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Re: Which is the best 4-1000 2 holer or the GU84B amp
Robert B. Bonner
What bites is when the manufacturer purposely keeps it out of stock to make it look like it is a good thing and drive the price up.
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BOB DD -----Original Message-----
From: ham_amplifiers@... [mailto:ham_amplifiers@...] On Behalf Of Peter Voelpel Sent: Wednesday, January 17, 2007 5:39 PM To: ham_amplifiers@... Subject: RE: [ham_amplifiers] Re: Which is the best 4-1000 2 holer or the GU84B amp A reliable and not too expensive solution might be this version of 3CX6000A7 by Svetlana: "Better mechanical rigidity and long lasting concentricity of the filament is obtained from the improved mesh filament design contributing to a longer life. Flexible leads connect to the filament terminals and a flange is connected to the grid. The flange provides a convenient way to mount the tube." Product ID: SKU15665 Price: €594.94 including VAT 19% (€94.99) [plus shipping] Unfortunately not in stock at the moment 73 Peter ________________________________ From: ham_amplifiers@... [mailto:ham_amplifiers@...] On Behalf Of Robert B. Bonner The trend is for cheap reliable power. Yahoo! Groups Links |
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Re: Which is the best 4-1000 2 holer or the GU84B amp
Robert B. Bonner
Yeah Peter,
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For some reason, the good stuff is never in stock. BOB -----Original Message-----
From: ham_amplifiers@... [mailto:ham_amplifiers@...] On Behalf Of Peter Voelpel Sent: Wednesday, January 17, 2007 5:39 PM To: ham_amplifiers@... Subject: RE: [ham_amplifiers] Re: Which is the best 4-1000 2 holer or the GU84B amp A reliable and not too expensive solution might be this version of 3CX6000A7 by Svetlana: "Better mechanical rigidity and long lasting concentricity of the filament is obtained from the improved mesh filament design contributing to a longer life. Flexible leads connect to the filament terminals and a flange is connected to the grid. The flange provides a convenient way to mount the tube." Product ID: SKU15665 Price: €594.94 including VAT 19% (€94.99) [plus shipping] Unfortunately not in stock at the moment 73 Peter ________________________________ From: ham_amplifiers@... [mailto:ham_amplifiers@...] On Behalf Of Robert B. Bonner The trend is for cheap reliable power. Yahoo! Groups Links |
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Re: Which is the best 4-1000 2 holer or the GU84B amp
Peter Voelpel
A reliable and not too expensive solution might be this version of 3CX6000A7 by Svetlana:
"Better mechanical rigidity and long lasting concentricity of the filament is obtained from the improved mesh filament design contributing to a longer life. Flexible leads connect to the filament terminals and a flange is connected to the grid. The flange provides a convenient way to mount the tube." Product ID: SKU15665 Price: €594.94 including VAT 19% (€94.99) [plus shipping] Unfortunately not in stock at the moment 73 Peter ________________________________ From: ham_amplifiers@... [mailto:ham_amplifiers@...] On Behalf Of Robert B. Bonner The trend is for cheap reliable power. |
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Re: Which is the best 4-1000 2 holer or the GU84B amp
"Robert B. Bonner
The trend is for cheap reliable power. A couple 8877's will make moderate power at medium risk. A couple 3CX1200A7's will make almost as much power with low risk. Their limit to maximum power is its plate dissapation. Too bad Eimac didn't widely release the 1500 dissapation (YU whatever) version. It sounds like a great tube. No matter what a guy does. Whether it is a 6L6, 811A or an X2159 if you run it consurvatively with safeguards it will last forever. Push it and watch it go Bye-Bye. BOB DD
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Sent From Mobile Device -----Original Message-----
From: "hbmandel" <ka1xo@...> Date: Wed, 17 Jan 2007 22:52:43 To:ham_amplifiers@... Subject: [ham_amplifiers] Re: Which is the best 4-1000 2 holer or the GU84B amp [snip] Seems to be alot of hams going to the GU84B tubes for their Big[snip] I agree. Here's the breakdown: The 8877 tube is hellishly expensive and has a filament that is extremely sensitive to shortened life because of a few hundredths of an overvoltage. Additionally, its 25 watt Grid Dissipation rating makes it vulnerable if not sutably protected, to damage from mistuning and arcs. The 4-1000A being a Tetrode, is happiest being Grid-Driven, but few amateurs have the inclination to design and experiment with driving and neutralization techniques, so many of these tubes end up Grounded Grid at a miserable efficiency. Additionally, the 4-1000A, with a 6KV at 1 Amp anode requirement needs a power supply to suit, and while transformers and diodes are plentiful, adequate filter caps are not, and those that are available are hellishly expensive once the array is gathered to afford low ripple at maximum amperage. Hal Mandel W4HBM Yahoo! Groups Links |
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Re: Which is the best 4-1000 2 holer or the GU84B amp
hbmandel
[snip]
