I believe this is what you are looking for. They are only 5 bucks each. Also available in beta-matched sets. Amazon product ASIN B076PT6QYX
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ERF7530 equivalent replacement?
- Thread starter k2cb
- Start date
There is another thread here on the forum talking about these.
http://www.worldwidedx.com/threads/some-new-transistors-from-palomar.221698/
http://www.worldwidedx.com/threads/some-new-transistors-from-palomar.221698/
I guess these aren't the answers the original poster was looking for. I guess he'll spend the next 10 years trying to figure out a way to purchase transistors from someone other than Eric at Palomar.
People should keep in mind that it's the money made from stuff like this that pays for the development on stuff like that new mic he came out with.
It appears this thread took hold and more information is available in this one. I have noticed in the past that some user's will keep asking the same question until some answer satisfies their original question or they give up.
Yes but CB is 27mhz not 30mhz and the old 2SC1969 had a minimum gain of 16db and the older lower wattage driver and finals in AM only radio's often had minimum gain figures in the 50db to 150db range @27mhz no less.
I would love to see the test circuit used to establish that gain. We do not have a real datasheet either we have some cut and paste document that is a little light on data!
I always thought the MRF477 was a little low on gain but this is absolutely pathetic! It is no wonder these radio's are often using 2 driving 2. On top of that I have never seen a radio with 2 driving 2 that could actually get 100w PEP per device only counting the two finals so not expecting 400w pep. I am sure you could get it for short term service but ZERO durability. The radio's chassis cold not take that power output level and the heat sink can not dissipate that much heat! Look at how many mosfets the 2970N2 had to use to get the factory rated 100w power output and have durability.
Also no mismatch swr at any give phase angle is included either and that is kind of important for rf finals. You could dead key a 2SC1969 for a couple of hours with no antenna hooked up at all and not blow it. On the other hand an SWR over 1.3:1 scares people to death and 1.5:1 is mosfet popcorn time!
What good is a 100w pep if the radio and parts can not survive at that level for long? What good is all that wattage with very little gain. In a perfect world you would want at least 4 as finals not 2 driving 2 of those to make 100 watts pep and you would absolutely need swr protection to fold back power if the swr climbed and 8 would be even better. You would need a much larger heat sink and fans. It would be even better though if they would just put a single MRF454 as the final in these radio's. We would have decent power, decent gain, and fantastic durability. It could be an HG 2879 not as durable but a lot better than non-rf mosfets. If people would accept realistic power for those radio's something like 2-4 of the RD16HHF-1 are actually RF Specific mosfets that replicate the old 2SC1969 fairly well in terms of wattage and gain. At $5 each they will not break the bank. At $5 each though that is about 5X the cost of the junk mosfets currently in use maybe as much as 10X more when you look at the huge number's OEM buy these parts in.
Oh and I am so much talking about Palomars replacement as I have not tried these yet I am talking about the cornucopia of non-rf mosfets used by all your cb radio's and black box/rice box radio's!
Those things are really expensive and most of them run on 50 volts. For a mobile not real feasible.
On Fleabay, there is a Canadian seller that has them for $132/OBO/free shipping. That means that makes it approximately $.10/watt. Woof! Of course the problem is to build a PS for 50v. Means that a 2:1 stepdown 50/60v xformer would need to be beefy enough to supply that @~30A - or better. Unregulated supply probably wont cut it. But if it could; then large bridge rectifier and then a large cap bank to keep out the ripple could make that happen. Interesting. No dangerous HV needed. Makes it far safer too.
I have some of the newer ERF-2030+ MOSFET's ....... I am going to install them in a Stryker SR955 HP with a Palomar MAX MOD .......
I'm retired and enjoy repairing / upgrading radios and amplifiers.
I need one more piece of equipment for my bench, a spectrum analyzer scope .......
Anyway, I want to see how the new ERF-2030+'s perform ...... I have had good results with the FQP 13N10's ..... and also of course the IRF520's .....
I'm retired and enjoy repairing / upgrading radios and amplifiers.
I need one more piece of equipment for my bench, a spectrum analyzer scope .......
Anyway, I want to see how the new ERF-2030+'s perform ...... I have had good results with the FQP 13N10's ..... and also of course the IRF520's .....
You are lucky. I have seen amps fry without a transmitter attached or even being keyed up.(Infantile failures do happen)
65V+ units are much better than they 50V units. You can use them in mobile application even Luke aka BBi puts them in mobile units. Ideally, a base station is an even better application. Compared to the price vs performance of bjt's they are a fantastic value. Since I have 16 bjt PCB's I am not jumping ship anytime soon.
Leapfrog 3:1 is nothing LDMOS can take anywhere from 68:1 to infinite and that is at all phase angles.
Leapfrog 3:1 is nothing LDMOS can take anywhere from 68:1 to infinite and that is at all phase angles.