[Amps] Current draw fan Alpha 77

[Jim Thomson]

Date: Tue, 24 Oct 2017 13:45:19 -0400
From: "Gary Smith" <Gary at ka1j.com>
To: Amps at contesting.com
Subject: Re: [Amps] Current draw fan Alpha 77

<Hi Martin,

They made several of the 77 line and I 
should have been more specific, this is a 
two tube variety. I'm not sure if it came 
originally with two or a 2nd was added 
along the way. It's an amp with a lot of 
overhead available to me as I leave it in 
the CW/Low Volt mode and it loafs along at 
legal limits regardless of what contest 
I'm in.

##  another way around this is to add an extra
relay to the TR setup.   So blower is on full speed
on TX.  On RX, an adjustable 0-3 min  drop out 
delay can be used.   Then you get the max airflow on TX,
and without all the noise on RX.   That concept works for
PTT, VOX ssb,  semi break in Vox cw... or  qsk cw..and any mode. 

##  IE:  max blower rpm on tx.  And reduced blower RPM,  enough
for RX, with idle current cut off.   Hence the adjustable delay to get
from max rpm..down to  a lower rpm.   The T stat solution is probably
more elegant..and simpler to implement. 

Jim   VE7RF