[AMPS] ALC from SB-200 reduces FT-900 power on CW

[ohashi@ny.airnet.ne.jp (Kazuo Ohashi)]

Greetings from Japan!!

><w0opw@yahoo.com> writes:
>
>I cranked up my old SB-200 with the Yaesu FT-900 driver 
>and discovered that the FT-900 power was reduced to 50 watts.  This
>was on CW !!.  Removing the ALC line brought the drive power back up
>to 100 watts.

I am using FT-980 & Henry 2KD-5.  I think Yaesu's ALC is sensitive and
shows similar phenomena to W0OPW's.

I added a ZENER DIODE at ALC wire between amp and FT-980 in series.
The polarity is that the anode of ZENER is connected to the amp side.  
The driving power is adjusted by means of change the voltage of
the ZENER DIODE.   In my case, 12V diode gives just 100W driving while
50W if no ZENER DIODE added. 

'73 de JA2DHC/1  Kazuo Ohashi
        QTH: Fujisawa, Kanagawa, Japan
         Homepage: http://www.ny.airnet.ne.jp/ohashi/
          E-Mail: ohashi@ny.airnet.ne.jp


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