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Palomar 450 fet linear amp ???

M42duster I have the old 250 with 2-1446's or whatever they are. I get 200 watts swing with my diamond sx-100 meter. That's running it with my CRE. Max output I get is about 200 regardless of input. With about 2 watts carrier in I get the most swing. So that's how I run it on am. Gets great reports on ssb. They all say it sounds good and clean. Although I'm sure it wouldn't look clean. My cousin has the FET 250 HD brand new. He's running it with his magnum S45HP. Gets almost exactly the same numbers. We always talk on ssb and it sounds great.
 
mdavis735 said:
M42duster I have the old 250 with 2-1446's or whatever they are. I get 200 watts swing with my diamond sx-100 meter. That's running it with my CRE. Max output I get is about 200 regardless of input. With about 2 watts carrier in I get the most swing. So that's how I run it on am. Gets great reports on ssb. They all say it sounds good and clean. Although I'm sure it wouldn't look clean. My cousin has the FET 250 HD brand new. He's running it with his magnum S45HP. Gets almost exactly the same numbers. We always talk on ssb and it sounds great.
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Tell your cousin that the S45HP is too hot of a radio for a 250 model amplifier. The ONLY way that will work is if he keeps the S45HP dialed down so it does not overdrive the amp. He would be better off getting the 450 FET with that radio.



As an example this is straight off the X-Force Amplifier web site referring to their Mosfet 400 amp. You can see they refer to the RFX75 which is what the S45HP has.


MF400 ** ON SALE **

4 Mosfet Transistors GREAT matchup for any 100 watt radio or the RFX75 board
1 built-in cooling fan
Hi/Med/Low SwitchPreamp Switch Auto-sideband delay400 watts peak power45 amp max drawDim. L 7 1/2 W 6 H 3 Input Drive: 2-18 watt carrier, 110 pep
Out of box warranty against factory defects
Export use only




Price: $220.99 Quantity:
 
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It's the high drive model. Supposedly up to 10 watts in with up to 50 swing. He runs it with a 4 or 5 watt carrier swinging 20 or 30 I think. It sounds good on ssb. So the only downside is if it smokes I guess. At $129 shipping included brand new. I guess if it smoked it wouldn't be the end of the world.
 
mdavis735 said:
It's the high drive model. Supposedly up to 10 watts in with up to 50 swing. He runs it with a 4 or 5 watt carrier swinging 20 or 30 I think. It sounds good on ssb. So the only downside is if it smokes I guess. At $129 shipping included brand new. I guess if it smoked it wouldn't be the end of the world.
Click to expand...

The S45 is an 80 watt radio, the Top Gun Modulator feature on that radio lets it hit it's peak power even with a lower carrier. The one I had would easily hit 60 watts with a 4-5 watt carrier.

Just because an amp builder says the MAX PEAK input is 50 watts that does not mean you run it at 50. The 400 or 450 mosfet is a better safer match.

:headbang :headbang:bdh::bdh: I give up
 
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I'm not sure why it would matter at all to either one of us. It's not either of our amps or radios. Someone asked a question about the Palomar amps and I stated the info I had about the only one I've seen. Numbers are numbers, but the fact is that I talk to him everyday on ssb and he sounds just like himself in person. Have no idea what it looks like on a scope. It sounds good and doesn't over heat. Haven't seen any smoke yet. Those are the only things I know about it.
 
I just got a new Palomar LD 450-FET and no matter what I do I can't get the SWR down with it on and from what my meter is showing the most I can get out of it on AM is around 300 watts. Anyone got any advice on this amp? It's the Low Drive version. And I'm using a Uniden 980SSB that dead keys around 3 watts and swings around 12.
 
Lawnmowerman427 said:
I just got a new Palomar LD 450-FET and no matter what I do I can't get the SWR down with it on and from what my meter is showing the most I can get out of it on AM is around 300 watts. Anyone got any advice on this amp? It's the Low Drive version. And I'm using a Uniden 980SSB that dead keys around 3 watts and swings around 12.
Click to expand...

that's about what they do, 300-350PEP at 13.5 to 14 volts,, my swr into the LD 450-fet is great less than 1.3:1,, you do need to use a longer 6-9' jumper from the radio to the amp or you can have issues,, mine had a document with it that stated this,,,,, I know its not right to have to do that but with the longer jumper mine works great in the mobile and has good input swr,, also this amp has a great working pre-amp,, most just make the static louder, not this one..
 
I have the original High-Drive version:

Try a long jumper between the radio and the amp.

Note: the four finals are rated at 75 watts each so 300 watts or so is normal unless your going to over-drive or over volt the amp.

My High-Drive version does 300 watts with about 100 watts drive.

.
 
I was using a 6' jumper from the radio to the amp and I switched it to a 18' jumper and the SWR went down some but it's still kinda high say a 2.5 and I'm using a Wilson 5,000 magnet mount for my antenna.
 
So the SWR is high at the antenna?

Are you out in a " clear area " away from buildings, trees, trucks and cars ?

How is the antenna mounted center of roof, trunk lid ?

Running power you may be having some reflect ?

.
 

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