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#31
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Frank Gilliland wrote:
And Viagra was designed to be a heart medication. I thought it was for male pattern baldness initially. |
#32
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![]() "Telstar Electronics" wrote in message ups.com... Frank Gilliland wrote: Wrong. The ceramic package isn't hollow; on the contrary, it contacts more of the junction's surface area than the heat sink flange (which, BTW, doesn't make "intimate contact" with any part of the junction because it is insulated from the die by the Be Oxide substrate). If the ceramic cap is tied so well to the heat source internal to the transistor... then why don't you just attach the heat sink to the ceramic caps on your new design?... LOL www.telstar-electronics.com You're a ****ing idiot dickhead. You simply don't have any common sense. |
#33
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"U-Know-Who" wrote:
www.telSLAP-electronics.com You're a ****ing idiot dickhead. You simply don't have any common sense. He gets to post his free google spam sig with every reply tho.. |
#34
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![]() "Telstar Electronics" wrote in message oups.com... Frank Gilliland wrote: Actually, that's not such a bad idea. Computer processors and other chips are encased in ceramic and the heat sinks are typically mounted on top. Having an additional heat sink on the top of the transistor certainly can't hurt. I'll check into this and see if it's do-able. I hate to tell you that processor chips (and some others) are specially designed to attach the sink on the top... the RF transistors we're talking about are not. You really are more of moron than thought. |
#35
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![]() "Steveo" wrote in message ... Frank Gilliland wrote: And Viagra was designed to be a heart medication. I thought it was for male pattern baldness initially. They all fix other two. Even if transplants are in order, the new esteem will find the bills for the other two. |
#36
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![]() "Steveo" wrote in message ... "U-Know-Who" wrote: www.telSLAP-electronics.com You're a ****ing idiot dickhead. You simply don't have any common sense. He gets to post his free google spam sig with every reply tho.. But I still love snipping it in my reply. Of course, he'll make another wise and omnipotent statement he |
#37
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"U-Know-Who" wrote:
"Steveo" wrote in message ... Frank Gilliland wrote: And Viagra was designed to be a heart medication. I thought it was for male pattern baldness initially. They all fix other two. Even if transplants are in order, the new esteem will find the bills for the other two. Or once you start banging again in your old age, we can sell you some heart medicine too. Billionaires. |
#38
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On 26 Sep 2006 16:10:26 -0700, "Telstar Electronics"
wrote in .com: LeIand C. Scot wrote: http://perso.orange.fr/f6itv/p2032001.htm (look at location of diodes in photo at right side) Yes, this method is similar to a few "reference" designs shown in the Motorola RF Data Manual . This is a poor method for two resaons. The first is what I explained before... trying to get two diodes in parallel to turn on together is very difficult... if not impossible on a repeatable basis. In the link above the diodes are not in parallel at all. Look at the schematic. In the link you initially provided they are indeed in parallel, but that doesn't mean they are intended to conduct equal currents. If that were the case then they would have current equalizing resistors in series with each diode. From what I can see in the picture, it's clear that only one diode will be working at any given time: the hot one. And I'm sure that's exactly what was intended. Second, the emitters you are feeding with the DC bias are very low impedance. Very low voltage, too. Some might even call it a "ground potential". The bases, on the other hand...... This creates its own problem when attempting to control the base current. This biasing scheme with temp compensation is a "brute force" method that dissipates large amounts of power... and plain doesn't work well. Apparently it works well enough for a homebrew amp. It's not the first time that circuits shown in a reference manual are not production ready. Hey, look what I found on a quick google search: ================ On 31 Jul 2005 15:58:33 -0700, "Professor" wrote in .com: Frank... I wish I was like you... never wrong... and never had to be corrected. Yes, I already knew that, Brian. I tried to turn you onto the right path years ago when you were hacking basic Motorola AN circuits that were intended to be starting designs for engineers, not finished products to be built by CB ampheads. But you were just too impatient to get your "product" sold and get your share of that illegal market. After damage control backfired in your face (because of your lack of education) you vanished. Now you pop back up to spam the group every time you think you have an improvement. You haven't made very many changes, but look at the ones you -did- make -- all were suggestions that I made when I told you all the reasons your amp sucked. Maybe you learned those things from me or maybe somewhere else, but I was right and you know it...... ================ So contrary to recent opinion polls, it's clear that you -can- learn things. You just can't admit that you learned anything from someone else because that might be bad for business. Motorola also shows a much better method of temp comp bias in that same data manual. It uses an op amp and sink mounted thermistor. I'm also using an "active" approach to the temp comp bias in my amplifier... but a totally different circuit using a bipolar transistor as the sense and gain mechanism. I can hold the 500mA bias to 10% from -30 to +85C. Hey Jan, wanna know why Brian won't cut loose his schematic? Because Brian is a hack and his special bias circuit was most likely ripped from this link, which was posted in this group a couple years ago: http://www.ifwtech.co.uk/g3sek/tr-bias/tr-bias1.htm |
#39
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Frank Gilliland wrote:
Hey Jan, wanna know why Brian won't cut loose his schematic? Because Brian is a hack and his special bias circuit was most likely ripped from this link, which was posted in this group a couple years ago: http://www.ifwtech.co.uk/g3sek/tr-bias/tr-bias1.htm Yes Frank... look for an ally. Lord knows you need one... LOL www.telstar-electronics.com |
#40
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Frank Gilliland wrote:
http://www.ifwtech.co.uk/g3sek/tr-bias/tr-bias1.htm Thanks Frank for posting this link. It supports what I've been saying all along about the plain-old diode method working like crap. So why don't you go ahead and use that method on your new amp... LOL www.telstar-electronics.com |
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