Amps
[Top] [All Lists]

Re: [Amps] Alpha vs Henry

To: amps@contesting.com
Subject: Re: [Amps] Alpha vs Henry
From: "Roger (sub1)" <sub1@rogerhalstead.com>
Date: Wed, 06 Apr 2011 18:22:41 -0400
List-post: <amps@contesting.com">mailto:amps@contesting.com>
On 4/6/2011 5:05 PM, Al Kozakiewicz wrote:
> Can anyone tell me how much power an AL-1500 is rated to produce at a 100% 
> duty cycle?
>
> During RTTY contests and outputting about 1000 watts, the tube side of the 
> cabinet gets mighty warm.

It should.  Running 100% duty cycle and 1500 watts out at 60% efficiency 
means you are dissipating 1000 watts.  That is a LOT of heat. The temp 
of the exhaust air depends on how much air (CFM @ however many inches of 
H20) the fan can push.  The 8877 is a relatively small tube for its 
ratings, but it has a fairly efficient radiator.  OTOH that means a 
blower that can produce a fair amount of back pressure is required to 
get full output from the tube.

As a comparison, when I had an all electric house I heated the basement 
and ham shack with 4400 watt space heaters mounted in the walls.  In the 
dead of winter it only took a few minutes to heat the 13 X 21' den to 
about 70 degrees. After that the heater would only kick on a few times 
for only a few minutes per hour. That means your amp running under these 
conditions puts out enough heat to require opening the den door to keep 
a reasonable temp.  IOW you could heat a good sized room with that amp 
on RTTY.

> The power supply side seems cool - but then, that's with the cover on.  I 
> don't know how hot is too hot and it would be useful to know at least how 
> much continuous power the supply is rated for.

If you were running large glass tubes that depend on radiation that 
cabinet would be too hot to touch.

73

Roger (K8RI)

> Tube cooling is probably another issue...
>
> Al
> AB2ZY
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>


_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps

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