----- Original Message -----
From: "J. Leon Pringle, Jr and Audrey S. Pringle"
<pringle50@comcast.net>
To: <Ku4uk@aol.com>
Sent: Wednesday, June 05, 2002 6:56 PM
Subject: Re: [Amps] SK-500 AIR SOCKET
> Dear OM:
>
> Reference EIMAC Data Sheet on EIMAC 8166/4-1000A Radial Beam Tetrode
> Tube dated 10-30-66, page 3.
> .....
> QUOTE
> "Cooling ---Adequate forced-air cooling must be provided to maintain
> the base seal temperatures below 150 degrees C and the plate seal
> temperature below 200 degrees C. Cooling is simplified by the use
of
> the EIMAC SK-500 Air System Socket, and its SK-506 Air Chimney,
which
> control the flow of air around the tube.
>
> When the EIMAC SK-500 Air System Socket is used, the following flow
> rates apply to sea level operation, with an ambient temperature of
25
> degrees C for the operating conditions described:
>
> At 110 megahertz, with maximum rated plate dissipation, an air flow
> rate of 35 cfm is required. The corresponding pressure drop as
> measured in the socket is 1.9 inches of water column.
>
> At frequencies below 30 megahertz, an air-flow rate of 20 cfm
provides
> adequate cooling. The corresponding pressure drop as measured in
the
> socket is 0.6 inch of water column.
>
> In the event that an Air-System Socket and Air Chimney are not used,
> air must be circulated through the base of the tube and over the
> envelope surface and the plate seal in sufficient quantities to
> maintain the temperatures below the maximum ratings.
Seal-temperature
> ratings may require that cooling air be supplied to the tube if the
> filament is maintained at operating temperature during standby
> periods.
>
> In any questionable situation, the only criteria for correct cooling
> practice is temperature. A convenient medium for measuring tube
> temperatures is a temperature-sensitive paint.
> END QUOTE
>
> For your information EIMAC recommended a EIMAC SK-506 Chimney and a
> Eimac HR-8 Heat Radiating Cap be used in conjunction with the EIMAC
> SK-500 Tube Socket.
>
> Whoever tells you that you need a 100 cfm blower is disputing
EIMAC'S
> Data Sheet referenced above. From my experience as a radio amateur
of
> 56 years and owning a number of 4-1000A's I have not found the
> necessity of having a 100 cfm blower when operating the 4-1000A
within
> the legal power limits authorized by the FCC for Amateur Service,
> however the back pressure requirements are absolutely essential for
> proper cooling.
>
> 73,
> J. Leon Pringle, Jr W 5 N A
> E-MAIL: w5na@megagate.com or pringle50@comcast.net
>
> ----- Original Message -----
> From: <Ku4uk@aol.com>
> To: <amps@contesting.com>
> Sent: Wednesday, June 05, 2002 3:05 PM
> Subject: [Amps] SK-500 AIR SOCKET
>
>
> > Has anyone had trouble cooling 4-1000 with the sk500 socket. Will
I
> have a
> > lot of noise with a 100 cfm blower, that some say I need to cool
> tube?
> > Thanks ku4uk@aol.com
> >
> >
> > --- StripMime Report -- processed MIME parts ---
> > multipart/alternative
> > text/plain (text body -- kept)
> > text/html
> > ---
> > _______________________________________________
> > Amps mailing list
> > Amps@contesting.com
> > http://lists.contesting.com/mailman/listinfo/amps
>
>
>
|