Author |
Message |
747
Intermediate Member Username: 747
Post Number: 100 Registered: 8-2002
| Posted on Thursday, May 19, 2005 - 1:56 pm: |
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Is there REALLY a difference in these 2 amps in output if they have the same pills in them? Honestly? Or is the 300 just a marketing ploy for whoever is selling them to squeeze a few extra bucks out of buyers because they think they are getting a "bigger badder amp"? I'm NOT talking about on copper by the way, but rather some online auction sites out there... Anyone ever bench these two versus each other? |
Tech808
Moderator Username: Tech808
Post Number: 5792 Registered: 8-2002
| Posted on Thursday, May 19, 2005 - 2:54 pm: |
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747, Sorry never owned or used either one of them before. Hopefully one of the Copper Forum Members who has, will be able to post and answer your question. Lon Tech808 CEF808 N9OSN |
1861
Intermediate Member Username: 1861
Post Number: 194 Registered: 2-2004
| Posted on Thursday, May 19, 2005 - 4:40 pm: |
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250 & 300 is just marketing ploy by manufacturer . EXPECT AROUND 180 WATT PEO OUT OF EITHER . I USE A 250 AND LIKE IT . |
Bruce
Senior Member Username: Bruce
Post Number: 2630 Registered: 9-2003
| Posted on Thursday, May 19, 2005 - 7:31 pm: |
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1861 ...... You meen someone would LIE about a Cb amp? ....... Next will be antennas...........
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1861
Intermediate Member Username: 1861
Post Number: 195 Registered: 2-2004
| Posted on Thursday, May 19, 2005 - 8:27 pm: |
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Hard to believe -- isn,t it ? |
Yankee
Advanced Member Username: Yankee
Post Number: 565 Registered: 7-2003
| Posted on Thursday, May 19, 2005 - 9:12 pm: |
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I agree with 1861, I have seen both in operation and they both put out between 150-180 watts, The Palomar 250 my friend has is US made right here in Oklahoma City and the Palomar Elite 300 in China. The guy that has them likes both and has said that the receive preamp on the Elite 300 is a little better than the 250. |
Wolverine
Intermediate Member Username: Wolverine
Post Number: 352 Registered: 2-2003
| Posted on Friday, May 20, 2005 - 6:35 am: |
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I'm told that the marketing ploy like using the labels 250 and 300 on amps refer to total output on sideband only, but I agree with 1861, same pills, result in the same wattage for either amp, unless...... the amp is a custom built competition amp (With bigger transformers), instead of a commercially mass produced smaller amps. Wolverine. |
747
Intermediate Member Username: 747
Post Number: 101 Registered: 8-2002
| Posted on Friday, May 20, 2005 - 11:04 am: |
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Thanks guys - I appreciate the feedback on this! You just saved a friend of mine $15 (ok, it's not a lot - but it's something!) - he was shooting for a 300 but based on this info he went with the 250. |
Bruce
Senior Member Username: Bruce
Post Number: 2635 Registered: 9-2003
| Posted on Friday, May 20, 2005 - 1:24 pm: |
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When looking at how much can I get out of a amp a REALY quick way is to look at how big is the fuse? I built a 10 meter class C amp for FM ( I got the idea from a boomer 400 but its bias for class c ) and it used (4) 1446's in class C mode. Now its fuse is at 40 amps and the rule is your fuse should be 25% bigger that the max current you expect to draw. SO......... this amp was going to run 360 watts input MAX and class C at 75% efficenty about 275 out. It runs close to that |
Yankee
Advanced Member Username: Yankee
Post Number: 567 Registered: 7-2003
| Posted on Friday, May 20, 2005 - 3:46 pm: |
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Can someone help here? I've seen the listing on the various RF output transistors, how much power they put out and which ones will cross as replacements. Just can't remember which website I saw it on. |
Yankee
Advanced Member Username: Yankee
Post Number: 595 Registered: 7-2003
| Posted on Thursday, May 26, 2005 - 2:03 pm: |
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I found what I was looking for at the RF Parts site. Carl CEF-357 |
