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I understand a chap in the UK has made the seller aware of the utter poor quality of this linear
I wanted to know who built it with two plate chokes in series??
At least they knew to place them at right angles.... but why so much L?? ?
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hurry and see it before someone buys it ?? as my Scottish friend would say "Perish the thought!"
Reid? W6MTF
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From the looks of it, it appears the amp is only for 11 meters. With the small inductors and the caps missing plates, I bet it was designed with CB in mind. I also do not think that it has ever been fired up. Those chokes would have so many self-resonances they would be black. The markings on the front panel is an attempt to make it look legit. 73 – Mike ? Mike B. Feher, N4FS 89 Arnold Blvd. Howell NJ 07731 908-902-3831 ?
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From: [email protected] < [email protected]> On Behalf Of Brandon DX via groups.io Sent: Wednesday, October 30, 2024 11:15 PM To: [email protected]Subject: [ham-amplifiers] the WORST ham built amplifier? ? I understand a chap in the UK has made the seller aware of the utter poor quality of this linear I wanted to know who built it with two plate chokes in series?? At least they knew to place them at right angles.... but why so much L?? ? hurry and see it before someone buys it ?? as my Scottish friend would say "Perish the thought!"
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That amp uses a PI-L output for the 11m tank.? ? The vertical plate choke has the B+ fed to the top of it....and existing the bottom.?
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56 pounds sterling = $72.00? US dollars.? ?You could get it for way less than that.? ?The pair of tubes, sockets, blower, 2 x caps is probably worth $50.00? ? ?Good for some parts if the tubes are any good.?
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Two ?plate RF chokes in series ?were used in the homebrew 4-1000A amplifier that I designed and built in the early 80's and is still in reliable service at my 4X4NJ station. At the time, I didn't have convenient access to any references that detailed the construction of a suitable single plate choke. And I felt that even given the lacking information, it would have been unlikely that I would be able to find the proper coil form for the choke. ?The need for a second choke arose because of the undesirable frequency of the series resonance of the first choke. Instead of cut-and-try attempts to get a single choke to work properly, it was much simpler just to add a second choke in series with the first choke.? Since the total impedance is the sum of the impedances of both chokes, and the second choke series resonant frequency was far away from the resonant frequency of the first choke, the problem was solved.? An additional advantage was the overall increased impedance of the two choke combination on most frequencies. The obvious potential disadvantage was the increased space for two chokes, but this was not a problem (in this project) with plenty of space for a second choke. 73, Riki Kline K7NJ/4X4NJ -- Riki, K7NJ
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I was wondering if multiple plate chokes would take care of the series resonance problems across HF spectrum....and it sounds like this is is the case..
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Eric
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WB6TIX
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Continuing on the subj of plate chokes, since that is what the worst linear pic triggered me on
And incidentally its customary to tie the plate(s) of the tube to the top of the rfc, with the top cover pacing capacitance to the choke (as well as the plate tank ckt) the amp in question has the bottom of the first rfc going to the plates and the top is tied to the second rfc.? Certainly not the way I would have done it!
When I was tasked with rebuilding W6CCP's Henry ?K I really spent a lot of time with the upper deck, as well as a new plate transformer to get rid of the resonant HV choke in the plate supply. I never liked those, this had an oil filled cap that was DOA. And iron laminated choke with a high resistance (what were those swinging chokes?). A new transformer went in and I had to reinforce the chassis to keep it from bending.
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I used ?K because I'm not sure it was originally built as a ham linear, at least according to Seymour who bought it from someone known to have modded Henry stuff intended for industrial applications. See pic attached for someone who might have more experience than I.? ??
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I first made the 80-10 choke with no series resonance on any ham freqs. I had access to a lathe and spent more time making chokes than I care to remember, I think it was my third attempt when I was happy.? It's totally experimental trying to come up with a rfc that has no series resonance where you intend to operate. Even with a lot of fancy test equipment, the first choke you make is a stab in the dark as they say.??
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After my "good" 80-10m rfc was installed without one for 160M, the amp was tested on 75M one night. Besides a local on sked the first "dx" I worked was a VE3 who happened to say he was also running a 3 by 3.? This was after midnight his time as I remember.?
With that accomplished I tackled 160M. I simply wound a second choke arbitrarily (actually it was one I intended to use for a 6M amp) and placed it in series with a small vac relay to short it out.? I found that was necessary because the 2 chokes in series created a series resonance (I think it was near 15M), clearly they interacted. I still have my notes somewhere because I thought if I ever wanted to make another plate choke I follow what I learned from this experience. Sorry I won't give away my secrets tho!
