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Technical Topics => Equipment => Topic started by: digitalmod on February 01, 2018, 1705 UTC

Title: WOw, for those with $$ to burn
Post by: digitalmod on February 01, 2018, 1705 UTC

 ;D Well, guys, I think the idea that FETS are not able to deliver the fire to wire is over. Must be some front line technology here Maties !

1500 watts single ended design, freq from 1.8- way up above . These things could be lethal.

https://www.mouser.com/new/nxp-semiconductors/nxp-mrf1k50-reference-circuit/ :-X

Title: Re: WOw, for those with $$ to burn
Post by: KaySeeks on February 01, 2018, 2148 UTC

Note that this is LDMOS. Since we're talking big money, you might as well throw GaN into the mix (Hi Stretchyman!). The maximum die temperature is the same (225 C for both GaN and this LDMOS transistor) and it appears that the costs of both this transistor and GaN might be in the same ballpark too.

I got a chuckle over NXP making a reference design at 27 MHz for this. I assume it's a benchmark for 2-30 MHz performance, but I still got a kick out of a 1500 W amplifier reference design marked specifically for that frequency. "CQ SKIPLAND, CQ SKIPLAND", as they used to say back in the day.

Title: Re: WOw, for those with $$ to burn
Post by: redhat on February 01, 2018, 2354 UTC

27 MHz is an ISM frequency for induction heating.  I've seen tube based stuff in that neighborhood in gas spectrometers used for materials analysis.

List price is $225 per device, about double what you'd pay for a proper MRF151G with 4-5 times the power.  That's not a bad price point.  I'm not sure if you could get that kind of PEP from the device in linear service due to thermal limitations, but an interesting thought exercise.

+-RH

Title: Re: WOw, for those with $$ to burn
Post by: Stretchyman on February 02, 2018, 1328 UTC

Yawn!

https://www.youtube.com/watch?v=1K8LHVRrESE

This is what you want for an HF (SSB) linear.

ALL somewhat old hat really.

I must say I'm becoming somwhat tired of ALL this, 'Look at what you could build' stuff.

Build it then!

It actually not that easy getting it all stable and reliable and reproducable BTW!

Str

Moan over.......

;)

Title: Re: WOw, for those with $$ to burn
Post by: redhat on February 02, 2018, 2006 UTC

Quote from: Stretchyman on February 02, 2018, 1328 UTC

Yawn!

https://www.youtube.com/watch?v=1K8LHVRrESE

This is what you want for an HF (SSB) linear.

ALL somewhat old hat really.

I must say I'm becoming somwhat tired of ALL this, 'Look at what you could build' stuff.

Build it then!

It actually not that easy getting it all stable and reliable and reproducable BTW!

Str

Moan over.......

;)

+1