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Fact or fiction

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What were you running for an amp Gary? A lot of guys think putting a filter between the exciter and the amp is dumb because the amp will "generate harmonics" however a properly run amp will only amplify what it is driven with and using a filter between the radio and amp allows for a much smaller filter and a clean drive signal. That is my plan when I get the Larcan amp up and running. I have a filter I bought from someone online......a ham......in kit form rated at 300 watts IIRC. Hard to get a good 6m filter rated for 1500 watts.

It’s how I figured best position (glad to have a confirmation).

(What amp used not germane to my thanks.)

.
 
https://www.dunestar.com/product/single-band-bandpass-filters/

He no longer lists one for 11 meters. However, be easy to configure one to work in that range. I have used one of his for 6-meter filters during Field Day. I had it between radio and amplifier, found it to work very well. It performed well at reducing some receiver noise and sending a clean signal to the amplifier. Worked well at rejecting out of band signals and wide range receiver noise.
Seems like a good guy to deal with might contact him about the special build for 11 meters filter.
These are rated at 200 watts PEP SSB...so no high output rigs or Big Swinger AM'ers...He lists the duty cycle of 100 watts PEP for RTTY/Digital signals...so this would include AM also...IMHO
All the Best
Gary

That’d work with three of my four rigs. Thanks.

.
 
No not left, just busy with life...

Back then, a different story...but now is not the time for it...Family issues and marriage take priority.

I remember the last time he left forever.

Funny how Forever, isn't...It's why I am here...still...

{tic...tic...tick ... (no not tap)} Chirp, Chirp - Chirp...of crickets...

Once you review those articles, the WIKI offers some links to externals that are tutorials - but in any case, the articles bring some insight into what AM regulation tends to fall flat when trying to go up past 5.6 volts DC bias - and when you get down to 4.8 volts, the thing swings symmetrically and then lower than that - asymmetrically.

A lot of this has to deal with the drawbacks of symmetry and what it (Radio platform) can reproduce when you have limits on the voltages the circuit uses to generate equal envelope swing above and below.
  • Due to the nature of 4 watts and the FCC PEP requirements - the effort seems to have been made to be intentionally done to limit power swings - but then too - other efforts were added to lessen the end-users ability to rework the sections to attain an audio amp power drive signal to track the power regulation.
  • It's why we have NPC...
It is my thoughts that they knew this can be corrected, they (Read this as Manufacturing and engineering) knew of this so they tried to avoid the elephant in the room and just avoid it altogether, but the 148GTL and Grant XL offer the best "conversion platform" - due to the Audio Chip drives directly.

That's the big clue for people to work with - right there...placed limits on the voltages in key areas....

The voltage is not the problem, you can attain symmetry if driven right and with proper voltages. You lose the forward peaking swings when you go up past 1/2 the supply line. There is your quandary and line drawn in the sand.

So what does the 29 offer that others don't?

Voltage transformation - at the cost of bandwidth - to obtain forward power swing. You compress more, but you also get the voltage boost (Bill Eitner KD6TAS) discussed in CB Tricks days with CB Doctor. That's helps with the Envelope.

The tutorials give you clues as to what to do with the voltage push needed to offset the losses in swing due to audio compression.

Then to re-attain the balance, you need to apply more power in voltage boost (current follows so you'll need a constant current sourcing - read linear or switching - both to buck up the power requirements and handle the current needs they will demand - squared.

So I may have said too much already, but - have fun kids!
 
No not left, just busy with life...

Back then, a different story...but now is not the time for it...Family issues and marriage take priority.



Funny how Forever, isn't...It's why I am here...still...

{tic...tic...tick ... (no not tap)} Chirp, Chirp - Chirp...of crickets...

Once you review those articles, the WIKI offers some links to externals that are tutorials - but in any case, the articles bring some insight into what AM regulation tends to fall flat when trying to go up past 5.6 volts DC bias - and when you get down to 4.8 volts, the thing swings symmetrically and then lower than that - asymmetrically.

A lot of this has to deal with the drawbacks of symmetry and what it (Radio platform) can reproduce when you have limits on the voltages the circuit uses to generate equal envelope swing above and below.
  • Due to the nature of 4 watts and the FCC PEP requirements - the effort seems to have been made to be intentionally done to limit power swings - but then too - other efforts were added to lessen the end-users ability to rework the sections to attain an audio amp power drive signal to track the power regulation.
  • It's why we have NPC...
It is my thoughts that they knew this can be corrected, they (Read this as Manufacturing and engineering) knew of this so they tried to avoid the elephant in the room and just avoid it altogether, but the 148GTL and Grant XL offer the best "conversion platform" - due to the Audio Chip drives directly.

That's the big clue for people to work with - right there...placed limits on the voltages in key areas....

The voltage is not the problem, you can attain symmetry if driven right and with proper voltages. You lose the forward peaking swings when you go up past 1/2 the supply line. There is your quandary and line drawn in the sand.

So what does the 29 offer that others don't?

Voltage transformation - at the cost of bandwidth - to obtain forward power swing. You compress more, but you also get the voltage boost (Bill Eitner KD6TAS) discussed in CB Tricks days with CB Doctor. That's helps with the Envelope.

The tutorials give you clues as to what to do with the voltage push needed to offset the losses in swing due to audio compression.

Then to re-attain the balance, you need to apply more power in voltage boost (current follows so you'll need a constant current sourcing - read linear or switching - both to buck up the power requirements and handle the current needs they will demand - squared.

So I may have said too much already, but - have fun kids!

I'm just poking Andy. Take care of the family and be well.
 
I've had my hands full for a while...

You take care as well!:)


You just keep on keepin’ on, Handy Andy.
It’s a rare gift. (Comes with a price tag).

As I said to you in a PM at my beginning, that gift on display is what made me decide that this forum was worth the time and energy to learn Radio. It wasn’t going to be past me with THAT quality of disquisition.

There are endless enthusiast and tech forums. But too few where the range & depth bring the big fish up from the depths.

WWDX is blessed by many (genuine) men.

Pour fresh coffee.
Crack a pack of smokes.
Release air brakes.

What’s down that road ahead can’t be described by yesterday


 
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