Almost no one has even seen a blowtorch! BTW this is part 2, part 1 needs to be taken into account 🙂
Yup, when you don't undo the previous changes or at least make a good faith effort to even see what is going on. A circuit acts as a whole, putting things together series/parallel with who knows what complementing effects can add up to a tangled mess.
That wouldn't be very entertaining, time is better spent relating "dramatic changes that have no measurable difference".
Bonsai warned us of this re: NXP. Gerhard is a wealth of information on other vendors for the same socket. Unless someone does a 1nV MOSFET there will be some AM band RF FET's around for a while. Though apparently AM does not work in all-electric cars.
On Semi lists theirs as still active, each of these must be evaluated at audio frequencies for noise. http://www.onsemi.com/pub/Collateral/EN4839-D.PDF
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Thanks Scott for the chuckle to start the morning. Many sports events used to be carried by AM radio stations, this is falling out of favor, as the new LED scoreboards emit so much EMI garbage they mask the signals completely in arenas and even some baseball parks. Football stadiums still have areas where the S/N becomes adequate.
In one arena they requested an AM transmitter to replay the radio station announcer's direct feed. I went up to a 25 watt AM transmitter inside the building. The antenna was high center on the catwalk. Effective range 25 feet!
In one arena they requested an AM transmitter to replay the radio station announcer's direct feed. I went up to a 25 watt AM transmitter inside the building. The antenna was high center on the catwalk. Effective range 25 feet!
Hey, I still have a radio with the two civil defence logos on the dial. They were valve radios I suspect the JFET's might not be tested for EMP.
Have you ever heard Horowitz playing The Star Spangled Banner from Yankee Stadium, broadcast over AM radio and recorded on a wire recorder? Brilliant, the man hid an extra set of hands somewhere.
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At the same time the BF861(b-c) branded/graded ones show nothing of the sort. BF861a does however. I only did a cursory look and, well, it's the same DS, not sure what's the binning difference. Who knows.
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Whilst Longwave is almost dead in uk, on MW there are still a number of stations holding out. particularly the live sports channel. I'm not sure what the ref-repeaters you can rent at events in UK uses. <google> 62.5MHz FM</google>.
I was expecting this to happen once NXP sold the business.
This few years marked the slow death of all active devices interesting for discrete audio.
First most of the JFETs especially P-channel, then audio MOSFETs and lateral FETs.
And even some audio BJTs are disappearing, like those from Rohm, Sanken, Toshiba, .....
Before long there will only be devices left for Class D & switching.
Time for investing in life time buys, while you still can.
Patrick
> Unless someone does a 1nV MOSFET there will be some AM band RF FET's around for a while.
They do not necessarily have the same (low) noise spectrum in the audio band.
See e.g. 2SK3557 which is the equivalent to BF862.
Measurements Rate SMT Low-Voltage n-JFETs Under Consistent Conditions
Incidentally our own measurement of the 2SK209 showed that it is much closer to the 2SK170 than Dimitri's results.
Patrick
They do not necessarily have the same (low) noise spectrum in the audio band.
See e.g. 2SK3557 which is the equivalent to BF862.
Measurements Rate SMT Low-Voltage n-JFETs Under Consistent Conditions
Incidentally our own measurement of the 2SK209 showed that it is much closer to the 2SK170 than Dimitri's results.
Patrick
When the terminal strips used for wiring parts under the chassis in vacuum tube equipment were being phased out I did what I though would be a lifetime buy of them. I used them all up and am still here!
My good luck Mouser now sells an imported variant that works well. Others around here have found out how handy they are, so we now have used three to five times what I had though would be my closeout buy. Still using them and expect to for another 40 years!
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