Re: [Elecraft] 100 Watts or 500 Watts
As a recent K3/P3 kit assemblier(4910) and an old timer (licenced in '47). I'm still trying to understand all the nuiances of the K3 operation. Thank you, the Elecraft Reflector, for all the good ideas and help. But as I understand it, the quote of the HF DX'rs is " Life is too short for QRP", 500 Watts. So my New Years and B'Day (79) present next month will be a 2nd hand but good working AL 1500. I really like 8877s. I worked WAS, WAC, VUCC, and 95 DXCCs on 2M with one, using CW. So maybe I'll try a bit of HF for a change with my K3/100. BTW, it should also make and excelent EME transceiver, especially with the purposed extenal 10MHz driven REF Lock module. GL es 73, Chuck, W7CS __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] 100 Watts or 500 Watts
I have worked as a BC engineer and I'm very, very careful. In addition to following work procedures like the use of a 'shorting stick', there are various design principles important for safety. There should never be a way for someone to come into contact with HV, no matter what component or combination thereof fails (within reason, of course). Just for example: you often see a 'safety' RF choke across the output of a pi-network. Supposedly this will cause a fuse to blow if the plate blocking capacitor breaks down and puts HV on the antenna. But most such chokes are too puny -- they will blow before the fuse! Interconnections between remote power supplies and RF decks are another risky area. I prefer to put it all in one box, or at least an enclosed rack. I only work on such projects when I am feeling 1) alert and 2) patient. 'Patient' is really important. If you are operating in the 'every time I try to fix something I break something else' mode, then STOP. I like to spend a lot of time thinking about what I'm about to do before doing it. This is getting off-topic for the reflector, so this will be my last post on the subject! On 12/22/2010 11:36 AM, Ron D'Eau Claire wrote: > Good point George. The question was specifically about the 813 and it's a > "nostalgia bottle" for many of us. It was popular after WWII because you > could get them for as little as 50 cents each in the USA. Even in the 60's > they were still available 'surplus' for a few dollars. Typically the socket > cost far more than the tube. > > The biggest cost in a tube amp is in the power supply (including high > voltage hardware) and in the input/output network components that can handle > the voltages involved. > > You can avoid those costs by buying a used amp, even if it's not functional > (but hopefully has a good power transformer). > > Other than learning to work around thousands of volts (only one mistake > allowed per lifetime) tube amps are extremely simple things compared to most > high power solid state amps. And tubes tend to be much more tolerant of > abuse than solid state. > > But that comment about only one mistake allowed per lifetime around the > typical tube amp power supply was serious. I'm always very cautious about > encouraging today's typical ham to mess around with even moderate or low > power tube gear if he/she has "grown up" around solid state running from a > few tens of volts at the most. One needs a wholly different set of > procedures, concerns and attitudes to work around even a few hundred volts > safely. > > Over the years we've lost a number of wonderful, bright, prolific designers > and builders in the Ham community to one momentary mis-step around a high > voltage power supply. > > Ron AC7AC > > > -Original Message- > > Just some simple questions. Why use an 813 for an amp. 125 watt plate > dissipation, 50 watts of heater power, and a large physical size. The > "modern" > 572b uses 25 watts for heater power has 225 watts dissipation and is cheap. > I > have two SB200s they put out 800 watts PEP and they can be bought real > inexpensive. Every couple of years I stick new tubes in them for kicks and > use > the pulls as spares or "presents". > > I love building, but I am practical too. But have fun guys and please be > careful. > > George, W6GF > > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html -- Vic, K2VCO Fresno CA http://www.qsl.net/k2vco/ __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] 100 Watts or 500 Watts