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Ultimately the plate transformer I used was tad bit on the low side but with 5.6kVdc on the tube at 1.2A on 160M it delivered 3800W with 125W in at an efficiency of 56%.? I would liked to have 6500V, if I did the   output and efficiency would have improved for the same drive or less.? So what I am saying is if you really want a 160-10M QRO amp you are going to need to use series rfc's and my experience was one had to be shorted out on bands other than 160 to preserve the resonance in the main rfc.? ?as they say, of course YMMV.
Reid? W6MTF?
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well, it should be obvious some CB'er tried to make it work on 27megs. I note one inductor looks un connected on the loading side as if someone had it configured as a Pi-L at some point?
Meanwhile I didn't check the hit counter on eBay when I was first told this thing was FS.
But check it out now!?
Its showing 196 views!!!? ?I wonder how many of those were from from thjs forum???
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Reid
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Reid, can you safely put 6500 vdc (loaded) on a 3x3 tube ?? ?What about IMD with that voltage ?? ?Most folks are getting 68% eff on the lower bands (160-30m)....with 4800-5500 vdc loaded...and a little less on 20-17-15m.? ?Typ they are driven with a 200 watt xcvr in most cases, but not always.?
That RF deck appears to be a Henry RF generator, modified with a roller coil and 2 x vac caps.?
The 3x3 will typ hi-pot test to 20 kv (anode to grid).?
Do you remember what was used for the tuned input ?? ?Was it a mess of bandswitched PI networks, or direct driven ???
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I guess efficiency and IMD will improve with 6500V at the anode, but 10m will be difficult to tune and on 160m the Gates inductor might be too small in inductance.
Mine is run at 4800V, 10-160m on any frequency, no tuned input.
Second RF choke is shorted out from 40m down while another short across the roller inductor is taken out by deenergizing another relay.
Yes, W6CCPs rack was probably a Henry 3000D generator, perhaps the OEM version by Perkin Elmer.
I modified many of them, most to mono band amps, three out of 10 to all band.
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73
Peter, DJ7WW
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-----Original-Nachricht-----
Betreff: Re: [ham-amplifiers] the WORST ham built amplifier?
Datum: 2024-11-06T17:49:25+0100
Von: "Jim VE7RF" <jim.thom@...>
An: "[email protected]" <[email protected]>
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Reid, can you safely put 6500 vdc (loaded) on a 3x3 tube ?? ?What about IMD with that voltage ?? ?Most folks are getting 68% eff on the lower bands (160-30m)....with 4800-5500 vdc loaded...and a little less on 20-17-15m.? ?Typ they are driven with a 200 watt xcvr in most cases, but not always.?
That RF deck appears to be a Henry RF generator, modified with a roller coil and 2 x vac caps.?
The 3x3 will typ hi-pot test to 20 kv (anode to grid).?
Do you remember what was used for the tuned input ?? ?Was it a mess of bandswitched PI networks, or direct driven ???
? ?
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Jim, I snapped a pic of the bandswitched input network.
You can see the 40M toroid has been overheated, I recall that was the band W6CCP used it on.?
Note the red paint applied to the mica cap tuning screws.?
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I wasn't in So Cal when W6BWG completely redesigned it so I don't have any pics of the new version but I'm certain it looked 100% professional.
I believe he used relays instead of the long leads going to the wafer switch as shown.?
He said an ex-Henry Radio employee did the original Kluge for Seymour.? yeah, a 3K would be the chassis.? I had to move the counter dial drive out front on the panel an inch or more to get the roller coil into the chassis. Kintronics supplied the coil. By some stroke of luck it just worked at 1.8+/-MHz with the coil almost end-stopped (like a 1/4 turn left on the tuning dial).? ?
I was told that after CCP died the linear was bought by someone and moved to FL. I seem to remember a K5 call??
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As for the plate voltage, 6500 is as high as I would go and mind you I am not doing tube calculating any longer but the drive requirements would be less and I don't have any IMD data on the 3000A7 but I did at one time have a binder full of everything you can imagine on tube calculations on this and lots of other tubes with some actual data taken when  I had access to the Advance Products Lab.? ? When CPI eliminated my position I was acting marketing manager of the ailing Eimac business and management wouldn't allow me to log onto my PC that fateful morning.? I went to HR and got my "walking papers" and they placed everything out of my file cabinet in a dumpster.??
