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On Sat, 30 Sep 2006 02:30:28 GMT, "U-Know-Who"
wrote in : Possible, but with more distortion (oops, he calls it compression) than he claims. http://www.telstar-electronics.com/SkyWave%202879AB.pdf Now was that all so hard, Brian? Did you peruse some websites to rethink your internet theories? "LOL" ROTFL! And after being completely humiliated in public because he can't read a simple x-y graph, it now gets worse because he didn't even go back to check his OWN graph: He measured (or so he claims) his "1dB compression point" with an unmodulated carrier. An unmodulated carrier is the same as PEP (as well as CW). He doesn't even realize that his 129 watt "measurement" is the very same "compression point" that he must use to rate SSB power. So it's 129 watts PEP @ 1dB compression, not 322 watts! So where did he get 322 watts? You know he didn't measure it or he would have used the actual measurement the first time. Well, this shouldn't come as a big suprise, but 322 watts is ALMOST EXACTLY 2dB down from his original fish-story of 516 watts. So much for his 'revised' power rating..... "LOL"!!! |
#2
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So much for his 'revised' power rating..... "LOL"!!!
It has changed once again. Apparently his amp isn't as stable as he claims. |
#3
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Premium Quality PC Board, Components and Chassis
13.8VDC 10 Meter Amateur Radio Band Coverage All Mode (CW, AM, FM, SSB) Toshiba 2SC2879 Push-Pull Configuration with Beta/Gain Matched Transistors Regulated Class-AB Biasing High Output Power High Efficiency Heat Sink Polarized Detachable Power Cord Fuse Protected Extremely Low Stand-By Power Remote Operation Ready Carrier Operated Relay (COR) or Multiplexed Keying† SSB Delay to Eliminate Relay Chatter High Reliability Design Low Harmonic Content 90 Day Limited Warranty † Contact Telstar Electronics for details on using this feature www.telstar-electronics.com |
#4
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On 30 Sep 2006 13:32:13 -0700, "Telstar Electronics"
wrote in . com: Premium Quality PC Board, Components and Chassis 13.8VDC 10 Meter Amateur Radio Band Coverage All Mode (CW, AM, FM, SSB) Toshiba 2SC2879 Push-Pull Configuration with Beta/Gain Matched Transistors Regulated Class-AB Biasing High Output Power High Efficiency Heat Sink Polarized Detachable Power Cord Fuse Protected Extremely Low Stand-By Power Remote Operation Ready Carrier Operated Relay (COR) or Multiplexed Keying† SSB Delay to Eliminate Relay Chatter High Reliability Design Low Harmonic Content 90 Day Limited Warranty † Contact Telstar Electronics for details on using this feature www.telstar-electronics.com Hey Brian..... Since the transistors you are using are rated for a typical gain of 15.2dB, and you are using two of them, why is your amp rated for only 15dB instead of 18.2dB? And at 18.2dB, if you shove in a typical 4 watt carrier from a CB, doesn't that put your AM "RMS" output about 264 watts? (And your PEP output at 1056 watts?) Now assuming you have a magical amp that can achieve 55% efficiency irrespective of the 35% collector efficiency of the transistor, when you 100% modulate this 264 watt carrier (giving an AVERAGE power 396 watts), doesn't that mean you are going to be drawing 720 watts from your power supply? Just in case I missed something in 3rd-grade math you better check my work he 720 watts / 15 volts = 48 amps. You also have a base-bias current of 1 amp for each transistor, so 48 + 2 = 50 amps. Right? But who uses a 15 volt power supply? Heck, we'll use the more common automotive standard of 13.8 volts. So 720 / 13.8 = 52.2 amps, plus 2 amps = 54.2 amps. HOLD ON A SEC.... Your amp only has a 30 amp fuse!!! So after I get this all hooked up, wired directly to my battery and everything, plug in my favorite little 4-watt CB, this amp is going to blow a fuse every time I yell "A-U-D-I-O" into the mic. Ok, I bypass the fuse and switch my CB on SSB with 12 watts PEP. What's going to melt first -- the transistors or the power leads? And you call this a "High Reliability Design"....."LOL"!!! |