Bigbob
Senior Member Username: Bigbob
Post Number: 1934 Registered: 12-2001
| Posted on Thursday, May 26, 2005 - 9:31 pm: |
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Ok Yankee be honest,what does rfparts say about the output of the sd1446,one is for 50 megs and the other is for 27 megs,I get tired of being the only one acknowledging this.Bigbob |
Yankee
Advanced Member Username: Yankee
Post Number: 598 Registered: 7-2003
| Posted on Thursday, May 26, 2005 - 10:28 pm: |
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RF Parts site said on the SD-1446 at 27 MHz. 90 watts for each transistor, and at 50 MHz. I think it was 70 watts for each transistor. |
1861
Intermediate Member Username: 1861
Post Number: 205 Registered: 2-2004
| Posted on Friday, May 27, 2005 - 10:38 am: |
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What are the MRF455 & 2290 rated at 27 m ? |
Bruce
Senior Member Username: Bruce
Post Number: 2726 Registered: 9-2003
| Posted on Friday, May 27, 2005 - 6:48 pm: |
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http://members.tripod.com/Malzev/comp/mrf455.htm |
Bigbob
Senior Member Username: Bigbob
Post Number: 1945 Registered: 12-2001
| Posted on Saturday, May 28, 2005 - 8:05 am: |
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bruce is correct the mrf455 is a 60 watt pill,the 2sc2290 is an 80 watt devise.The maximum usable power you can get out of the mrf455 is 90 on ssb,the 2sc2290=120 on ssb,the sd1446=135 on ssb,I got 4 and am cranking 520 on ssb,oooooh I just love my amp,it is the most perfectest amp I ever owned,it gives me goose-bumps thinking about it,YEEHAW. |
1861
Intermediate Member Username: 1861
Post Number: 207 Registered: 2-2004
| Posted on Saturday, May 28, 2005 - 9:16 am: |
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Okay , so the 1446 is 10 watts higher than the 2290 ? I always thought it was the other way around . |
Yankee
Advanced Member Username: Yankee
Post Number: 600 Registered: 7-2003
| Posted on Saturday, May 28, 2005 - 10:02 am: |
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Bigbob, Which amp. are you speaking of? From what I understand the output depends on the amount of power driving it. Carl CEF-357 |
Patzerozero
Advanced Member Username: Patzerozero
Post Number: 816 Registered: 7-2004
| Posted on Saturday, May 28, 2005 - 9:03 pm: |
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bigbob-just got a 2005 rf parts catalog & see where your info on 1446's is coming from! HOWEVER, prior to tossing my 1998 rf parts catalog in the trash, it states the sd1446 is rated at 70 watts pep at 27-50 mhz & is not rated for use on hf or high vhf-low vhf only. wonder where those other 20 watts were hiding all these years? if ya ain't inta tubes, 2879's is the way to go... |
Bigbob
Senior Member Username: Bigbob
Post Number: 1950 Registered: 12-2001
| Posted on Saturday, May 28, 2005 - 11:06 pm: |
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No,it was a 2000 rfparts catalogue,prior to that year they tested and sold low-beta devises(sd1446)high-beta has higher gain and is more prone to self-ocillation at lower freqs.the higher the frequency the less difference in output between low-beta and high-beta,the 2sc2290s will put out 80 with 4 in,sd1446 90 out with 5 in and because the ceramic chip is quite a bit smaller on the 1446 it appears to be less heat resistant,my boomer 400 will do 300 out with 10 in am on ssb it peaks 530 but avgs.360,with my rf power set at 25 pep on the dx2517 and thats using a digital peak reading meter,anymore and splatter results,anymore Qs. |
Bigbob
Senior Member Username: Bigbob
Post Number: 1952 Registered: 12-2001
| Posted on Sunday, May 29, 2005 - 7:05 am: |
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You can melt the little arms off 2sc2879s just like an old buss fuse,a fiend used his txstar on his ham radio(modded for cb)variable 0 to 110 watts,one nite he forgot to turn radio down,in a split second the arms dissappeared on THOSE BIG PILLS and the tx tube went into melt down,I told him he would forget one day and POOF.But ya know this guy is so lucky,next day he went to an estate auction and picked up a Drake for fifty bucks,still in it's sealed shipping box. |
Sg569
Intermediate Member Username: Sg569
Post Number: 124 Registered: 12-2004
| Posted on Sunday, May 29, 2005 - 11:55 am: |
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some guys have all the luck |