Good point George. The question was specifically about the 813 and it's a "nostalgia bottle" for many of us. It was popular after WWII because you could get them for as little as 50 cents each in the USA. Even in the 60's they were still available 'surplus' for a few dollars. Typically the socket cost far more than the tube. The biggest cost in a tube amp is in the power supply (including high voltage hardware) and in the input/output network components that can handle the voltages involved. You can avoid those costs by buying a used amp, even if it's not functional (but hopefully has a good power transformer). Other than learning to work around thousands of volts (only one mistake allowed per lifetime) tube amps are extremely simple things compared to most high power solid state amps. And tubes tend to be much more tolerant of abuse than solid state. But that comment about only one mistake allowed per lifetime around the typical tube amp power supply was serious. I'm always very cautious about encouraging today's typical ham to mess around with even moderate or low power tube gear if he/she has "grown up" around solid state running from a few tens of volts at the most. One needs a wholly different set of procedures, concerns and attitudes to work around even a few hundred volts safely. Over the years we've lost a number of wonderful, bright, prolific designers and builders in the Ham community to one momentary mis-step around a high voltage power supply. Ron AC7AC -Original Message- Just some simple questions. Why use an 813 for an amp. 125 watt plate dissipation, 50 watts of heater power, and a large physical size. The "modern" 572b uses 25 watts for heater power has 225 watts dissipation and is cheap. I have two SB200s they put out 800 watts PEP and they can be bought real inexpensive. Every couple of years I stick new tubes in them for kicks and use the pulls as spares or "presents". I love building, but I am practical too. But have fun guys and please be careful. George, W6GF __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] 100 Watts or 500 Watts
I will throw out another opinion about amplifier gain that has nothing to do with CB or IMD. If an operator is currently running QRP at 10, 5 or less watts, adding the KPA-3 to boost power to 100 watts will give you a very large power boost and will be enough power for a lot of QSOs, both domestic and DX. You can still turn the K-3 down to 100 mw if you want to give your antennas and patience the acid test. If you add a 500 watt or bigger amplifier you have another nice boost in power and you have a combination that will give you smooth power increases from 100 mw to 500 watts or with a bigger amp the legal limit. To my way of thinking, this is a better combination than trying to solve the problems of home brewing or modifing a commercial amp. Food for thought? Willis 'Cookie' Cooke K5EWJ __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] 100 Watts or 500 Watts
Just some simple questions. Why use an 813 for an amp. 125 watt plate dissipation, 50 watts of heater power, and a large physical size. The "modern" 572b uses 25 watts for heater power has 225 watts dissipation and is cheap. I have two SB200s they put out 800 watts PEP and they can be bought real inexpensive. Every couple of years I stick new tubes in them for kicks and use the pulls as spares or "presents". I love building, but I am practical too. But have fun guys and please be careful. George, W6GF From: Ron D'Eau Claire To: Sent: Wed, December 22, 2010 9:20:47 AM Subject: Re: [Elecraft] 100 Watts or 500 Watts Time to dig out some old ARRL Handbooks from the 60's. My '62 Handbook has a nice 813 grid driven amp that runs Class C for CW and AB2 for SSB, the famous "one band kilowatt" amplifiers using a pair of 813's (each band had its own RF 'deck' with a common power and metering circuit so each amp could be pre-tuned and ready to go at the snap of a relay or switch) and a Kilowatt grid-driven 4-400A amp, in addition to the usual assortment of ground grid amps. A builder today may need to 'beef up' the pi-network output filter to meet modern spurious emission standards (typically for the second harmonic) or use an outboard half-wave filter for each band for that purpose. Ron (radios should glow in the dark) AC7AC -Original Message- On 12/22/2010 11:30 AM, a lister wrote: Grounded-grid is not the only way to design a tube amplifier. Although a traditional grid-driven circuit is a little more complicated, it's one way to get more gain. Amen to that. When I was little, "grounded grid" was vaunted as the way to use triodes without needing neutralization, even though one took a real hit on gain. Unfortunately, the old-time big amps that use/used several triodes in parallel in grounded grid still have a tendency to "take off." The 813 and the various Eimac ceramic tetrodes are wonderful tubes, and if one can go high voltage low current, they are excellent performers. Again, when I was young, solid state devices wouldn't function in the VHF/UHF region, and the 4CXnnn series were practically a necessity. Need I refer to the beautiful amps vended by one of the early moonbounce guys? I for one would like to see designs using these tubes. Not all of us need linear/linearized amps. John Ragle -- W1ZI __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] 100 Watts or 500 Watts
