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#1
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FS: Collins 32V-3 HF Transmitter NICE!!!
This has plate modulation so when you key 120 watts on AM you get about 450 Watts or so out. If you're looking for a clean 32V-3 this is it. Non smoker and it works 100 Percent!! I hardly use it. Looking for someone to pick it up locally here in Essex County NJ or you pay shipping UPS. Price: 1000.00 To read up on it, Go to: www.collinsradio.org/html/32v-3.html Reply To: |
#2
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120 watts on AM you get about 450 Watts or so out.
No seriously, what the F*** are you talking about??? wrote in message ... FS: Collins 32V-3 HF Transmitter NICE!!! This has plate modulation so when you key 120 watts on AM you get about 450 Watts or so out. If you're looking for a clean 32V-3 this is it. Non smoker and it works 100 Percent!! I hardly use it. Looking for someone to pick it up locally here in Essex County NJ or you pay shipping UPS. Price: 1000.00 To read up on it, Go to: www.collinsradio.org/html/32v-3.html Reply To: |
#3
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![]() "YT" wrote in message t... 120 watts on AM you get about 450 Watts or so out. No seriously, what the F*** are you talking about??? A 120 watt fully-modulated carrier has a PEP of about 480 watts. It really doesn't mean much... Pete |
#4
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![]() On Mon, 23 Jan 2006, Uncle Peter wrote: "YT" wrote in message t... 120 watts on AM you get about 450 Watts or so out. No seriously, what the F*** are you talking about??? A 120 watt fully-modulated carrier has a PEP of about 480 watts. It really doesn't mean much... Pete My understanding of AM transmitter technology would estimate that a 32v3, with ~120 DC input (two 6146s, or were they still using one 4D32?) would have at most (class C, plate modulated) 70% X 120 = 80 watts of CW carrier output. 60 watts of audio on that final tube (as a non-linear high level mixer) will at best, double the _instantaneous_ (peak) input voltage, therefore power to 240 watts (plate current will _not_ double even if the plate voltage doubles on peak audio cycle [look at your tube curves again of iP vs vP at constant biases]) which you could only attempt to measure with an oscilloscope. Peak output? Could it be more than 240 x 0.7 = 168 watts? I doubt it (unless he's got something like "super-modulation" in the rig). |
#5
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![]() "Straydog" wrote in message My understanding of AM transmitter technology would estimate that a 32v3, with ~120 DC input (two 6146s, or were they still using one 4D32?) would have at most (class C, plate modulated) 70% X 120 = 80 watts of CW carrier output. 60 watts of audio on that final tube (as a non-linear high level mixer) will at best, double the _instantaneous_ (peak) input voltage, therefore power to 240 watts (plate current will _not_ double even if the plate voltage doubles on peak audio cycle [look at your tube curves again of iP vs vP at constant biases]) which you could only attempt to measure with an oscilloscope. Peak output? Could it be more than 240 x 0.7 = 168 watts? I doubt it (unless he's got something like "super-modulation" in the rig). Without delving into the limitations of the 32V3, according to the info from an ARRL publication: "..since the amplitude at the peak of the upswing is twice the unmodulated amplitude, the power at this instant is four times the unmodulated, or 400 watts." Average power, on the other hand, will be 1.5 times carrier. A Class C amplifier with high level modulation should produce an instaneous PEP of 4x carrier power. Pete |
#6
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You guys are right both in facts and spirit.
