FDA24N40F... Apparently this is the real part number of the restamped ERF9530.
Well I intend to order one and find out.
Well I intend to order one and find out.
-
You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
ERF9530 MOSFET VERSUS IRF9530 MOSFET.
- Thread starter long night
- Start date
It's all about the speed. Since these parts are characterized to function as switches, the on/off delay times are your only guide to the max RF frequency it will amplify.
Here's the delay times for the IRF520.
And here's the FDA24N40F:
The FDA part is at least four times as slow as the IRF520. Looks like you won't get any real RF gain much above 7 or 8 MHz.
Then again, don't let me discourage you from trying. I'll predict that your power gain from input to output won't be much more than about twice the drive power.
Only one way to be sure.
Oh, and about that "gentleman's agreement" thing? Just remember the math. Two men can keep a secret if one of them is dead. My personal incentive is to spread knowledge, not conceal it.
73
Here's the delay times for the IRF520.
And here's the FDA24N40F:
The FDA part is at least four times as slow as the IRF520. Looks like you won't get any real RF gain much above 7 or 8 MHz.
Then again, don't let me discourage you from trying. I'll predict that your power gain from input to output won't be much more than about twice the drive power.
Only one way to be sure.
Oh, and about that "gentleman's agreement" thing? Just remember the math. Two men can keep a secret if one of them is dead. My personal incentive is to spread knowledge, not conceal it.
73
Last edited:
Interesting note
The Rocket amps guy that uses Eric's 9530 devices stopped building for a while, rumors were that they ran out of mosfets.
Now they are going again and said that the new amps are 24 volt capable and more tolerant to higher SWR.
Yet still palamor says out of stock on erf's.
So I contacted them.
Here's the reply.
The ERF 9530 is no longer available.
Rocket is now building with this
The Rocket box RB 1942.
24 volt capable device.
Will update when I get more information.
73
Jeff
The rebrand continues.....
The Rocket amps guy that uses Eric's 9530 devices stopped building for a while, rumors were that they ran out of mosfets.
Now they are going again and said that the new amps are 24 volt capable and more tolerant to higher SWR.
Yet still palamor says out of stock on erf's.
So I contacted them.
Here's the reply.
The ERF 9530 is no longer available.
Rocket is now building with this
The Rocket box RB 1942.
24 volt capable device.
Will update when I get more information.
73
Jeff
The rebrand continues.....
Replied
The new device will replace the 9530 but it's not compatible so you will have to replace all the the ERFs with the new RB part to repair the amp.
Current cost $13.99 each from Rocket.
The new device will replace the 9530 but it's not compatible so you will have to replace all the the ERFs with the new RB part to repair the amp.
Current cost $13.99 each from Rocket.
I suspect more snake oil. Did he get the recipe from E. Lewis and now rebranding them as his own? It's hard trying to unwind the whole scam these guys are doing with all the rebranding of parts. What happened to the days where the oe number was just on the devices and we could source the part ourselves! These guys not only want the customer base to buy their amps, now they want them running back to get the brand exclusive part from them too. It's all about the money and who cares about integrity i guess.
It's the same scam the auto industry uses to make us go back to the stealership.....
Somebody did the research work I have studiously avoided. Arbitrage is a keystone of capitalism. Find something with a value that exceeds its price. Buy low, sell high, right? Yeah, the secrecy angle is annoying, but somebody figured it out. Feel free to do the same thing. The specs for the factory catalog-numbered part that was re-marked as an ERF or RB part is published, freely-available info. Nothing stopping you. It's the age of the internet. You don't even need a pile of thick data books to do the survey like in the dark ages. Semiconductor data is on the 'net now.
It's all in the numbers. The higher the voltage and current ratings, the slower a MOSFET will be. Bigger part means a gate structure with more area. Means more capacitance. Just scan all the data sheets for a rise and fall time under 25 nanoseconds, more or less. There's a disconnect between the switching on/off delay times and the 'rise time'. Haven't grasped the math there yet. Just the same, the faster the better. And the slower the spec, the lower your uppermost functional frequency will be. If you won't operate above 14 MHz, the list of prospects gets longer. And if 80 meters is all you care about, the list of possible candidates gets even longer.
73
It's all in the numbers. The higher the voltage and current ratings, the slower a MOSFET will be. Bigger part means a gate structure with more area. Means more capacitance. Just scan all the data sheets for a rise and fall time under 25 nanoseconds, more or less. There's a disconnect between the switching on/off delay times and the 'rise time'. Haven't grasped the math there yet. Just the same, the faster the better. And the slower the spec, the lower your uppermost functional frequency will be. If you won't operate above 14 MHz, the list of prospects gets longer. And if 80 meters is all you care about, the list of possible candidates gets even longer.
73