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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!

<blockquote data-quote="Onelasttime" data-source="post: 608735" data-attributes="member: 21190">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&#039;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&#039;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&#039;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&nbsp; as the final in these radio&#039;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&#039;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&#039;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&#039;s and black box/rice box radio&#039;s!</blockquote>

[QUOTE="Onelasttime, post: 608735, member: 21190"] 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! [/QUOTE]

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