Seems to be alot of hams going to the GU84B tubes for their Big[snip] I agree. Here's the breakdown: The 8877 tube is hellishly expensive and has a filament that is extremely sensitive to shortened life because of a few hundredths of an overvoltage. Additionally, its 25 watt Grid Dissipation rating makes it vulnerable if not sutably protected, to damage from mistuning and arcs. The 4-1000A being a Tetrode, is happiest being Grid-Driven, but few amateurs have the inclination to design and experiment with driving and neutralization techniques, so many of these tubes end up Grounded Grid at a miserable efficiency. Additionally, the 4-1000A, with a 6KV at 1 Amp anode requirement needs a power supply to suit, and while transformers and diodes are plentiful, adequate filter caps are not, and those that are available are hellishly expensive once the array is gathered to afford low ripple at maximum amperage. Hal Mandel W4HBM |
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Re: New file uploaded to ham_amplifiers
pentalab
--- In ham_amplifiers@..., FRANCIS CARCIA <carcia@...>
wrote: negative feedback to quad 811s ### The file I uploaded has nothing to do with 811's. ### W5CUL and myself wrote it last spring.[6 x months to write and research it, and test everything] Although not directly related to Amps.... not too many have seen it. And it was thought it may well be interesting reading to some yaesu MK-V owner's. At least it's squeaky clean after I got through with it. ### Hopefully my next PDF file depicting all the 3x6 schematics will be as professional looking as the MK-V document. Stay tuned... it's a time consuming, tedious process. Later... Jim VE7RF |
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Re: New file uploaded to ham_amplifiers
FRANCIS CARCIA
Check the old RCA transmitting tube handbook showing how to apply RF negative feedback to quad 811s
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ham_amplifiers@... wrote:
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New file uploaded to ham_amplifiers
Hello,
This email message is a notification to let you know that a file has been uploaded to the Files area of the ham_amplifiers group. File : /mkvmods1_0.pdf Uploaded by : pentalab <jim.thomson@...> Description : Yaesu MK-V ESSB mod document You can access this file at the URL: To learn more about file sharing for your group, please visit: Regards, pentalab <jim.thomson@...> |
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Re: Real Yahoo amp on Ebay...
Randy
1800 Toll Free wrote:
change a couple caps to make the harmonic-o-meter swing farther to the right, and call it 'your' design.Wouldn't that be pronounced a "harmonica-meter" or "monicatometer" or"harmonomominer" on 11M? One day, given some technological strides, with DSP the 11M op will be able to completely remove the original signal, leaving only THD to swing the Harmonc-o-meter. If only the Old Man had known, he'd have designed a wouff hong just for what would happen on what *used to be* our 11M band. 73, Randy KZ4RV |
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Re: Harmonic-o-Meter
pentalab
--- In ham_amplifiers@..., 1800 Toll Free
<TollFree1800@...> wrote: transistor amp (2X2290, Texas Star DX250) and see > 500 watts PEP.these harmonicomoeters.type of switch / solenoid... "Thing won't unkey, but hey, it's doin a(read this as old style headlight dimmer, footboard based) and use it tounkey the thing. Man, I never had a two pill doin a gran before!!!".### why not just use a PEP reading wattmeter ?? Everybody and their dog makes pep boards for the bird/CD wattmeter's. Those depicted on the photo page are entirely HB.... 4 of em.. for all 4 x line sections. ### BTW.... Jay at Array Solutions now makes his new wattmeter with couplers for 3-10-20 kw. They are extremely accurate........ unlike the bird [ 5% on average, 8% on pep] or the Coaxial Dynamics wattmeter's [5% on average, 7% on pep] ### The trbl with both the bird /CD meter's is this... they are ONLY +/- 5% of full scale... ANYWHERE ON THE SCALE !! ### IE: with a 1 kw slug.... and meter indicating say 100 w...... real power could be 50w... and meter is reading 50w too high [100 % error]...... OR.... real power could be 150 w.... and meter is reading 100w.... or 50 W too low. [way off] ### ONLY time u get 5% accuracy is when meter is pegged. IE: 1 kw slug used.... indicates 1000 w. Real power could be 950w or 1050 w. ### Point is this.... anything below full scale.. and accuracy drops like a rock. ... so use the smallest slug u can get away with.. for a given power level. ### The other problem with the bird/CD 7/8" line sections.. AND also the 1 5/8" line sections is this. The 7/8" line sections are use QC connectors.... which have this floozy small diam 1/8" pin on the back end..... meanwhile, their is a 3/8" diam tube running the entire length of the line section... dead center... inside the 7/8" ID tube. Remove the slug... and u can see the 3/8" tube urself. The 3/8" tube will handle GLOBS of RF.... the QC connector's won't. ### On the 1 5/8" line sections..... same deal.... except u need an adaptor plate to use the QC connectors. same deal.... QC connectors have this small 1/8" pin on back end.... embedded in solid teflon cylinder. [same