Message	Date	From	Subject
4740	2010-06-02 19:11:41	Robert Cerreto	OOPS!!!! MRF492 Substitute
Sorry guys, Please ignore my last post....sorry, working on two projects at once and had a senior moment.!!!! I really need a MRF492 or suitable substitute to build a 6M 100 watt amplifier. The only one I can find is way beyond my retirement budget. TNKs es 73, Bob WA!FXT [Non-text portions of this message have been removed]
4742	2010-06-02 21:20:19	ajparent1	Re: OOPS!!!! MRF492 Substitute
Unless someone has one laying around to sell cheap RFParts is about it for a reasonable part. MRF492A at about $28 13.8V (officially 70W usually does 100w) MRF140 at about $69 28V 150W The MRF140 is a bit more power at near 150W but you will need 28V for that. The MRF492 is a 12V device that can deliver nominally 100W. I presume you are building the 100w 6M brick QST design. I have a MRF492 amp of that design and MRF140 one spawned off that both being the QST design from years ago. I haven't seen any transistors that are cheaper by any great amount that can do 6M and do it acceptably (passable IMD). Allison

Unless someone has one laying around to sell cheap RFParts is
about it for a reasonable part.

MRF492A at about $28 13.8V (officially 70W usually does 100w)
MRF140 at about $69 28V 150W

The MRF140 is a bit more power at near 150W but you will
need 28V for that. The MRF492 is a 12V device that can
deliver nominally 100W.

I presume you are building the 100w 6M brick QST design.

I have a MRF492 amp of that design and MRF140 one spawned
off that both being the QST design from years ago. I
haven't seen any transistors that are cheaper by any great
amount that can do 6M and do it acceptably (passable IMD).

Allison