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RM-3 MOSFET TRANSISTOR

TonyV225

W9WDX Amateur Radio Club Member
Apr 18, 2005
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Wisconsin
What do these RM-3 Mos transistors actually put out? I see these being used in different smaller amplifiers and was wondering how much power AM and SSB they will produce and what the drive is they will take??

I see these little RM Italy amplifiers run these and I often wonder if their worth buying them as people do. Will they produce 50 watts even?? Or are they more like a 30 watt transistor?? That would be funny considering a dual final radio will do 30 watts.

I was just looking around on the net and see these little KL-40 and KL-60 amplifiers and nobody really says what the heck they actually do for power. There so damn cheap I cant hardly believe they would do much for output but what do I know Ive never owned one so thats why I am asking who really knows about these transistors?? Curiosity killed the cat kind of thing. ;) :confused:
 

Ive seen claims that RM3 is HUF75345P3, but this is dubious since this fairchild part has gate charge/gate capacitance which is an order of magnitude worse. Not something you want for 27MHz.

More likely its just like ERF-2030: cherry picked IRF520 for highest gain and/or efficiency.
 
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tony,
the last rm3 amp i have had on a watt meter was the kl203, it made 122w fm from 10w drive, thats pushed very hard, 5w drive makes about 100w fm,

id say neither hufs or 520's are rm3's,
rm3's got too expensive to warrant repairing the little rm's so i tried both in rm3 amps even rebiased them,
neither work right.
 
sorry its an old post now only just seen it!! not sure if iam on the right track here but! i thourght they were ms1307!!!!??? the same that was in some of the cte amps!!! ive replaced the rm 3s with these and all seems good!!! not sure if this is any help but thats what i have found anyway 73s.
 
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The "RM3", also known as 2N6045, is a 75 watt/100v NPN power transistor. The mystery behind the RM3 is they use what ever transistors they get their hands on in bulk pricing and cross the factory stand and restamp the transistors, in house, with the RM3 number. Not all RM3 transistors that come from RM Italy are the same, there is about 15 different variations that have been used over the years.
 
i actually want some of those i was just looking at them!!! I worked at Broan Manufacturing in Hartford Wisconsin and they make ceiling fans bathroom fans stove range hoods with fans and I can also tell you a secret....PSSSSSST I made product with Broan,Sears Kenmore, Nautilus and a few other namebrand tags and tacked boxes for shipping with all these names ;)
 
i actually want some of those i was just looking at them!!! I worked at Broan Manufacturing in Hartford Wisconsin and they make ceiling fans bathroom fans stove range hoods with fans and I can also tell you a secret....PSSSSSST I made product with Broan,Sears Kenmore, Nautilus and a few other namebrand tags and tacked boxes for shipping with all these names ;)

They aren't the only manufacturer who makes the very same items for those "NAME BRAND" stores.:whistle:
 
I had often wondered about RM amps and the RM-3 transistor value. Is there any more info or any updated info on this mystery? and what do they really put out and what input wattage and swing will they handle safely on AM and SSB...........solve the mystery?
 
I had often wondered about RM amps and the RM-3 transistor value. Is there any more info or any updated info on this mystery? and what do they really put out and what input wattage and swing will they handle safely on AM and SSB...........solve the mystery?


Nothing really has changed. An amp like a KL203 is still very much a low drive amp good for 100-150 watts depending on how you drive it. For 68 bucks it's a cheap light duty throwaway amp when it brakes.
 

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