deal on 7/8" line sections] ### 11m ops tell me they can actually melt the teflon... runs out on the table like molten candle wax !! ### U don't have that kind of mickey mouse on the array solutions couplers.... trbl is... they gotta be ordered with one type of connector only..... no big deal.... order em with 7-16 Dins...since nobody is gonna run 15 kw with a SO-239 /Type N anyway. ### The Array solutions wattmeter's hold their 3% accuracy across the spectrum. They are so fast... that just ONE.. "dit" sent at 60 WPM... will cause the digital numerical display to read... "14,250 w" The numerical display will hold it for how long u want... up to 2 seconds. You can do other cool stuff... with a PC... like graph swr across the entire band, just by talking on ssb... and spinning the dial. It will also show u stuff about ur xcvr u don't wanna know... like typ overshoots. ### The Coaxial Dynamics 25 kw slug has each increment at 500 w... but u can easily visualize... and split into 250 w . ## The bird/cd may well have been the standard.... but imo... they have now been well surpassed. The latest software for the array solutions wattmeter's will indicate percentage of modulation for AM broadcast use... or amateur use. Throw in the high swr shut down... it's a total package. Check it out. later... Jim VE7RF
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Re: Harmonic-o-Meter
It's something like this:
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Voltage sampler, 1N series diode detector based 10Kw RMS meters. Then, take the negative feedback off one side of a popular two transistor amp (2X2290, Texas Star DX250) and see > 500 watts PEP. The 350 model (twin 2879s) will show near 1000 watts, PEP on these harmonicomoeters. People actually do this, and put the B+ lead to the amp on some type of switch / solenoid... "Thing won't unkey, but hey, it's doin a thousand!!!!!!.. I put this here foot switch in the positive lead (read this as old style headlight dimmer, footboard based) and use it to unkey the thing. Man, I never had a two pill doin a gran before!!!". Make sense? --Toll_Free On Tue, 16 Jan 2007 10:48:30 -0800, Harold Mandel <ka1xo@...> wrote:
[snip] --
*Ratings are for transistors, tubes have guidelines* |
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Re: Harmonic-o-Meter
FRANCIS CARCIA
like a dispersive and compressive delay line in a radar system. What a cool idea run square wave and reconstruct. Class I amplifier (for idiot mode)
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Harold Mandel wrote:
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Harmonic-o-Meter
Harold Mandel
[snip]
Take an amp, change a couple caps to make the harmonic-o-meter swing farther to the right, and call it 'your' design. [snip] The snippet above implies a device to measure harmonic content. Where can I get one? If let's say I run across a 25KW (Bird Watts) amp, and I can get one of these harmonicometers, will it SUM the energy in, let's say the First through Thirteenth harmonic so I can show it to my 11M eyeball-QSO drinking buddies as maybe being 50 or 60 KW? Oooooo, the possibilities here for more "commercial" sales. Hal 6L6GB |
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Re: Real Yahoo amp on Ebay...
I wonder if Sonny was the last person to work on it, so they are claiming it is a "sonny" built box.
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That's the latest trend of 11 meter 'techs'... Take an amp built by someone else, change a couple caps to make the harmonic-o-meter swing farther to the right, and call it 'your' design. Sonny built some nice stuff... He mentored under Dennis O for quite some time. Last I heard, he was more into the strip club and biker bar business than he was into 11 meter stuff. Most of his regular customers where looking elsewhere for repairs and new stuff. --Toll_Free On Tue, 16 Jan 2007 02:39:02 -0800, craxd <craxd@...> wrote:
--- In ham_amplifiers@..., "Mike Sawyer" <w3slk@...> --
*Ratings are for transistors, tubes have guidelines* |
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Re: hi power mobile
Harold Mandel
¿ªÔÆÌåÓýThe cost of inverters that approach a sine wave rises as the quality of the output waveform approaches ¡°linearity.¡± ? It¡¯s the same sort of exercise as the digital photography evolution. ? A single frame of 35mm emulsion (analog) film has trillions of silver particles that can be affected by light. Digital images fill up the electronic CCD chip that in today¡¯s cameras have let¡¯s say 6 mega-pixels to be affected. ? In olden days of digital photography where the CCD pixel count was low, the photograph would eventually display digital artifacts, or little square blocks of contrasting info, these blocks becoming smaller and smaller as the technology progressed towards higher CCD resolutions, but at some point, the little artifacts were still there. ? This is the same phenomenon as a.c. inverter technology. Seen from a distance, the output waveform resembles a sine wave. Getting closer, e.g., dividing the time base into smaller and smaller segments, the little square-wave stepping blocks become apparent. ? As our radio technology improves, our radio¡¯s microprocessor and signal processor