Seems the 520N is getting harder to get. My question,there are mods out there to upgrade the Cobra 29 LTD CLASSIC to the 520N. Can I use the 520 in this application?
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IRF 520 VS IRF 520N
- Thread starter Charles Brown
- Start date
The specification sheets do not distinguish between the 520N and the 520. I think they are the same part. The "N" could be a revision of the older style.
ButtFuzz
Anti-BS Advocate ● WO0WOO ● Reverend Doctor
For anyone considering the new "ERF2030+ by EKL/Palomar" as a replacement.
From my experience they require greater "turn-on voltage" or bias voltage than the IRF520, so while it is a pin for pin match.. you may not get acceptable results until you increase the bias voltage..
From my experience they require greater "turn-on voltage" or bias voltage than the IRF520, so while it is a pin for pin match.. you may not get acceptable results until you increase the bias voltage..
The IRF520N is a "more rugged" version of the IRF520, it has higher drain current spec than the IRF520. The IRF520 can be used as a substitute for the IRF520N in the Cobra 29 in this case.
~Cheers~
~Cheers~
Well guys, nobody likes to be wrong, but part of being responsible is "owning up to it" when you make an error.
My measurements have been off by an unknown margin of error, for a little while due to a failing 9 volt battery in my multi-meter...
So please disregard my comment about the bias voltage, I'll post more when I know more about this, and after I have an accurate meter in my hands.
My apologies, and best regards to all.
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The data sheets I found on the 520N indicate that the 520 does 60 watts while the 520N does 48 watts.
You are right about parts having different turn on voltages, even parts having the same numbers on them, which is why you should set mosfet bias by drain current or SA only. Completely ignore the part in service manuals that suggest setting mosfet bias by voltage, it don't work.
Mikes Radio Repair has a video where he sets the bias using a spectrum analyzer for minimum distortion, and although the driver bias was right on 50mA when he measured it, the finals were a little different.
As the saying goes, you gotta f#c& around to find out. Mike found out, and then he let us know. Some people missed it...
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I sure wish Mike would start doing videos again. I got in to the hobby/industry after he had already shut the channel down.
From what I can tell other jeolus techs put down him and and his "test equipment". You know the one that says "if you use an attenuator before your spectrum analizer you are a con artist".
I have test equipment that is not calibrated over 50 Watts. I use a power attenuator and do the math. I guess I am con artist to some.
There is nothing wrong with using a known-value attenuator to lower the power of a measured signal to within the power limitations (and calibrated range) of your test equipment. That guys knows it too, otherwise his would be blown up already. I don't think anyone here thinks you are a con artist lol.
To "con" someone is to swindle them by means of conveying false confidence in ones self such that they believe you possess the skills to do what you say you will, when in fact you dont. Calling others con artists for doing it the right way to simply increase ones own business is the actual con, and anyone with half a brain can see it. Either he is crooked or he just wants people to blow up their SA's...
What I said, was to be taken as cynicism. Mike, is one of the few YouTube techs that was legit. The assclowns that have to be the best at everything and trash talk others, to make themselves appear to better at what they do, to people that don't know better is the problem.
Sorry I misunderstood. I get it, I just avoid that stuff now.
I've tried to watch fine tune cb shop a couple times because his audio is decent, but he acts exactly like he is king of everything he does. I can understand talking crap about another tech who rips people off, but he will say shit like "this is wrong but I'm not showing my competetors how to fix it". Why you got a channel then? Defeats the point, I think. When I hear that, I assume he cannot fix it either and I immediately stop the video. I won't watch hard drive's stuff anymore.
There are real RF engineers out there putting good videos, it's just not always a CB radio. Concepts apply just the same though. All Electronics Channel with Gregory (he has channels in two languages, take "channel" off the name and you get his other one) is a great RF channel. He has been doing some videos on HP test equipment circuits explaining how they work and why they did what they did. Those guys at HP had some brilliant ideas! Their "impedance converter" circuit is slick! There is also The Signal Path, RF Get Down, IMSAI Guy. and many many others worthy of mention, all great channels with none of the BS I hear from the usual suspects like hard drive. Just get your knowledge somewhere else.
Gregory at "all electronics channel" explains the concepts behind stuff in depth too. For example, if you want to learn how non-linearities can cause harmonic distortion, he shows you how to make odd or even harmonics, selectively, with just a pot and a couple diodes. Those few pats don't need to be in a CB radio to understand how that principle can apply to everything in a radio, and he puts it in such a way a newby in the hobby can understand it.