Amps
[Top] [All Lists]

[AMPS] HARRIS RF-110A INFO AVAIL

To: <amps@contesting.com>
Subject: [AMPS] HARRIS RF-110A INFO AVAIL
From: W0YR@aol.com (W0YR@aol.com)
Date: Tue, 15 Feb 2000 07:44:39 EST
The input of the amp is swamped with a 50 ohm dummy load capable of
dissapating 100 w.  I made up my own using sixty(!) 3,000 ohm  2 watt
resistors in parallel.  It is only the size of a coffee mug and works great.
 I also use a 5 db T pad after the swamping resistor because the amp is so
easy to drive.

The input circuit is simple.   A 1,000 ohm, 2 w. resistor goes to ground
across the input.  The grids are fed directly through a .01 mfd capacitor.
Right at the grids are two 2.2 ohm 1/2 watt resistors in parallel for each
tube.  (Effectively feeding each grid through its own 1.1 ohm  1 watt
resistor.)  Bias is applied at the junction/feedpoint of the resistors.

Operating voltages and currents:

Ep = 2990
Max Ei per tube = 900 ma

I cannot measure the grid current at present but I can tell you that the
overload is not kicking out, so I assume I am not drawing grid current in
the
AB1 setting.


--
FAQ on WWW:               http://www.contesting.com/ampsfaq.html
Submissions:              amps@contesting.com
Administrative requests:  amps-REQUEST@contesting.com
Problems:                 owner-amps@contesting.com
Search:                   http://www.contesting.com/km9p/search.htm


<Prev in Thread] Current Thread [Next in Thread>