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Author Topic: Someone had Corsair II AM TX experience?  (Read 21982 times)

Offline redhat

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Re: Someone had Corsair II AM TX experience?
« Reply #30 on: February 12, 2021, 2142 UTC »
4W is with 14V applied to the PA.  Not really class E, as all I did was put a resonant tank in the drain of the fet tuned to the carrier frequency.  More like class C operation, although I did get north of 80% efficiency out of it.

I'll start a new thread for it when the video is posted.

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Offline Stretchyman

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Re: Someone had Corsair II AM TX experience?
« Reply #31 on: February 12, 2021, 2152 UTC »
Just depends on how you drive it, squarewave = class E, sine =C, sure there's more to it as the o/p has to be bandpass but still the quicker the switching the greater the eff% pure and simples.

Str.
'It's better to give than receive' so why Rx when you can Tx!

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Offline Intruder

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Re: Someone had Corsair II AM TX experience?
« Reply #32 on: February 13, 2021, 1009 UTC »
It's not the best design and have no idea why it gets so much attention.


The reason why it gets some much attention is that many have been built and used in the past. I've found out so much about the designs asking the right people. The parts are easy to get hold of and if your into home construction it can cost under 20 UK pounds to build depending on the version.

I've built Corsette (LM386), Corsair (LM386) and Commando (Transformer) that's on Dave's website and in my opinion they all work well.

Never used these class D ampilifiers but now I've got a few builds under my belt this will be my next project.
« Last Edit: February 13, 2021, 1013 UTC by Intruder »
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Offline Stretchyman

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Re: Someone had Corsair II AM TX experience?
« Reply #33 on: February 13, 2021, 1245 UTC »
So a design that uses less parts (still commonly available) and is more efficient etc gets less attention? Doesn't make sense, apart from the fact it's got some kind of web/utoob kudos. I guess it's the internet generation....

There's so many designs for stuff like this around and 99% would never work without decent layout etc and was the only reason I ever designed a PCB

The class D mod amps are great, bought 100 a few months ago direct. Shame they no longer have the space for the regulator and the front end has a really dumb response, most strange, easily sorted with a few simple component changes.

Details are available..

Str.
'It's better to give than receive' so why Rx when you can Tx!

                                              ;)

Offline Intruder

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Re: Someone had Corsair II AM TX experience?
« Reply #34 on: February 13, 2021, 1541 UTC »
So a design that uses less parts (still commonly available) and is more efficient etc gets less attention? Doesn't make sense, apart from the fact it's got some kind of web/utoob kudos. I guess it's the internet generation....

Str,
I'm not saying it should or will get less attention. For me it was, I've had prebuilt Corsair from Dave back in 2007 and it worked I stupidly sold it. I wanted another one but this time I had to build it, pretty much had all the components for this design in my junk box and yes details of the Corsair are on the net with many people building them and had some excellent support from a HFU member.

Been guided towards the LuLu design by the person that helped me and it will be my next project. If you are willing to provide support I will value you experience and knowledge  :)
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Offline Stretchyman

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Re: Someone had Corsair II AM TX experience?
« Reply #35 on: February 13, 2021, 1751 UTC »
With any decent design using a PCB is by far the best method and sure they used to be expensive but now not so. Shame as I've just given away 20+ LuLu PCBs to a UK chap and don't have any left.

Also the main 'problem' is to how you're going to generate the frequency you want in the first place.

So may I ask, what method do you intend to use?

Str.
'It's better to give than receive' so why Rx when you can Tx!

                                              ;)

Offline Stretchyman

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Re: Someone had Corsair II AM TX experience?
« Reply #36 on: February 13, 2021, 1800 UTC »
Just check "Simplest Tx" post on here.

To modulate just use the class D amps mentioned.

Super simple!

Str.
'It's better to give than receive' so why Rx when you can Tx!

                                              ;)

Offline Charlie_Dont_Surf

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Re: Someone had Corsair II AM TX experience?
« Reply #37 on: February 13, 2021, 2248 UTC »
Just depends on how you drive it, squarewave = class E, sine =C, sure there's more to it as the o/p has to be bandpass but still the quicker the switching the greater the eff% pure and simples.

Str.

Umm yeah, there is more to it.

Like, amplifier class is not defined by how it is driven. It is defined by the shape of  the drain/collector waveforms.

Also sinewave drive can also be Class A or B, in addition to C, it depends upon the associated drain waveform. Squarewave drive can associated with class D,E,F, S or J.
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Offline Charlie_Dont_Surf

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Re: Someone had Corsair II AM TX experience?
« Reply #38 on: February 13, 2021, 2301 UTC »
The reason why it gets some much attention is that many have been built and used in the past. I've found out so much about the designs asking the right people. The parts are easy to get hold of and if your into home construction it can cost under 20 UK pounds to build depending on the version.

I've built Corsette (LM386), Corsair (LM386) and Commando (Transformer) that's on Dave's website and in my opinion they all work well.

Shhh. Quiet. You're destroying Stretchy's bullshit narrative that everyone MUST.THINK.LIKE.HE.DOES and no one could be happy and content without doing what he wants. There's probably been more Corsette, Corsairs (I&II) and Commandos built than he has ever sold and that gets under his skin.
I don't STRETCH the truth.

"Every minute I spend in this room, my signal gets weaker.
Every minute Charlie squats in the bush, his signal gets stronger."

Offline Stretchyman

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Re: Someone had Corsair II AM TX experience?
« Reply #39 on: February 14, 2021, 1154 UTC »
How wrong you are...
'It's better to give than receive' so why Rx when you can Tx!

                                              ;)

Offline Charlie_Dont_Surf

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Re: Someone had Corsair II AM TX experience?
« Reply #40 on: March 15, 2021, 2120 UTC »
How wrong you are...

Well, you do try to lord all over a lot of people here so...
I don't STRETCH the truth.

"Every minute I spend in this room, my signal gets weaker.
Every minute Charlie squats in the bush, his signal gets stronger."

Offline Kingbear Radio

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Re: Someone had Corsair II AM TX experience?
« Reply #41 on: March 20, 2021, 0716 UTC »
This latest exchange is a good reason that all companies should have a public relations department. PR serves up the platitudes, and it's fake sincerity, but those words, saying nothing, seem to soothe people.
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Offline Syck0

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Re: Someone had Corsair II AM TX experience?
« Reply #42 on: January 31, 2023, 0038 UTC »
the LM 386 runs hot because of the 12 volts you need to set up a 8 volt regulator circuit for the LM386

Flying high thru the sky on these electromagnetic waves :)
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Offline Dare4444

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Re: Someone had Corsair II AM TX experience?
« Reply #43 on: February 15, 2023, 1824 UTC »



This is another solution who wish to do it the old fashioned way. It outputs 40mW of carrier with 160mW PEP. It can drive an IRF510 for 1W out with 4W peaks at 100% modulation. Audio sounds great. Remove the mic and feed audio directly to pin 3 of lm386 via 100n capacitor or C8. A variable 10K pot fed by a 10u capacitor can also be added to pin 3 to set the modulation depth.

« Last Edit: February 16, 2023, 0257 UTC by Dare4444 »

Offline Dare4444

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Re: Someone had Corsair II AM TX experience?
« Reply #44 on: February 16, 2023, 1026 UTC »
Add another linear push-pull power amp for 15W carrier and 60W PEP.