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I saw a Texas Star 667 with a pair of mosfet drivers (irf520 if I recall)and 4 dei 2879s. Why would they use fets over the dei 2290?...it's cheaper...about a dollar for the 2 fets. That's been several months ago so I'm curious what else tx star is putting FET's in. Even before they used mosfets they were still junk.

Don't get me started on the AB crap. The tx star cheerleaders will say the class c box just isn't as clean. I've yet to get one of these guys to put a volt meter on the base of the pills so they can watch that crappy bias circuit fall on its face. They'd rather sit around and think up their own theories vs learning something. Most of us would have enough sense to keep the input and output circuit as far apart as possible. Not texas star. They put the traces side by side. When they break into oscillation the harmonics coming out are insane. This is usually what's causing "my swr is good with the amp off but over 3:1 when I turn on the amp". No one wants to spend $75 on an old oscilloscope to see this....their back on the toilet revising their theory.

There is enough info on this forum to build a good bias circuit for an amp. The circuit I use is a refined version of what's posted here. Put it in one of those class c boxes and you'll have a nice amp. It will require some learning.

Stryker makes decent radios as far as exports go. The problems start when you try to cram a 16 pill into one instead of using an external amp.

<blockquote data-quote="543_Dallas" data-source="post: 507629" data-attributes="member: 21044">I saw a Texas Star 667 with a pair of mosfet drivers (irf520 if I recall)and 4 dei 2879s. Why would they use fets over the dei 2290?...it&#039;s cheaper...about a dollar for the 2 fets. That&#039;s been several months ago so I&#039;m curious what else tx star is putting FET&#039;s in. Even before they used mosfets they were still junk. Don&#039;t get me started on the AB crap. The tx star cheerleaders will say the class c box just isn&#039;t as clean. I&#039;ve yet to get one of these guys to put a volt meter on the base of the pills so they can watch that crappy bias circuit fall on its face. They&#039;d rather sit around and think up their own theories vs learning something.&nbsp; Most of us would have enough sense to keep the input and output circuit as far apart as possible. Not texas star. They put the traces side by side. When they break into oscillation the harmonics coming out are insane. This is usually what&#039;s causing &quot;my swr is good with the amp off but over 3:1 when I turn on the amp&quot;. No one wants to spend $75 on an old oscilloscope to see this....their back on the toilet revising their theory. There is enough info on this forum to build a good bias circuit for an amp. The circuit I use is a refined version of what&#039;s posted here. Put it in one of those class c boxes and you&#039;ll have a nice amp. It will require some learning.Stryker makes decent radios as far as exports go. The problems start when you try to cram a 16 pill into one instead of using an external amp.</blockquote>

[QUOTE="543_Dallas, post: 507629, member: 21044"] I saw a Texas Star 667 with a pair of mosfet drivers (irf520 if I recall)and 4 dei 2879s. Why would they use fets over the dei 2290?...it's cheaper...about a dollar for the 2 fets. That's been several months ago so I'm curious what else tx star is putting FET's in. Even before they used mosfets they were still junk. Don't get me started on the AB crap. The tx star cheerleaders will say the class c box just isn't as clean. I've yet to get one of these guys to put a volt meter on the base of the pills so they can watch that crappy bias circuit fall on its face. They'd rather sit around and think up their own theories vs learning something. Most of us would have enough sense to keep the input and output circuit as far apart as possible. Not texas star. They put the traces side by side. When they break into oscillation the harmonics coming out are insane. This is usually what's causing "my swr is good with the amp off but over 3:1 when I turn on the amp". No one wants to spend $75 on an old oscilloscope to see this....their back on the toilet revising their theory. There is enough info on this forum to build a good bias circuit for an amp. The circuit I use is a refined version of what's posted here. Put it in one of those class c boxes and you'll have a nice amp. It will require some learning. Stryker makes decent radios as far as exports go. The problems start when you try to cram a 16 pill into one instead of using an external amp. [/QUOTE]

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