[Amps] 160 meter tuned circuit

[Jan Erik Holm]

If this is a single 4-1000A in GG cathode driven
it does not have 50 ohm input Z, 120 ohm is a
better figure.

73 Jim SM2EKM
---------------------------------------------------

Bill Turner wrote:
> On Tue, 16 Mar 2004 17:52:15 -0600, Larry wrote:
> 
> 
>>Hi guys, I recently recieved a home brew 4-1000a amplifier. Amp is tapped for 160 only and running just 1 tube. High voltage is near 5000. This amp has no tuned input circuit and Im not a very good builder. Does anyone have a schematic or know where I can get a tuned circuit for this one band amp? My Yaesu tunes to abt 1.6 swr on auto tuner and antenna standing wave is less than 1.5.   
> 
> 
> _________________________________________________________
> 
> You can use a simple pi-network on the input.  For a Q of 2 and assuming
> input and output impedances of 50 ohms, the values are 1768 pF for both
> capacitors and 4.42 uH for the coil.
> 
> I would recommend using compression type trimmers for the capacitors,
> since the impedances are rarely ever exactly 50 ohms at each end.  500
> volt rating caps should be fine.
> 
> If you have Excel installed on your computer and you want to experiment
> with different values of R and/or Q, VA3UX has an online calculator
> available at
> 
> http://www.vaxxine.com/phil/PI-LCALCv5.xls
> 
> Click on "Improved Pi Calc's".  You can either run this online or save
> it as a file on your computer to run offline.
> 
> --
> 73, Bill W6WRT
> QSLs via LoTW
>