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Transistor claims? is it real or is it "snake oil"?

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mw2000:
Hi everyone!
I hope my question about a transistor is in the right place.
This is about something called a "Max-Mod" and the regular "TIP36" regulator transistor that comes in radios when they are new.

This is my first post and I am hoping that I can "ask some experts" about this thing that several radio shop is trying to sell me as an add-on to a radio I want.
I got into electronics a year ago and I have been reading a lot of posts here and the information is overwhelming!
I have one more year of high school and I am really considering electronics as the direction I go in.
Dave's videos on choosing equipment to buy and how to set it up have been really helpful to me while I shop.

I also like to talk on CB radio and I was looking at getting a newer radio like a Stryker SR-955.
I keep reading and hearing from other CBers that these radios need new regulator transistors like a Max-Mod or they will overheat.
This Max-Mod transistor replaces a TIP36 transistor in the power supply.
I want to start working on radios but the small parts in them are a little too hard for me right now. I will probably break the radio :)

I am trying to understand some of the claims being made that seem to be in dispute depending on who you ask.

• Most Radios See a 10% Increase in Peak Power Levels
• Runs 40% Cooler than Stock Regulators

There is a critic of this transistor and has done some tests and says they can't perform like this.
There is another person that appears to be more of a televangelist than a radio repair person that is pushing to sell these really hard.
He put a video up on YouTube where he ran the transistor without a heatsink and timed how long it got to 200 degrees.
Then he switched it for the original one and did the same thing.

Here are my questions because this test where he ran it not mounted to a heatsink seemed crazy to me!
Is this the right way to test something like this? I thought the transistor would pop by not being on a heatsink?
One of these transistors is physically a lot larger than the other one. Doesn't that affect the test?
Can you really get up to 10% more power from your power supply by changing a transistor?
Can it really run 40% cooler just by changing a transistor? Why wouldn't the radio just come with it?

I emailed one of the guys that calls these "snake oil" transistors and he told me a few things that I wanted to verify.
He told me that the transistor in question is "turned on hard / saturated" in FM and SSB modes and that it won't generate much heat at full power anyway.
Another thing is that the only reason the larger transistor ran cooler in air was because of the "reduced thermal resistance" of the larger package?

In some other tests I saw they were mounted normally on the heatsink and the temperatures were virtually identical to the original TIP36 transistor.
He said that's because it's still producing roughly the same amount of heat as the original transistor?
This guy sent me some ohms law calculations and the math was right but was it? Mentioned some other equations called thermal ohms law?

The big question is, are the Max-Mod transistors really producing 40% less heat and 10% more power than the TIP36 transistors or are they "snake oil"?
How can we find out when there seems to be so many people selling these that say they work?
Are the people that call these "snake oil" just wrong or are the sellers just trying to take your money?

I will keep reading and trying to learn but I think this is over my head.
I thought it was snake oil but it took longer to get hot without a heat sink so I am torn now.

Thanks everyone !!!

wraper:
Snake oil. Heat dissipated and output power will be the same as long as it does not break operation of the device. If used without heatsink, it will be colder than transistors in smaller package since it has larger area for heat dissipation. This is some off the shelf transistor with custom marking. I guess some Chinese cheapo since it's easier to get those custom marked at factory.

"Datasheet": http://www.servicedocs.com/ARTIKELEN/50700283190001.pdf

wraper:

--- Quote from: mw2000 on June 29, 2019, 10:49:04 pm ---I keep reading and hearing from other CBers that these radios need new regulator transistors like a Max-Mod or they will overheat.

--- End quote ---
Those people need their overheated brain replaced.

mw2000:
The guy that thinks they are snake oil said that both transistors are going to be subject to the same rules.

He told me that they will dissipate about 30 watts of heat if there is a 5 amp load on it.
His values were 14 volts in, 8 volts out, and 5 amps for the 30 watts of heat.
He did say this was an example of how to get an idea how much heat the transistor will produce.

Does that make the equation ( 14 - 8 ) * 5?

P = V * I? is that correct?

How about the extra power? He (jokingly I think) told me that it can't do that unless it drew additional power from the space time continuum?
Can you get this extra power any other way?

wraper:

--- Quote from: mw2000 on June 29, 2019, 11:54:12 pm ---How about the extra power? He (jokingly I think) told me that it can't do that unless it drew additional power from the space time continuum?
Can you get this extra power any other way?

--- End quote ---
Nope. According to it's datasheet, even collector-emitter saturation voltage (voltage drop across fully opened transistor) spec is exactly the same as TIP36. So you cannot get even barely more voltage out of it even if it stays fully open.

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