[Amps] Getting a blower out of the shack

[Ian White]

>
>I would consider a dryer hose since they come in several sizes and have
>various sheetmetal ends that go to the outside vent. Mine is square.
>
>I see no need for anything high priced since temperature is low as is
the
>air pressure.

The length of ducting will lose blower pressure and decrease the air
flow rate, so your amplifier will not be cooled as well as it is now.
The only question is: how much less?

The biggest risk in this project is to obsess about the wrong details.
The transition adapters will not be a problem. The big, important thing
is the duct size and its effect on pressure drop.
 
To minimize the pressure drop, you need to use the largest possible size
of ducting, and avoid sharp bends and other choke points. Installing a
remote blower is almost exactly like installing a remote low-voltage
power supply - to minimize the pressure drop, you need to use "wiring"
with the largest possible cross-sectional area. A larger size of duct
will be less convenient to install, but it IS important.

The transition adapters for the amplifier and the blower are the easy
part. Don't even think about custom metal fabrication until you have
developed your own working prototypes out of more appropriate materials:
standard ducting parts, cardboard, wood... and of course, large
quantities of duct tape.

Before you attack the house walls, you can test the entire project in
the shack using your prototype transitions and the same length of duct.
First measure the exit air temperature of the existing amplifier under
key-down conditions. Then remove the blower and duct-tape everything
into the proposed new configuration, and repeat the temperature
measurement.


73 from Ian GM3SEK