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The Jackson is not a good AM radio and does this. I have many other radios that do not do this at this same dead key on this amp. Your particular radio and amp combination should be looked at by a technician that knows what he's doing to figure out what is going on with your system. Every system has it's own issues.

No it's not. It has to do with the AM circuit in the Jackson. With the same dead key out of my pluto the amp swings forward very nicely. This isn't about why the back swing is occurring, it's about what to look for if you don't have a meter that will show you that it's happening using your SWR meter.

O Lord

I will have to look into that once I get everything setup and my new place.

I do not, but it's not that difficult. All elements are factors of 5, 10 and 25. 25 uses the top scale, 5 the middle and 10 the bottom. You just multiply by the factor on your element to get your output based on with element you are using.

It has to do with the AM circuit in the Jackson. With the same dead key out of my pluto the amp swings forward very nicely. This isn't about why the back swing is occurring, it's about what to look for if you don't have a meter that will show you that it's happening using your SWR meter.

Is this safe? If not how do I correct it?

The Jackson is not a good AM radio and does this. I have many other radios that do not do this at this same dead key on this amp. Your particular radio and amp combination should be looked at by a technician that knows what he's doing to figure out what is going on with your system. Every system has it's own issues. It's not even close to being overdriven. It's just the characteristics of the AM circuit in the radio.

No, it's the AM circuit in the Jackson.

​@@321CatboxWA it does not mean anything. Exactly what I said above... it does not matter what the swr does when you add modulation. Swr should only be checked with an un-modulated carrier. Depending on the design of the radio (and amp), average power can increase or decrease and still have clean modulation/audio. Having the average power decrease and your power supply draw less power accordingly, does not mean anything is wrong, or good, or bad. Some radios actually do have negative average power (backwards swing as some would call it) when modulated, it does not mean anything is wrong. Also note, If you average power increases or decreases when modulation is applied, your swr will most likely increase and decrease accordingly. Extreme PEP and asymmetrical modulation will also affect your swr reading. So I repeat, SWR should only be checked and or payed attention to with just a carrier. Also, I would like to mention that some power supplies are affected by stray RF. I have a Pyramid power supply similar to the one used in this video and simply put, sometimes it works great even when testing something with 200 watts, and other times just a 4 watt radio with dirty output will cause it to complain, sometimes it will just go into protection, sometimes it will drop power, etc... That is why I use deep cycle batteries to test equipment, not power supplies. If you understand what can cause forward swing when using an average reading power meter (not pep), then you can also understand what would cause backwards swing on an average reading meter. Both of those situations (forward or reverse average swing) could have a perfectly clear audio and rf signal, and both of those situations could also have a horrible audio or rf signal. Just looking at meter without using a scope is meaningless. Don't get me wrong, if you have a stock radio that is working properly, most decent techs can make some adjustments using just meters to "tune up" the radio and get a little better audio and or power out of it because they have already done it many times using a scope and have a good understanding of what adjustments "do what" and how far and how much is too much. I hope this helps

This isn't about checking SWR or why its back swinging. It has to do with the AM circuit in the Jackson. With the same dead key out of my pluto the amp swings forward very nicely. It's about what to look for if you don't have a meter that will show you that it's happening using your SWR meter.

@@randybehrmann5454 Ok, but still, why does it matter if "it's happening" ?? That's just how some radios modulate. But still in another comment you say "but if the average is backing up, things are not right" What is not right??

In the radio? That's just how Jackson's are on AM. I have another video using a different radio showing forward swing. This isn't about what the radio is doing, it's about what to look for when this happens. I know why this happened.

@@randybehrmann5454 can you please explain to me why this happens. I see it sometimes on my radios in different situations. I think it might be mirroring the rms modulation swing. Sometimes it swings forward in swr mode too when talking. Thanks

This is not about the radio. I know exactly why this happened, and it has nothing to do with the dead key. I have another video using a different radio showing good forward swing. Jackson's are not good on AM and that's why this happened.

Not really. I show what's going on and explain it clearly. The SWR meter is a good indicator to what is happening with your system, you just have to know what to look for.

Forgive me then ......

Over 10 years ago I tested an antenna on a 25' length of rg8x and it showed swr of 1.5. I had an swr meter on both ends of the coax. They both read 1.5. I cut the coax one foot at a time until I was down to 8 feet left. The swr never changed even a little. I call bullshit and have been using whatever length of coax I want ever since. What a waste of good coax!

I have another video with this same amp and a different radio where everything is going forward. This was simply to show what you could expect with output and amp draw with a backward swing of SWR. This particular radio (president jackson) is not really good in AM, and had very minimal average movement without the amp on. But with the amp on it produces this backward swing.

just wait and see

It's not. This has to do with the AM circuit in the radio causing this. I am not trying to figure out the problem here, just what to look for if you see this happening with your meter.