[AMRadio] GK500B blower

[Jim Wilhite]

The squirrel cage outlet is pointed down into a hole about 1 sq. in.  There is a plate covering the bottom of the chassis.  As far as I am concerned air flow is barely adequate evidenced by a 50 k ohm resistor that will show heat marks.  

Also the 6 k dropping resistor for the lower stages may change even though it is wire wound.  I found a small 120 V muffin fan that I mounted near the hole to direct air toward the tube base to assist cooling of the bias resistors and tube base pins.

One should be sure the base cover seals well.  I have never seen a 500 with all the screws still in the cover plate.

Jim/W5JO

Rob Atkinson <ranchorobbo at gmail.com> wrote:

>I looked at the photos and it is not clear to me what the blower is
>supposed to cool.
>It looks like it pressurizes the chassis?
>
>Rob
>K5UJ
>
>
>On Sun, Jan 1, 2012 at 6:49 PM, Dan Osborne <wb5afy at wb5afy.net> wrote:
>> OK guys - follow this link to W0YVA's web site for pics of the RF
>> deck with the blower -
>> http://www.isquare.com/personal_pages/globeking500-rfdeck.htm
>>
>> looks to me like the output of the squirrel cage is about 1 inch square..
>>
>> and - yes - my backup plan is to use a muffin fan mounted on top of
>> the RF deck !!
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