My approach to the harmonic problem is to use a link-coupled antenna tuner on 80-30 meters (Johnson Matchbox), and a homebrew parallel tuned circuit on 160. On the higher bands, the simple pi network should be adequate to keep the harmonics down. You could use a pi-L configuration on the low bands if you wish. A bigger problem with class-C is how to keep the high bias from sharpening up the beautiful K3 keying and producing clicks. My approach is to have the QSK circuit drop the bias below cutoff when the amplifier is keyed, so that the amplifier is initially operating in the linear part of the curve. There is a resistor in the grid circuit which supplies the remainder of the class-C bias from rectified grid current. But that bias rises along with the drive. The bypass capacitor and this resistor form a filter which keeps the transition to full power clean. On 12/22/2010 9:20 AM, Ron D'Eau Claire wrote: > Time to dig out some old ARRL Handbooks from the 60's. My '62 Handbook has a > nice 813 grid driven amp that runs Class C for CW and AB2 for SSB, the > famous "one band kilowatt" amplifiers using a pair of 813's (each band had > its own RF 'deck' with a common power and metering circuit so each amp could > be pre-tuned and ready to go at the snap of a relay or switch) and a > Kilowatt grid-driven 4-400A amp, in addition to the usual assortment of > ground grid amps. > > A builder today may need to 'beef up' the pi-network output filter to meet > modern spurious emission standards (typically for the second harmonic) or > use an outboard half-wave filter for each band for that purpose. > > Ron (radios should glow in the dark) AC7AC > > -Original Message- > On 12/22/2010 11:30 AM, a lister wrote: > > Grounded-grid is not the only way to design a tube amplifier. Although a > traditional grid-driven circuit is a little more complicated, it's one way > to get more gain. > > Amen to that. When I was little, "grounded grid" was vaunted as the way to > use triodes without needing neutralization, even though one took a real hit > on gain. Unfortunately, the old-time big amps that use/used several triodes > in parallel in grounded grid still have a tendency to "take off." > > The 813 and the various Eimac ceramic tetrodes are wonderful tubes, and if > one can go high voltage low current, they are excellent performers. Again, > when I was young, solid state devices wouldn't function in the VHF/UHF > region, and the 4CXnnn series were practically a necessity. Need I refer to > the beautiful amps vended by one of the early moonbounce guys? > > I for one would like to see designs using these tubes. Not all of us need > linear/linearized amps. > > John Ragle -- W1ZI -- Vic, K2VCO Fresno CA http://www.qsl.net/k2vco/ __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] 100 Watts or 500 Watts
On Wed, Dec 22, 2010 at 10:45 AM, John Ragle wrote: > On 12/22/2010 11:30 AM, a lister wrote: > > ...When I was little, "grounded grid" was vaunted as the way to use triodes > without needing neutralization... Yep. Remember the bifilar filament chokes? You could go to the ham store, get one of those, a cool litz-wound plate choke, and a bandswitching tank coil, and the variables you needed for a pi-network output, and build a heck of an amp. Another way was the NCL-2000 way, wherein the input circuit was just a 50 ohm resistor and the amp ran in class AB1, using 8122 ceramic tubes. IIRC, about 50 watts of drive was enough. An amp designed that way could use a higher value resistor, show the transceiver a mismatch, and get by with less drive. If you used a 200 ohm resistor and a 4:1 balun, you could probably drive such an amp to the max with 10-15 watts, no step-up stage required. Tony KT0NY __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] 100 Watts or 500 Watts
Time to dig out some old ARRL Handbooks from the 60's. My '62 Handbook has a nice 813 grid driven amp that runs Class C for CW and AB2 for SSB, the famous "one band kilowatt" amplifiers using a pair of 813's (each band had its own RF 'deck' with a common power and metering circuit so each amp could be pre-tuned and ready to go at the snap of a relay or switch) and a Kilowatt grid-driven 4-400A amp, in addition to the usual assortment of ground grid amps. A builder today may need to 'beef up' the pi-network output filter to meet modern spurious emission standards (typically for the second harmonic) or use an outboard half-wave filter for each band for that purpose. Ron (radios should glow in the dark) AC7AC -Original Message- On 12/22/2010 11:30 AM, a lister wrote: Grounded-grid is not the only way to design a tube amplifier. Although a traditional grid-driven circuit is a little more complicated, it's one way to get more gain. Amen to that. When I was little, "grounded grid" was