This is a multi-part message in MIME format.
------=_NextPart_000_0007_01C0A28D.9A1F39C0
Content-Type: text/plain;
charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
Hello OM,
I have build a 50 MHz amplifier with a GI-7b tube. It give about 200 =
watt with 2000 volt. I use two coolers from 12 x 12 cm. The problem is =
that when the power comes up, it goes to about 200 watt, it stay there =
for about two at three seconds, then the power drop down to about 20 =
watt, and then it comes up to about 200 watt again. This cycle happens =
in about 3 seconds. The powersupply, including the heater supply from 12 =
volt is okay, it doesn't drop down. I have the same result with an other =
tube.
Do you know what the cause can be ? Every hint is welcome !
Thanks in advance.
Regards,
Roelof (PE5TS)
E-mail: pe5ts@amsat.org
------=_NextPart_000_0007_01C0A28D.9A1F39C0
Content-Type: text/html;
charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML><HEAD>
<META http-equiv=3DContent-Type content=3D"text/html; =
charset=3Diso-8859-1">
<META content=3D"MSHTML 5.50.4134.100" name=3DGENERATOR>
<STYLE></STYLE>
</HEAD>
<BODY bgColor=3D#ffffff>
<DIV><FONT face=3DArial size=3D2>Hello OM,</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=3DArial size=3D2>I have build a 50 MHz amplifier with a =
GI-7b tube.=20
It give about 200 watt with 2000 volt. I use two coolers from 12 x 12 =
cm. The=20
problem is that when the power comes up, it goes to about 200 watt, it =
stay=20
there for about two at three seconds, then the power drop down to about =
20 watt,=20
and then it comes up to about 200 watt again. This cycle happens in =
about 3=20
seconds. The powersupply, including the heater supply from 12 volt is =
okay, it=20
doesn't drop down. I have the same result with an other =
tube.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=3DArial size=3D2>Do you know what the cause can be ? =
Every hint is=20
welcome !<BR>Thanks in advance.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=3DArial size=3D2>Regards,<BR>Roelof (PE5TS)</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=3DArial size=3D2>E-mail: <A=20
href=3D"mailto:pe5ts@amsat.org";>pe5ts@amsat.org</A></FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=3DArial size=3D2></FONT> </DIV></BODY></HTML>
------=_NextPart_000_0007_01C0A28D.9A1F39C0--
--
FAQ on WWW: http://www.contesting.com/FAQ/amps
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
|