created new issues like corona at the wire ends that I never saw at 200 to 500 watts. Finally I have passed on some DX when weather is really bad, took out a magazine or other activity.

I think there are two different modes of high SWR that impact the amp differently. One is high VSWR before keying. The second is being keyed up at full power and the antenna shorting. The latter is the most traumatic I would expect. I have decided if conditions are questionable I crank it down to 400 watts reducing the peak voltage and current on all the impacted components.

73

Bill W9JJB

Tom Porada

Thanks Bill. I've only had the amp for about 2 months or so and am delighted with it. Whatever protection circuitry changes were made to your PGXL are probably already in mine, thankfully!

I run about 500 watts max on FT8 and haven't had the SWR shutdown before on CW or SSB at 1KW or FT8 before. I will have to pay more attention to weather & output power and watch the meters more closely when the SWR is a bit more erratic.

I'm in a FL HOA so the long wire is a real compromise running down a pine tree at the far end for about 30'. I'm sure that's where the problem lies but its that or nothing.

I'd rather have to reset the power switch than lose the PGXL.

bahillen

Tom, I keep an eye on the PA temperature. The amp does not run hot but keeping an eye on it lets you know what to expect on different bands and conditions. The amp is very robust.

I find running MEFFA keeps the amp 15 degrees cooler. It takes more drive to get same power that is normal.

I am also in an HOA and not suppose to have any antennas but slowly have pushed the envelope. I have had to increase the use of ferrites to reduce interference with running higher power. 3 loops through the ferrites makes them 9 time’s more effective.

73

Bill W9JJB

Tom Porada

Bill

I decided to give MEffA a try this morning. Now as we speak. Using FT8 at 500w. Finding that the temp stays around 45-50 where before it was sometimes hitting 60-70 and setting off louder fan speeds.

Also requires about 19w drive w/MEffA where it was about 14w previously.

Looking forward to trying it with CW at 1KW, but that never set off louder fans speeds in contests. Not much key down time overall.

73 Tom

AC9S

Note - the situation with SWR changing on a long wire is where I expect Tuner Genius to interrupt the amp while it, the tuner, is retuning.

Keith - AC9S

Tom Porada

That would be a nice feature.

Tom = W4IEE