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Like Evan, I too have been unable to create a 60V high voltage failure through high SWR, either in LTS simulation with a huge range of loads, or by accidentally transmitting into an open circuit. I

Hello-- Please note that I currently do NOT have a dog in any of the current digital dogfights which are consuming quantities of various MOSFETs used as final amplifiers in QRP equipment. Has anyone

Hi Hans The only load I can think of to cause a BS170 over-volt failure is something hanging off of the antenna connector that will induce a high SWR, like some non-inductive resistors series-ed or

MMBF170 rated 417°C/W (yikes!) vs BS170's 150°C/W makes it a poor substitute, thermally.??https://www.onsemi.com/pdf/datasheet/mmbf170-d.pdf 73, Don N2VGU

John Zbrozek started the development of an LTSpice IV model of the QDX PA that he and I expanded to test a theory on what happens when the transmitter is turned off at the end of an FT8 cycle.? The

As a pilot of over 30 years in small aircraft (mine was C150) the concept of a parachute was reserved for the willful jumping out of an airplane. The risk analysis is that most samll planes are

It's always Blursday! 73, Willie N1JBJ

I'm still thinking squirrel cage blower - with a large Peltier Junction. Lee KX4TT

That and the SOT23 part is? far lower power rating,? 300mW. Data sheet posted to thread: /g/QRPLabs/message/109864 -- Allison ------------------ Post online only, direct email

Hello Jim If > 60V excursions are the usual killer of BS170s, do you have an actual defined load circuit that will by measurement, produce over 60V peaks at the drains of the BS170s? If so I'd love

Hello JimUse to work in a shop about 30 years ago where we crammed 10 pounds of stuff into a 1 ounce bag.This was before surface mount transistors became readily available. Without knowing it we kind

Clive, You're right that the SOT-23 package is probably better thermally than the TO-92. More lead area, less plastic. But you can't socket the SOT-23 and changing them is a PITA for most

Hans (G0UPL), I have been had. My head is hanging low, I have been beat at my own game, but by the master. What year is this anyhow? Last comment on this topic! 73, Billy

Thanks Walt I have corrected the typo on pages 1 and 11. 73 Hans G0UPL http://qrp-labs.com https://www.buymeacoffee.com/g0upl

Jim (N6OTQ), I just checked Amazon and there are several vendors for the BS170. Most offer 10 for less than a dollar. I am willing to spend that kind of money for a joint experiment. What say? 73,

Whoooaaa Billy I had Tuesday off, what, when? What day is it today anyway. Ah Wednesday. Well I guess I did sleep half of yesterday until post-lunchtime, after the good post-doctor visit feeling that

Jim, you need to chase some of the guys dissecting and polishing various old chips. ?My gut feeling with regards to the BS170 saga is that a well soldered joint with good penetration to the topside

Absolutely so. As a further aside, the interesting if slighly simmering discussion around performance of typical amateur homebrew "bog standard" attenuators and dummy loads does leave me pondering

Hans (G0UPL), Strength, Pull it together! As you said, "I'm supposed to be on re-entering rolling ball phase AVOIDANCE." Ok you have had Tuesday off. I guess you deserve a vacation, you have had it.

The smaller Black Plastic kit was indeed ours also. We sold a License on our patent to allow a company called Arrow Handicraft to make them. Many people could not afford the all furniture grade hard