#5
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#6
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Premium Quality PC Board, Components and Chassis
13.8VDC 10 Meter Amateur Radio Band Coverage All Mode (CW, AM, FM, SSB) Toshiba 2SC2879 Push-Pull Configuration with Beta/Gain Matched Transistors Regulated Class-AB Biasing High Output Power High Efficiency Heat Sink Polarized Detachable Power Cord Fuse Protected Extremely Low Stand-By Power Remote Operation Ready Carrier Operated Relay (COR) or Multiplexed Keying† SSB Delay to Eliminate Relay Chatter High Reliability Design Low Harmonic Content 90 Day Limited Warranty † Contact Telstar Electronics for details on using this feature www.telstar-electronics.com |
#7
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#8
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#9
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On 30 Sep 2006 15:07:00 -0700, "Telstar Electronics"
wrote in . com: Premium Quality PC Board, Components and Chassis 13.8VDC 10 Meter Amateur Radio Band Coverage All Mode (CW, AM, FM, SSB) Toshiba 2SC2879 Push-Pull Configuration with Beta/Gain Matched Transistors Regulated Class-AB Biasing High Output Power High Efficiency Heat Sink Polarized Detachable Power Cord Fuse Protected Extremely Low Stand-By Power Remote Operation Ready Carrier Operated Relay (COR) or Multiplexed Keying† SSB Delay to Eliminate Relay Chatter High Reliability Design Low Harmonic Content 90 Day Limited Warranty † Contact Telstar Electronics for details on using this feature www.telstar-electronics.com Awww.... ain't that cute..... he's POUTING!!! |
#10
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On 30 Sep 2006 15:07:00 -0700, "Pouting Brian"
wrote in . com: On Sat, 30 Sep 2006 14:24:22 -0700, Frank Gilliland wrote in : Hey Brian..... Since the transistors you are using are rated for a typical gain of 15.2dB, and you are using two of them, why is your amp rated for only 15dB instead of 18.2dB? Because I attenutated the input, which gives the amp an overall gain of 15dB. Well that doesn't make sense -- why use two transistors in an amp that can be built with one? Aren't you the one that's always worried about it being too expensive? HOLD ON A SEC.... Your amp only has a 30 amp fuse!!! So after I get this all hooked up, wired directly to my battery and everything, plug in my favorite little 4-watt CB, this amp is going to blow a fuse every time I yell "A-U-D-I-O" into the mic. You are a real idiot if you don't know about slo-blow fuses. I took that into account, Pouting Brian. That's why I calculated AVERAGE power and not PEAK (PEP) power, just like it was outlined in your favorite educational website. Ok, I bypass the fuse and switch my CB on SSB with 12 watts PEP. What's going to melt first -- the transistors or the power leads? Your brain, but it melted a long time ago. Good comeback, Pouting Brian..... I feel like I have been dissed by the best...."LOL"!!! And you call this a "High Reliability Design"....."LOL"!!! Where's your amp, Frank? That's what it all boils down to with you, isn't it? You get up on the stage and sing like a rutting moose. When you are done, the audience stops grimmacing and takes their fingers out of their ears, and they begin their criticism. You can't take it so you try to turn your lack of ability onto them by saying, "Let's hear YOU sing." A classic 'sour grapes' response. You built an amp without any engineering ability and it shows. If you don't like the criticism, get off the stage. Otherwise, get ready for the rotten tomatos because there are plenty more things I can pick apart about your amp from your spec sheet..... for example, did you know that total harmonic distortion can be calculated from an amp's nonlinear response? And guess what: you posted the curve! So get ready for round 2....."LOL"!!! |
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