AM Power Amplifier - RF Cafe Forums

RF Cafe Forums closed its virtual doors in late 2012 mainly due to other social media platforms dominating public commenting venues. RF Cafe Forums began sometime around August of 2003 and was quite well-attended for many years. By 2012, Facebook and Twitter were overwhelmingly dominating online personal interaction, and RF Cafe Forums activity dropped off precipitously. Regardless, there are still lots of great posts in the archive that ware worth looking at. Below are the old forum threads, including responses to the original posts. Here is the full original RF Cafe Forums on Archive.org

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SDO

Post subject: AM Power Amplifier Posted: Tue Sep 22, 2009 2:50 am

Captain

Joined: Tue Aug 26, 2008 5:18 am

Posts: 22

Location: UK

Hello all,

I need some help about designig power amplifier for 150kHz-1650kHz appliaction.

Gain requirement is better than 40dB with P1dB above 43dBm. Supply voltage 24V.

It is going to be two stage single ended design. I was thinking about using MW6004N as a driver. I am not sure if MRF281 can be used for this application as well.

Any info about the available devices along with some literature for matching networks will be appreciated.

Regards.

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LM317

Post subject: Re: AM Power AmplifierPosted: Sat Sep 26, 2009 9:53 pm

Captain

Joined: Tue May 20, 2008 8:13 pm

Posts: 5

Looks like the MRF281 is going to be out of production soon, so I wouldn't recommend designing it into a new product. It's advertised for applications with frequencies from 1 to 2.5 GHz, way far away from the AM band. Its s-params only go down to 100 MHz.

https://www.freescale.com/files/rf_if/doc/data_sheet/MRF281.pdf

I can't find any data on an MW6004N. Who makes it?

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SDO

Post subject: Re: AM Power AmplifierPosted: Mon Sep 28, 2009 9:34 am

Captain

Joined: Tue Aug 26, 2008 5:18 am

Posts: 22

Location: UK

Hi,

Thanks for your response. Yes, you're right not to use MRF281. The other device was MW6S004NT1

https://www.freescale.com/webapp/sps/sit ... T1&fsrch=1

Any idea about power device which can deliver 10-20w at 1MHz and 24-28V?

Thanks

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IR

Post subject: Re: AM Power AmplifierPosted: Tue Sep 29, 2009 3:15 pm

Site Admin

Joined: Mon Jun 27, 2005 2:02 pm

Posts: 373

Location: Germany

You may try Polyfet www.polyfet.com

They have line of RF Power Transistors for low frequencies also suitable for AM.

Good luck!

_________________

Best regards,

- IR

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SDO

Post subject: Re: AM Power AmplifierPosted: Wed Sep 30, 2009 3:48 am

Captain

Joined: Tue Aug 26, 2008 5:18 am

Posts: 22

Location: UK

Hi,

Thanks for your reply. Polyfet has got some devices and I have seen some more at semelab as well.

Thanks gain.

Posted  11/12/2012