Matching EKL ERF2030 Transistors?? HOW

[Low_Boy]

I was watching a video of how important it is to use a matched set of mosfet transistors in a radio. So I got to thinking what is this guy talking about? How can you match a transistor that when put on a tester like the tester I have Peak atlas DCA55 only shows gate, drain and source. It also shows test voltages. There is no HFE on a mosfet. LOL.

 

[Robb]

Video link - please?

 

[Ranch55]

I have often wondered also.
Best I can determine is going by the "turn-on" voltage as shown by the Atlas tester ....
I have seen that this can be a little different between the same MOSFET's ......

 

[Low_Boy]

Sorta B.S. That is why I did not want to post this.

 

[Ranch55]

Yeah, I have seen that. didn't teach me anything ......

 

[StrangeBrew]

You must not have been paying attention.

 

[Martian]

You use a curve tracer.
Another method is to make a jig to see at what voltage current starts to flow thru the device. This is the cheap and fast method to get an idea.
You need a decent power supply and milliammeter but it will get you in the ballpark.

The little peak boxes will give you an idea how well a device works, the jig is a little better since you can spend the time to work out a Vgs curve, the curve tracer is king.

This is all marketing BS. You won't get more noticeable power.

To add insult to injury if all they do is use one of those peak devices to measure it you may be replacing the existing device with one that is actually LESS linear which is what this is supposedly resolving, which in itself is BS too.

 

[loosecannon]

He knows full well that none of his customers are going to be able to verify his work.

I mean, how would they even do that? send the radio to another tech? he'll just answer, "their bench isn't calibrated like mine is" or something to that end.

are they going to send the radio to a NIST lab? I think we all know how hard the laughter on the other end of that phone call would be.

No. they are going to believe him since they already paid their money.

If you really think about it, ol' hardrive doesn't really have to match any transistors.
he just has to tell people that he did it.

I guess the lesson here is that if you tell people that you are the only standard that matters, you don't have to live up to anyone else's standards.

and before the shills come in and start talking about all the otherworldly performance that they now have after his work that they didn't before...

ANECDOTAL EVIDENCE MEANS JACK SQUAT.
you are either happy with your radio or not, and that is all you really know for sure.
armed with this perspective, it's pretty easy to see that what you pay for at FTCB is a nice little story about your radio that you can then repeat to everyone you talk to.

LC

 

[nomadradio]

The parameter that's being matched is the "Vth", or Turn-on Threshold voltage.

We use a transistor tester sold on Chinabay for around thirty bucks. Got in the habit of taking a batch of new FETs and marking this reading on the back with a sharpie marker. When they are pulled from stock for a repair, you simply match up the markings.

The price has dropped since I last bought these.

https://www.ebay.com/itm/LCR-TC1-Tr...function-TFT/232912601116?hash=item363aac401c

73

 

[Martian]

I never heard of a "calibrated bench"
Is that like, the height/width/depth of the actual table?
Or is it how many atoms per square inch and how those atoms align with the space time continuum?

Fine Tunes doesn't know anything about Metrology.
What he does know is how to separate fools and their money.

 

[nomadradio]

Fine Tunes doesn't know anything about Metrology.
What he does know is how to separate fools and their money

I don't have the patience to watch one of his vids all the way to the end. Life is just too short.

73

 

[Martian]

I don't have the patience to watch one of his vids all the way to the end. Life is just too short.
73

I usually get about 90 seconds in before I my "coarse tune" takes me elsewhere

 

[loosecannon]

if you just click through the video randomly, you basically get to see him tapping on a bunch of things.

he taps on a radio.
then he taps on his scope.
then he taps on the bench.

oh, and the calibrated bench?

he uses tuned lengths of coax in between pieces of test equipment that are already terminated to 50 ohms. i mean, you have to take care of all that reactance that is present on the input jacks of RF test equipment.
pretty sure he's still trying to use the Bird wattmeter manual to prove why it needs to be done LOL.
LC

 

[Handy Andy]

Continuous Clarifier...?
(SIGH)

Ok, so you folks know where I stand...

We are a line - if not the only one - to defend that which can't be twisted, construed, or otherwise Bend, Folded Spindled and Mutilated...

 

[kaos513]

More missinformation on youtube to rob peoples money.