73,? Reid? W6MTF
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Seymour probably? used the amp also on 20m where I met him most on the long path.
We were talking about using the same tube in our amps.
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73
Peter, DJ7WW
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-----Original-Nachricht-----
Betreff: Re: [ham-amplifiers] the WORST ham built amplifier?
Datum: 2024-11-07T20:13:07+0100
Von: "Brandon DX via groups.io" <rfburnz@...>
An: "[email protected]" <[email protected]>
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Jim, I snapped a pic of the bandswitched input network.
You can see the 40M toroid has been overheated, I recall that was the band W6CCP used it on.?
Note the red paint applied to the mica cap tuning screws.?
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I only ever heard Seymour on 20m.? He was a real character.? ?He was stupid loud here, with his yagi pointed my way.
Those mile long leads will screw up the coil values a bunch.... on those depicted tuned inputs.
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56% eff isn't good at all.? ?You shoulda been able to get 68% eff on? 160-40m.? ?I'm assuming? your plate current meter, HV meter, wattmeter are all? calibrated ??
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He had a big signal and a good location. At the better part of the sunspot cycle you could hear Seymour more on 15 meters he had huge long boom Yagi on 15 meters combined with his location? and he was the only signal on the band at 5/9+30Db.? ?I could routinely hear? his signal and echo on both long and short path. Even if you removed the power from? his equation he was still loud and had a terrain advantage that nobody else could match. It was amusing listening to the idiots complaining about his splatter when he overloaded their receivers when he had none. They were all using lousy receivers and his IMD was very good, one of the cleanest signals on the band.
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One thing that was interesting was that Seymour used a Beverage on the higher bands to listen to very weak stations. He could hear stations that Dale, Ray W6ZR and many others could not hear. His signal became worst when he decided to use a Quagi that eventually fell down. He ran a dipole on 20 meters for a short period of time and consistently his signal was better than the majority with this dipole up high. There was only one station louder than him who was located on the same mountain, I think his call was W6BH that had a remote? super station right on the peak of the mountain with pretuned amplifiers. He was not on very often however you would take note when someone was 10Db stronger than Seymour. I used to use a Rohde ESH2 calibrated receiver to give comparisons and front to back reports when they fighting to be the loudest signal on the block.
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Dale K6UA had a similar advantage firing over the pacific with sloping terrain. Terrain enhanced hams are always the real big guns.
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Now its all? the big guns have gone silent from the West Coast, theres no regular rag chewers or antenna tests on the bands these days. Mel W6FDR is about the only big signal that you hear regularly. The good old days? of big guns are gone. The End Fed? antenna from the packet crowd that you cant hear.
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Henry
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On 11/11/2024 6:26 PM, tardivat via groups.io wrote: I think his call was W6BH that had a remote? super station right on
the peak of the mountain with pretuned amplifiers. Was W6BH around Anza in SoCal?? If so, I believe that property got bought by WA6TQT, who has a massive antler farm with many stacked yagis on those several hills (in addition to his home-spun "golf course" 8-). He told me the antler farm was built by the previous owner, whose call I can't remember but W6BH sounds familiar, because I had never heard of this so-called "big gun" before (if he was primarily a SSBer, then no wonder!). There are a bunch of SDDXC and SCCC contesters, such as N5ZO, NE6I, K6JO, and others, who run contests from his station, mostly remotely. He only has two or three operating positions for all those huge stacked antlers... and some of them are really large. I didn't see any equipment that could have been W6BH's... absolutely no tubes anywhere other than perhaps an ultra-modern final or two, like maybe an Acom... when I visited TQT several years back. I'm not aware of any other large contesting stations in the SoCal area any longer other than a very few singletons. Steve, K0XP
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Yup: WA6TQT is now the old W6BH Radio Ranch. See his qrz.com
profile, illustrating some of his 195-foot rotating towers plus a
nice photo of Seymour, W6CCP.
Steve, K0XP
On 11/11/2024 7:51 PM, Steve wrote:
On
11/11/2024 6:26 PM, tardivat via groups.io wrote:
I think his call was W6BH that had a
remote? super station right on
the peak of the mountain with pretuned amplifiers.