" Uncle Peter" wrote in message news:6xwBf.11951$bF.2404@dukeread07... "Straydog" wrote in message My understanding of AM transmitter technology would estimate that a 32v3, with ~120 DC input (two 6146s, or were they still using one 4D32?) would have at most (class C, plate modulated) 70% X 120 = 80 watts of CW carrier output. 60 watts of audio on that final tube (as a non-linear high level mixer) will at best, double the _instantaneous_ (peak) input voltage, therefore power to 240 watts (plate current will _not_ double even if the plate voltage doubles on peak audio cycle [look at your tube curves again of iP vs vP at constant biases]) which you could only attempt to measure with an oscilloscope. Peak output? Could it be more than 240 x 0.7 = 168 watts? I doubt it (unless he's got something like "super-modulation" in the rig). Without delving into the limitations of the 32V3, according to the info from an ARRL publication: "..since the amplitude at the peak of the upswing is twice the unmodulated amplitude, the power at this instant is four times the unmodulated, or 400 watts." Average power, on the other hand, will be 1.5 times carrier. A Class C amplifier with high level modulation should produce an instaneous PEP of 4x carrier power. Pete |
#7
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On 1/24/06 12:57 PM, in article 6xwBf.11951$bF.2404@dukeread07, "Uncle
Peter" wrote: "Straydog" wrote in message My understanding of AM transmitter technology would estimate that a 32v3, with ~120 DC input (two 6146s, or were they still using one 4D32?) would have at most (class C, plate modulated) 70% X 120 = 80 watts of CW carrier output. 60 watts of audio on that final tube (as a non-linear high level mixer) will at best, double the _instantaneous_ (peak) input voltage, therefore power to 240 watts (plate current will _not_ double even if the plate voltage doubles on peak audio cycle [look at your tube curves again of iP vs vP at constant biases]) which you could only attempt to measure with an oscilloscope. Peak output? Could it be more than 240 x 0.7 = 168 watts? I doubt it (unless he's got something like "super-modulation" in the rig). Without delving into the limitations of the 32V3, according to the info from an ARRL publication: "..since the amplitude at the peak of the upswing is twice the unmodulated amplitude, the power at this instant is four times the unmodulated, or 400 watts." Average power, on the other hand, will be 1.5 times carrier. A Class C amplifier with high level modulation should produce an instaneous PEP of 4x carrier power. Pete Getting back to basics: A 120W (input) power, class C stage, will require 60W of audio (using a high-level, e.g. plate, modulator) for 100% modulation. If we assume 85% efficiency, then the output will consist of a Carrier of 102W and two sidebands of 25.5W each. In my opinion, any other explanation is useless. Do remember that the carrier amplitude does NOT vary with modulation. Don |
#8
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On Tue, 24 Jan 2006 13:40:54 -0800, Don Bowey
wrote: On 1/24/06 12:57 PM, in article 6xwBf.11951$bF.2404@dukeread07, "Uncle Peter" wrote: "Straydog" wrote in message My understanding of AM transmitter technology would estimate that a 32v3, with ~120 DC input (two 6146s, or were they still using one 4D32?) would have at most (class C, plate modulated) 70% X 120 = 80 watts of CW carrier output. 60 watts of audio on that final tube (as a non-linear high level mixer) will at best, double the _instantaneous_ (peak) input voltage, therefore power to 240 watts (plate current will _not_ double even if the plate voltage doubles on peak audio cycle [look at your tube curves again of iP vs vP at constant biases]) which you could only attempt to measure with an oscilloscope. Peak output? Could it be more than 240 x 0.7 = 168 watts? I doubt it (unless he's got something like "super-modulation" in the rig). Without delving into the limitations of the 32V3, according to the info from an ARRL publication: "..since the amplitude at the peak of the upswing is twice the unmodulated amplitude, the power at this instant is four times the unmodulated, or 400 watts." Average power, on the other hand, will be 1.5 times carrier. A Class C amplifier with high level modulation should produce an instaneous PEP of 4x carrier power. Pete Getting back to basics: A 120W (input) power, class C stage, will require 60W of audio (using a high-level, e.g. plate, modulator) for 100% modulation. If we assume 85% efficiency, then the output will consist of a Carrier of 102W and two sidebands of 25.5W each. In my opinion, any other explanation is useless. Do remember that the carrier amplitude does NOT vary with modulation. Don I don't remember the 32v3 specs but a pair of 6146B's is rated for 120 watts carrier output on AM. 6146A's are rated for 100 watts output on AM. Assuming the 120 watts carrier output, when modulated 100% the voltage doubles and the current also doubles on modulation peaks. Doubling the voltage and doubling the current works out to 4 times the power. This is of course Peak Envelope Power of the signal which would be 480 watts. You can not just add the audio power to the carrier power to find PEP. You must first add the voltages together. Peak envelope power is what the FCC is concerned with for maximum allowable power of 1500 watts. Although when advertising an AM transmitter it is common to state the carrier power and not try to confuse people by stating the PEP power and not stating that is what is being speced. 73 Gary K4FMX |
#9
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![]() "Gary Schafer" wrote in message ... Although when advertising an AM transmitter it is common to state the carrier power and not try to confuse people by stating the PEP power and not stating that is what is being speced. 73 Gary K4FMX Agreed.. I was just giving an explanation of the seller's somewhat cryptic sales pitch. Pete |
#10
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Uncle Peter wrote:
"Gary Schafer" wrote in message ... Although when advertising an AM transmitter it is common to state the carrier power and not try to confuse people by stating the PEP power and not stating that is what is being speced. 73 Gary K4FMX Agreed.. I was just giving an explanation of the seller's somewhat cryptic sales pitch. Pete How much would it be in P.M.P.O. watts? Coupla hundred kilowatts? ![]() -Bill |
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