In a message dated 10/15/00 11:38:35 PM Eastern Daylight Time,
cx6vm@adinet.com.uy writes:
>
> HI GUYS:
>
> I HAVE THE POSIBILITY TO BUY AN AMERITRON AL-80A FOR REASONABLE PRICE.
>
> I WANT IT TO HAVE AS A SECOND AMP, FOR BACK UP IN CASE THE MAIN AMP
> FAILURE DURING A CONTEST.
>
> I LOOKED FOR THIS MODEL BUT ONLY FOUND AL-80B, NOT AL-80A, SO I WANT TO
> KNOW IF SOMEONE HAVE ANYTIME THIS AMP OR KNOW ABOUT IT TO GIVE ME SOME
> FEEDBACK.
>
> DO YOU KNOW ABOUT ANY PROBLEM WITH THE MODEL AL-80A????
>
> WILL APRECIATE VERY MUCH YOUR INFO
>
> THANKS IN ADVANCE
>
> JORGE
> CX6VM
>
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Jorge,
A friend of mine owned an AL-80A. He told me that the inductance in both the
anode RF Choke and the filament choke were insufficient. He rewound both of
these adding turns in each instance and more ferrite rod before solving the
problems.
The lack of sufficient inductance in the filament choke caused the tube to
dissipate too much heat in the anode even when at idle.
Apparently the bias voltage was incorrectly dimensioned for proper operation.
The manner in which the unit is wired is poor.
After reworking the amplifier, the output power went up about 30% and ran
much cooler.
Bueno suerte y setenta y tres de
Dave, WT8R
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