And provide the ALC voltage. If you don’t use ALC (which I don't) then you
can remove them.
73
Jim W7RY
-----Original Message-----
From: Paul Baldock
Sent: Thursday, July 25, 2013 10:41 AM
To: Ed K0KL ; amps@contesting.com
Subject: Re: [Amps] L4B Caution
I suggest you remove the bleeder resistors. They serve no purpose
other than to speed up the bleed down when you turn the amp off. They
create a lot of unnecessary heat in the supply.
- Paul KW7Y
At 10:32 AM 7/25/2013, Ed K0KL wrote:
I had a bad experience when working on an L4B for a pal. The bleeder
resistor mounting
scheme proved to be a little poor (unusual for Drake). When reinstalled,
one of the resistors
shorted to the mounting screw.
This bleeder is held in place by a screw that goes through the center of
the resistor. Mica slices
insulate the ends (chassis and screw head). Only thing is the resistor
arced through the ceramic
base material. So I used glass tape to insulated the screw on the
reinstalled components. This
provided better spacing to the center of the screw.
Note- I replaced the resistors, having the same thing reoccur. Only with
the use of the tape did
the thing calm down. Ordinary electrical tape won't work as it will melt
caused by the heat of
the resistors.
Anyway, that was some time ago, the amp is going strong. Except for a
rather weak plate
transformer, this puppy will no doubt last several lifetimes.
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