Re: boosting the power on 28 MHz #ubitx

K9HZ <bill@...>

See the posts in the 3/21-3/31 date range (look for “RD16HHF1 power curve flattening”)… We’ve been through this.  There were SPICE simulations, changes to all of the RF stages (bypass caps), including changing out T11 including various tries at compensating for excess inductance at HF with parallel C, different feedback resistors and caps. RD16HHF1 transistors for IFR510’s, PA voltage is 14V.


Sorry for the terse answer, I’m trying to finish a prototype line section before I leave for Dayton.



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From: [] On Behalf Of Jerry Gaffke via Groups.Io
Sent: Saturday, May 12, 2018 10:24 PM
Subject: Re: [BITX20] boosting the power on 28 MHz #ubitx


When you see 26 and 19 Watts, what exactly are you looking at?
What mods, and at what voltage to the drains?


On Sat, May 12, 2018 at 07:59 pm, K9HZ wrote:

I see a maximum of 26 watts on 40 meters and 19 watts on 10 meters...


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