This is a multi-part message in MIME format.
------=_NextPart_000_0021_01BEC6F8.564C90C0
Content-Type: text/plain;
charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
IMHO, the use of mechanical relays for T-R switching modern radios and =
amplifiers
is about 10 years behind the times. The PIN diode T-R switch introduced =
by Heath
for the SB-1000 amp, and later produced by Ameritron as the QSK-5 is =
using old
hardware and technology. Ameritron was challenged by an article in QST =
some years
back to use newly available, much more robust PIN diodes in their =
products. I followed
this up by calling Ameritron and asking if they had plans to modernize =
the QSK-5.
The guy I talked to at the time said Ameritron had no plans to make any =
upgrades in
the unit, which proved to be true, as there have been no changes to this =
date in the QSK-5.
Their only upgrade available is a fan to supposedly increase the power =
handling capability.
In the mid '80's, an outfit called Design Electronics Ohio, out of =
Groveport emerged with
a product called the QSK-1500.( Does anyone know what happened to these =
folks?)
In 1985, a fellow by the name of Phil Pesavento developed the QSK-3000, =
using the
new Macom 4P902-985 PIN diodes. These diodes were apparently very =
robust, as the
technical manual describes that they are installed on the board with =
wrenches! (Has anyone
ever heard of Macom, especially where to purchase these diodes?)
I think what this country needs is an honest 3-5 kw rated, stand-alone =
switch that can be used
with any amplifier. In addition to the RF power handling capability, the =
issue of lightning must
also be addressed. I think Design Electronics was on the right track =
when they disappeared.
If they are no longer in business, or are not interested in producing =
the QSK-3000, perhaps
I need to look into doing it myself!
Can anyone furnish any knowledge of the company and/or experiences with =
the QSK-1500 or
QSK-3000?
(((73)))
Phil, K5PC
=20
------=_NextPart_000_0021_01BEC6F8.564C90C0
Content-Type: text/html;
charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
<!DOCTYPE HTML PUBLIC "-//W3C//DTD W3 HTML//EN">
<HTML>
<HEAD>
<META content=3Dtext/html;charset=3Diso-8859-1 =
http-equiv=3DContent-Type>
<META content=3D'"MSHTML 4.72.3616.1301"' name=3DGENERATOR>
</HEAD>
<BODY bgColor=3D#ffffff>
<DIV><FONT color=3D#000000 size=3D2>IMHO, the use of mechanical relays =
for T-R=20
switching modern radios and amplifiers</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2>is about 10 years behind the times. =
The PIN=20
diode T-R switch introduced by Heath</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2>for the SB-1000 amp, and later =
produced by=20
Ameritron as the QSK-5 is using old</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2>hardware and technology. Ameritron =
was=20
challenged by an article in QST some years</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2>back to use newly available, much =
more robust=20
PIN diodes in their products. I followed</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2>this up by calling Ameritron and =
asking if they=20
had plans to modernize the QSK-5.</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2>The guy I talked to at the time said =
Ameritron=20
had no plans to make any upgrades in</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2>the unit, which proved to be true, =
as there have=20
been no changes to this date in the QSK-5.</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2>Their only upgrade available is a =
fan to=20
supposedly increase the power handling capability.</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2></FONT> </DIV>
<DIV><FONT color=3D#000000 size=3D2>In the mid '80's, an outfit called =
Design=20
Electronics Ohio, out of Groveport emerged with</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2>a product called the QSK-1500.( Does =
anyone know=20
what happened to these folks?)</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2>In 1985, a fellow by the name of =
Phil Pesavento=20
developed the QSK-3000, using the</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2>new Macom 4P902-985 PIN diodes. =
These diodes=20
were apparently very robust, as the</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2>technical manual describes that they =
are=20
installed on the board with wrenches! (Has anyone</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2>ever heard of Macom, especially =
where to=20
purchase these diodes?)</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2></FONT> </DIV>
<DIV><FONT color=3D#000000 size=3D2>I think what this country needs is =
an honest 3-5=20
kw rated, stand-alone switch that can be used</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2>with any amplifier. In addition to =
the RF power=20
handling capability, the issue of lightning must</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2>also be addressed. I think Design =
Electronics=20
was on the right track when they disappeared.</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2>If they are no longer in business, =
or are not=20
interested in producing the QSK-3000, perhaps</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2>I need to look into doing it=20
myself!</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2></FONT> </DIV>
<DIV><FONT color=3D#000000 size=3D2>Can anyone furnish any knowledge of =
the company=20
and/or experiences with the QSK-1500 or</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2>QSK-3000?</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2></FONT> </DIV>
<DIV><FONT color=3D#000000 size=3D2>(((73)))</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2>Phil, K5PC</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2> </FONT></DIV></BODY></HTML>
------=_NextPart_000_0021_01BEC6F8.564C90C0--
--
FAQ on WWW: http://www.contesting.com/ampfaq.html
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
Search: http://www.contesting.com/km9p/search.htm
|