vaunted as the way to use triodes without needing neutralization, even though one took a real hit on gain. Unfortunately, the old-time big amps that use/used several triodes in parallel in grounded grid still have a tendency to "take off." The 813 and the various Eimac ceramic tetrodes are wonderful tubes, and if one can go high voltage low current, they are excellent performers. Again, when I was young, solid state devices wouldn't function in the VHF/UHF region, and the 4CXnnn series were practically a necessity. Need I refer to the beautiful amps vended by one of the early moonbounce guys? I for one would like to see designs using these tubes. Not all of us need linear/linearized amps. John Ragle -- W1ZI __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] 100 Watts or 500 Watts
For linear purposes, 813's work in grounded grid with the screen tied to the control grid and grounded. You can also make a class AB1 amplifier with a 'grid circuit' consisting of a big 50-ohm dummy load. And then there is the G2DAF circuit, in which the screen voltage is derived fom the drive -- but I only recommend this one for SSB if you have a means for checking IMD; it may require some careful adjustment. I'll put up the report on my amp soon. I need to redraw the schematics which are a horrible mess at present. On 12/22/2010 8:30 AM, Dale Parfitt wrote: > Hi Vic, > Dave Ishmael has a single 813 amplifeir in this month's Electric Radio. > Please do publish > your amp for all of us to look at. I still have an 813 and socket I have had > since I was a > kid- maybe it's time to build an amp for my Atlas 350XL. > > Dale W4OP > - Original Message - From: "Vic K2VCO" > To: > Sent: Wednesday, December 22, 2010 11:14 AM > Subject: Re: [Elecraft] 100 Watts or 500 Watts > > >> I just finished building a grid-driven amplifier using two 813 tubes. With a >> 3 db >> attenuator at the input, it requires between 16 and 40 watts of drive on 160 >> through 10 >> meters respectively, for 800 watts output (only 700 on 10). Without the >> attenuator, it >> would need 8 - 20 watts drive. >> >> And this is a class-C amplifier designed for CW only! If it were a class B >> or AB linear, >> the drive requirement would be even lower. >> >> Grounded-grid is not the only way to design a tube amplifier. Although a >> traditional >> grid-driven circuit is a little more complicated, it's one way to get more >> gain. >> >> I am going to put some pictures and schematics on my web site soon, not that >> I think >> anyone will want to duplicate it! >> >> On 12/22/2010 7:50 AM, Ron D'Eau Claire wrote: >>> Even the Elecraft 100 watt amps are integrated with either the K2 or K3 >>> control logic so they cannot be used as a stand-alone amplifier with other >>> transmitters. >>> >>> The only reason I have ever seen from the FCC for the amplifier >>> certification and 15 dB gain limitation is to discourage the CB >>> 'bootleggers'. Certainly building a stable, clean amplifier that would take >>> even a few milliwatts to 1000+ watts is a straightforward design exercise. >>> There's no real problem with using more than one stage of gain if there was >>> no 15 dB limit on the system gain. >>> >>> Ron AC7AC >> >> -- >> Vic, K2VCO >> Fresno CA >> http://www.qsl.net/k2vco/ >> __ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:Elecraft@mailman.qth.net >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html > > > > > > > No virus found in this incoming message. > Checked by AVG - www.avg.com > Version: 9.0.872 / Virus Database: 271.1.1/3331 - Release Date: 12/22/10 > 02:34:00 > -- Vic __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] 100 Watts or 500 Watts
On 12/22/2010 11:30 AM, a lister wrote: Grounded-grid is not the only way to design a tube amplifier. Although a traditional grid-driven circuit is a little more complicated, it's one way to get more gain. Amen to that. When I was little, "grounded grid" was vaunted as the way to use triodes without needing neutralization, even though one took a real hit on gain. Unfortunately, the old-time big amps that use/used several triodes in parallel in grounded grid still have a tendency to "take off." The 813 and the various Eimac ceramic tetrodes are wonderful tubes, and if one can go high voltage low current, they are excellent performers. Again, when I was young, solid state devices wouldn't function in the VHF/UHF region, and the 4CXnnn series were practically a necessity. Need I refer to the beautiful amps vended by one of the early moonbounce guys? I for one would like to see designs using these tubes. Not all of us need linear/linearized amps. John Ragle -- W1ZI __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] 100 Watts or 500 Watts