departments divide time into smaller and smaller segments. ? This is why the pure analog sine wave remains the best, as the switching transient noise, generated when the voltage waveform ¡°clicks¡± into the next higher or lower segment, produces a transient that more modern radios may not filter. ? As Will says, in the tube days, a vibrator component produced the high voltage a.c., but if you remember those radios, you could hear the vibrator in the receive audio. ? I don¡¯t know if I can afford the type of inverter that would be able to not make artifacts my radios could pick up. ? The bigger computer installations still use Motor-Generator sets where battery power runs rotary alternators, for those brief moments waiting for the emergency alternators connected to diesel engines, kick in. ? Smaller installations using UPS plants have solid state inverters run by the battery, but as the speed of the servers goes up and up, the inverter supplies end up being upgraded to finer and finer pseudosinusoidal waveforms. ? Hal Mandel W4HBM ? From:
ham_amplifiers@... [mailto:ham_amplifiers@...] On Behalf Of FRANCIS CARCIA ? You can get a clean output from a converter if the sample frequency is high enough. I run tube and solid state PDM AM and make clean audio running a 75 KHz. sample frequency. You also need a good filter / integrator after the PDM. My sidebands are a good 75 dB down. Modern aircraft use solid state converters to convert 270 VDC to 400 hz 3 phase 115VAC. This eliminates the constant speed PTO off the motor. gfz
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Re: hi power mobile
FRANCIS CARCIA
You can get a clean output from a converter if the sample frequency is high enough. I run tube and solid state PDM AM and make clean audio running a 75 KHz. sample frequency. You also need a good filter / integrator after the PDM. My sidebands are a good 75 dB down. Modern aircraft use solid state converters to convert 270 VDC to 400 hz 3 phase 115VAC. This eliminates the constant speed PTO off the motor. gfz craxd wrote:
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Re: Real Yahoo amp on Ebay...
craxd
--- In ham_amplifiers@..., "Mike Sawyer" <w3slk@...>
wrote: there is no way that "thing" is going to pump out 36KW. She told him he was notwould be rejected! It don't look like any "real" human being has bid on this yet. If they did, they're a fool. Most CBr's I know have better sense than that. I personally wouldn't give no more that $150 to $200 for it just for parts. I guess she or he thinks that nobody knows where those Tennessee Walkers are made at either. It sure isn't in Michigan like they claim. What makes me wonder is why the one selling it wasn't killed by electrocution as dumb as they sound to be. Mod-U-Lator,Best, Will |
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Re: hi power mobile
craxd
--- In ham_amplifiers@..., "Harold Mandel" <ka1xo@...>
wrote:
Hals correct. An alternator less the rectifier stack produces the best sine wave possible. It is as pure an AC 3 phase current as delivered by the power company. Most inverters produce either a square wave or a modified (quasi- sine) sine wave. The quasi-sine wave is actually a square wave but is in a stair step fashion where the steps would fit within the arc of of 1/2 of a sine wave. The negative cycle is a mirror image of the positive 1/2 cycle. Of course a pure square wave is merely like the on and off function of flipping a switch. The quasi-wave has to have a wave shaping circuit. It supposed to match a sine wave more closely which in turn goes into figuring the power transformers specifications. The transformers form factor is what changes over this. For mobile use, a transformer ran from an alternator or other AC source uses 4.44 for the form factor where a square wave uses 4.0. The form factor is figured from the rms and average values of a sine wave (4 x 1.11 = 4.44). I can't remember what the quasi-square wave uses. The old sweep tube mobile amps used square wave switching supplies with several different transformer schemes. The old automobile radios used this too. The first ones used vibrators, then they switched to solid state square wave inverters. These are not hard to design as the transformer itself is what determines the oscillation frequency. The primary is two 12V windings. The transistor switching windings supply around 3 to 5 vdc to the base of the switching transistors. The secondary is designed like any other. Theoretically, one could get by without a filter C on the output of the bridge rectifier on the secondary since it's a square wave, but that's not a good idea. spinning
There was some 40 Hz used up there somewhere, but I heard the last of it was finally torn out and replaced with 60 Hz. It was an old hydro plant somewhere, maybe Niagra? [mailto:ham_amplifiers@...] On Behalf Of Robert B. Bonnersells massive quantities of product in the USA. I have some of it on my RV.Phase at least 230V alternator the size of a 200 AMP 12V unit.provides solid sine wave power. SO you wont get that from a spinning alternator,so it is electrically making the sine wave in the box.HZ power but really.?[mailto:ham_amplifiers@...] On Behalf Of PA3DUVme a good step further. Best, Will |