You will need two stages to get to 33db gain. A pair of BFU590Gx will get you there. The another BFU590GX as a predriver will do the trick. Beaware that these transistors work at 8v, not 12v.
I would also refer to you EMRFD to understand the technique of cascading amplifies. You have to hit appropriate IMD performance of each stage to keep the total IMD down.
On Wed, Sep 11, 2024, 1:56 AM Ravi Miranda via <ravimiranda=
[email protected]> wrote:
Hi,
I know that I may have been possibly down this route earlier, and I
went through some of the message threads from a while ago, so
apologies to all those who may have seen this query before
Let me start backwards.
I plan to get 20 Watts from the K5BCQ amplifier (20W version). This
uses the RD16HHF1 and I have this module - works. So for an output of
43dbm, and assuming a gain of 16 dbm I get 43-16 = 27dbm.
Now, my exciter the barebone version gives me about 330mV (-5.6dbm) at
the output, so I have a deficit of 27+6 = 33 dbm
I can make up this using a PGA103+ (yes, I've been down this route
before) this home brew module has an input transformer on the input
and the output and produces about 19dbm of gain or about 5Vpp into a
50ohm load.
I require to make up the balance using either a 2N5109 or a 2N3866,
but I'm stuck at a design where I cannot deduce the input transformer
for the 2N3866 or the 2N5109. I've tried the Universal Wideband
Amplifier Universal Wideband RF Amplifier ()
I actually used - UWA 2N5109 Characteristics ()
Alternatively, I have a working (homebrew) OPA2677 design that
produces 5Vpp (18dbm).
Can someone point me to a reliable design that has a 50 ohm
termination both ends and can drive the K5BCQ for a 43dbm output.
Apologies for beating the drums on this one again, I really must get
this out working. :-)
Thanks
M0RVI/Ravi
--
I'm here to add more value to the world than I'm using up.