Hi Vic, Dave Ishmael has a single 813 amplifeir in this month's Electric Radio. Please do publish your amp for all of us to look at. I still have an 813 and socket I have had since I was a kid- maybe it's time to build an amp for my Atlas 350XL. Dale W4OP - Original Message - From: "Vic K2VCO" To: Sent: Wednesday, December 22, 2010 11:14 AM Subject: Re: [Elecraft] 100 Watts or 500 Watts >I just finished building a grid-driven amplifier using two 813 tubes. With >a 3 db > attenuator at the input, it requires between 16 and 40 watts of drive on > 160 through 10 > meters respectively, for 800 watts output (only 700 on 10). Without the > attenuator, it > would need 8 - 20 watts drive. > > And this is a class-C amplifier designed for CW only! If it were a class B > or AB linear, > the drive requirement would be even lower. > > Grounded-grid is not the only way to design a tube amplifier. Although a > traditional > grid-driven circuit is a little more complicated, it's one way to get more > gain. > > I am going to put some pictures and schematics on my web site soon, not > that I think > anyone will want to duplicate it! > > On 12/22/2010 7:50 AM, Ron D'Eau Claire wrote: >> Even the Elecraft 100 watt amps are integrated with either the K2 or K3 >> control logic so they cannot be used as a stand-alone amplifier with >> other >> transmitters. >> >> The only reason I have ever seen from the FCC for the amplifier >> certification and 15 dB gain limitation is to discourage the CB >> 'bootleggers'. Certainly building a stable, clean amplifier that would >> take >> even a few milliwatts to 1000+ watts is a straightforward design >> exercise. >> There's no real problem with using more than one stage of gain if there >> was >> no 15 dB limit on the system gain. >> >> Ron AC7AC > > -- > Vic, K2VCO > Fresno CA > http://www.qsl.net/k2vco/ > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.872 / Virus Database: 271.1.1/3331 - Release Date: 12/22/10 02:34:00 __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] 100 Watts or 500 Watts
I just finished building a grid-driven amplifier using two 813 tubes. With a 3 db attenuator at the input, it requires between 16 and 40 watts of drive on 160 through 10 meters respectively, for 800 watts output (only 700 on 10). Without the attenuator, it would need 8 - 20 watts drive. And this is a class-C amplifier designed for CW only! If it were a class B or AB linear, the drive requirement would be even lower. Grounded-grid is not the only way to design a tube amplifier. Although a traditional grid-driven circuit is a little more complicated, it's one way to get more gain. I am going to put some pictures and schematics on my web site soon, not that I think anyone will want to duplicate it! On 12/22/2010 7:50 AM, Ron D'Eau Claire wrote: > Even the Elecraft 100 watt amps are integrated with either the K2 or K3 > control logic so they cannot be used as a stand-alone amplifier with other > transmitters. > > The only reason I have ever seen from the FCC for the amplifier > certification and 15 dB gain limitation is to discourage the CB > 'bootleggers'. Certainly building a stable, clean amplifier that would take > even a few milliwatts to 1000+ watts is a straightforward design exercise. > There's no real problem with using more than one stage of gain if there was > no 15 dB limit on the system gain. > > Ron AC7AC -- Vic, K2VCO Fresno CA http://www.qsl.net/k2vco/ __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] 100 Watts or 500 Watts
Even the Elecraft 100 watt amps are integrated with either the K2 or K3 control logic so they cannot be used as a stand-alone amplifier with other transmitters. The only reason I have ever seen from the FCC for the amplifier certification and 15 dB gain limitation is to discourage the CB 'bootleggers'. Certainly building a stable, clean amplifier that would take even a few milliwatts to 1000+ watts is a straightforward design exercise. There's no real problem with using more than one stage of gain if there was no 15 dB limit on the system gain. Ron AC7AC -Original Message- Igor, I think, at least in part, the regulation is intended to make amateur amplifiers less attractive to users of the Citizen's Radio Service. Rather than being able to go from 5W to 1000+W with a single, relatively inexpensive amp, an amp to get from 5W to ~100W is needed in order to drive the KW amp.. And except for Elecraft, I'm not aware of any other 5->100W amplifiers. 73, Dave KQ3T __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] 100 Watts or 500 Watts
Igor, I think, at least in part, the regulation is intended to make amateur amplifiers less attractive to users of the Citizen's Radio Service. Rather than being able to go from 5W to 1000+W with a single, relatively inexpensive amp, an amp to get from 5W to ~100W is needed in order to drive the KW amp.. And except for Elecraft, I'm not aware of any other 5->100W amplifiers. 73, Dave KQ3T On 12/22/2010 1:29 AM, Igor Kosvin wrote: > Is there any technical merit behind FCC's 15dB amp gain limitation? I saw > commercial RF amplifiers with gains up to 30dB, obviously approved by FCC. I > could understand the limitation for tube amplifiers, the characteristics of > some amp tubes would make high gain unstable. But for solid state amplifiers > the limitation looks strange to say the least. Maybe it's time to ask FCC to > reconsider this. Any ARRL lawyers out there? > 73, > Igor, N1YX > __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] 100 Watts or 500 Watts
Is there any technical merit behind FCC's 15dB amp gain limitation? I saw commercial RF amplifiers with gains up to 30dB, obviously approved by FCC. I could understand the limitation for tube amplifiers, the characteristics of some amp tubes would make high gain unstable. But for solid state amplifiers the limitation looks strange to say the least. Maybe it's time to ask FCC to reconsider this. Any ARRL lawyers out there? 73, Igor, N1YX -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Don Wilhelm Sent: Monday, December 20, 2010 3:31 PM To: able2...@aol.com Cc: elecraft@mailman.qth.net; d...@w3fpr.com Subject: Re: [Elecraft] 100 Watts or 500 Watts Bill, It is not an Elecraft choice. While you could do that as an individual, commercial products (sold in the US) must meet the FCC requirement of a 15 dB maximum gain That limits the maximum power gain to a factor of 31.62 - 10 watts in gives 316.2 watts (at the most) output. 73, Don W3FPR On 12/20/2010 3:23 PM, able2...@aol.com wrote: > Why wouldn't Elecraft design the KPA500 to be driven to its rated output by a K3/10 ? > > Bill K3UJ > > > > > > > -Original Message- > From: Don Wilhelm > Subject: Re: [Elecraft] 100 Watts or 500 Watts > > >Frank, > If you think you want 500 watts out, you will have to install the KPA3 > 100 watts) anyway. The K3/10 will not be able to drive the KPA500 to > ull output - you may be able to get somewhere betwen 200 and 300 watts > ut of it. > 73, > on W3FPR > > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] 100 Watts or 500 Watts
>From my copy of the ARRL FCC Rules and Regulations for the Amateur Radio Service, parts 97 and 47 of the Cod of Federal Regulations, 2007: 97.317 Standards for certification of external RF power amplifiers (a) To receive a grant of certification, the amplifier must: (2) Not be capable of amplifying the input RF power (driving signal) by more than 15 dB gain. Gain is defined as the ratio of the input RF power to the output RF power of the amplifier where both power measurements are expressed in peak envelope power or mean power. 73, Byron N6NUL On Mon, Dec 20, 2010 at 1:20 PM, Don Wilhelm wrote: > My understanding is only that the FCC says 15 > dB is the maximum, and I expect Elecraft will comply with that. -- - Northern California Contest Club - CU in the 2011 Cal QSO Party 1-2 Oct 2011 - www.cqp.org __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] 100 Watts or 500 Watts
Dale, I am not going to question the legality of the 18 dB gain you are getting on that SPE nor what the SPE documents filed with the FCC say about the maximum gain - Mu understanding is only that the FCC says 15 dB is the maximum, and I expect Elecraft will comply with that. What other companies do is not a concern of mine - I am not in any enforcement role. 73, Don W3FPR On 12/20/2010 3:49 PM, Dale Parfitt wrote: > Hi Don, > I use my SPE Expert 1K-FA with my barefoot K3. I get around 900Wout on HF > and about 500W on 6M. It's a great combination as the K3 talks to the SPE > and everything is transparent including the SPE's built in autotuner. > The SPE display reports over 18dB gain. It has been type accepted and sold > by SteppIR. > __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] 100 Watts or 500 Watts
Hi Don, I use my SPE Expert 1K-FA with my barefoot K3. I get around 900Wout on HF and about 500W on 6M. It's a great combination as the K3 talks to the SPE and everything is transparent including the SPE's built in autotuner. The SPE display reports over 18dB gain. It has been type accepted and sold by SteppIR. Dale W4OP > Bill, > > It is not an Elecraft choice. > While you could do that as an individual, commercial products (sold in > the US) must meet the FCC requirement of a 15 dB maximum gain That > limits the maximum power gain to a factor of 31.62 - 10 watts in gives > 316.2 watts (at the most) output. > > 73, > Don W3FPR > > On 12/20/2010 3:23 PM, able2...@aol.com wrote: >> Why wouldn't Elecraft design the KPA500 to be driven to its rated output >> by a K3/10 ? >> >> Bill K3UJ >> >> >> >> >> >> >> -Original Message- >> From: Don Wilhelm >> Subject: Re: [Elecraft] 100 Watts or 500 Watts >> >> >>Frank, >> If you think you want 500 watts out, you will have to install the KPA3 >> 100 watts) anyway. The K3/10 will not be able to drive the KPA500 to >> ull output - you may be able to get somewhere betwen 200 and 300 watts >> ut of it. >> 73, >> on W3FPR >> >> __ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:Elecraft@mailman.qth.net >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html >> > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.872 / Virus Database: 271.1.1/3327 - Release Date: 12/20/10 02:34:00 __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] 100 Watts or 500 Watts
Hi, Not so sure. That would require the 12W (pre)amp in the K3 to run full tilt. I seem to remember from the QST review of the K3/10 that it wasn't super clean at full power either. It's well known that both these amps get significantly cleaner when run at 50% or less which is what they would do driving the KPA500 to full power. AB2TC - Knut Rick Dettinger-3 wrote: > > But going directly from the K3/10 to the KPA500 might be a good way > for those unhappy with the SSB transmit quality of the KPA3 to get a > very clean signal since the KPA500 uses 70 volt devices for the final > amplifiers. Plus a 3 db. gain over the KPA3. At a cost, of course. > > 73, > Rick Dettinger K7MW > > > -- View this message in context: http://elecraft.365791.n2.nabble.com/100-Watts-or-500-Watts-tp5853336p5853704.html Sent from the Elecraft mailing list archive at Nabble.com. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] 100 Watts or 500 Watts
Not legal in the United States. 15 db gain is the max allowed. The hams get punished for the illegal activity of others. 73, Rick Dettinger K7MW > > Why wouldn't Elecraft design the KPA500 to be driven to its rated > output by a K3/10 ? > > Bill K3UJ > > > > > > Please help support this email list: http://www.qsl.net/donate.html __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] 100 Watts or 500 Watts
But going directly from the K3/10 to the KPA500 might be a good way for those unhappy with the SSB transmit quality of the KPA3 to get a very clean signal since the KPA500 uses 70 volt devices for the final amplifiers. Plus a 3 db. gain over the KPA3. At a cost, of course. 73, Rick Dettinger K7MW > Frank, > > If you think you want 500 watts out, you will have to install the KPA3 > (100 watts) anyway. The K3/10 will not be able to drive the KPA500 to > full output - you may be able to get somewhere betwen 200 and 300 > watts > out of it. > > 73, > Don W3FPR > __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] 100 Watts or 500 Watts
Bill, It is not an Elecraft choice. While you could do that as an individual, commercial products (sold in the US) must meet the FCC requirement of a 15 dB maximum gain That limits the maximum power gain to a factor of 31.62 - 10 watts in gives 316.2 watts (at the most) output. 73, Don W3FPR On 12/20/2010 3:23 PM, able2...@aol.com wrote: > Why wouldn't Elecraft design the KPA500 to be driven to its rated output by a > K3/10 ? > > Bill K3UJ > > > > > > > -Original Message- > From: Don Wilhelm > Subject: Re: [Elecraft] 100 Watts or 500 Watts > > >Frank, > If you think you want 500 watts out, you will have to install the KPA3 > 100 watts) anyway. The K3/10 will not be able to drive the KPA500 to > ull output - you may be able to get somewhere betwen 200 and 300 watts > ut of it. > 73, > on W3FPR > > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] 100 Watts or 500 Watts
Why wouldn't Elecraft design the KPA500 to be driven to its rated output by a K3/10 ? Bill K3UJ -Original Message- From: Don Wilhelm Subject: Re: [Elecraft] 100 Watts or 500 Watts Frank, If you think you want 500 watts out, you will have to install the KPA3 100 watts) anyway. The K3/10 will not be able to drive the KPA500 to ull output - you may be able to get somewhere betwen 200 and 300 watts ut of it. 73, on W3FPR __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] 100 Watts or 500 Watts
Frank, If you think you want 500 watts out, you will have to install the KPA3 (100 watts) anyway. The K3/10 will not be able to drive the KPA500 to full output - you may be able to get somewhere betwen 200 and 300 watts out of it. 73, Don W3FPR On 12/20/2010 1:39 PM, Frank MacDonell wrote: > I own a K3/10 with ATU and would like to upgrade power. The question > is do I go with the 100w PA option or wait for the KPA500. Any and all > comments are most welcome. Thanks in advance and Merry Christmas to > all. > __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
[Elecraft] 100 Watts or 500 Watts
I own a K3/10 with ATU and would like to upgrade power. The question is do I go with the 100w PA option or wait for the KPA500. Any and all comments are most welcome. Thanks in advance and Merry Christmas to all. -- Frank KD8FIP __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