Was W6BH around Anza in SoCal?? If so, I believe that property got
bought by WA6TQT, who has a massive antler farm with many stacked
yagis
on those several hills (in addition to his home-spun "golf course"
8-).
He told me the antler farm was built by the previous owner, whose
call I
can't remember but W6BH sounds familiar, because I had never heard
of
this so-called "big gun" before (if he was primarily a SSBer, then
no
wonder!). There are a bunch of SDDXC and SCCC contesters, such as
N5ZO,
NE6I, K6JO, and others, who run contests from his station, mostly
remotely. He only has two or three operating positions for all
those
huge stacked antlers... and some of them are really large. I
didn't see
any equipment that could have been W6BH's... absolutely no tubes
anywhere other than perhaps an ultra-modern final or two, like
maybe an
Acom... when I visited TQT several years back.
I'm not aware of any other large contesting stations in the SoCal
area
any longer other than a very few singletons.
Steve, K0XP
--
See my QRZ.com page at
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There were some serious tube amplifiers at the location that were removed and sold when he became SK.? ?As? he explained it was one RF Rack with a monobander that was pre-tuned with vacuums in a set and forget configuration. They had no turn counters and the vacuum? caps stuck through the front panel.? Apparently it was designed a one of the best RF Engineers on the best coast.
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Once? I worked him and 20 meters was totally dead, he was the only SSB station on the band peaking 40db over S9 on the Rohde receiver. He definitely could radiate a signal.
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He was very wealthy apparently? and had big bucks like Gordon Marshall whose call I now forget.
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Whoever has that location would be very happy. I was told by Seymour that the station was above him and higher up? on the mountain in Anza.?
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Theres lots of big stations around that are simply not very active which seems like a waste like all that great hardware. Seymour got his moneys worth on his station he was so active. Everyone listens nobody calls CQ like when ham radio and calling CQ was in everyone's blood even if they had a wire.
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Henry
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On Tue, Nov 12, 2024 at 08:15 AM, <tardivat@...> wrote:
<There were some serious tube amplifiers at the location that were removed and sold when he became SK.? ?As? he explained it was one RF Rack with a monobander that was pre-tuned with vacuums in a set and forget <configuration. They had no turn counters and the vacuum? caps stuck through the front panel.? Apparently it was designed a one of the best RF Engineers on the best coast.
Ok, mystery finally solved.? That amplifier you are referring to was offered to me, but I turned it down,? since I have 7 amps already.? ?I knew it came from a SK contester in Southern California, but never did find out who the contester was.? If you go to the home page on this group,? you can see the pix of the amp.? ? It's made for 80-40-20-15-10m,? 5 bands.? ?Each band has it's own vac tune and vac load cap...and no turns counters used.? ?It was just the bell housings sticking out the front panel, with a knob on each shaft.? ? The 5/8" tubing tank coil is mounted vertical.? A mess of new Gigavac? G9? DPDT ceramic vac relays were used to switch bands.? The idea of course, was for a say SSB contest, all 10 x vac caps were tweaked for the middle of the? SSB contests? freqs.....and ditto for a CW contests.? After that, it was just instant band change, with a rotary switch activated the mess of vac relays...or switched by the xcvr.? ? ?Drawback is it can only be used on one band only at a time.....so it's really only good for a MS contest, or perhaps in the case of a MM? contest, where each station has a smaller amp..... and one of em needs more oomph, the big amp was switched inline. It used an Eimac? 3CX-10,000A7 in GG.? I have no clue what they used for an IPA? to drive it with.? Probably an Alpha 87 or similar.? ? I never saw the tuned input setup they used....but I'm assuming? it too was also relay switched monoband PI tuned inputs...which would have to be pretty robust to handle 1500 watts of drive.? Perhaps the current owner can post some more pix of it.? I believe I still have some pix of it..... on? my old laptop somewhere.? It was a unique design, never seen one like that before or since.?
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On 11/13/2024 8:15 AM, Jim VE7RF via groups.io wrote: It used an Eimac? 3CX-10,000A7 in GG.? I have no clue what they used
for an IPA? to drive it with.? Probably an Alpha 87 or similar. SoCal Edison must have been very curious about that high but extremely erratic power consumption 8-) I wonder whether he used 3-phase... If so, he must have been the only 3-phase customer for miles around. I believe the next closest such customer would have been an Indian casino about 10 or 15 miles away. Steve, K0XP
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On Thu, Nov 14, 2024 at 05:42 AM, Steve wrote:
<SoCal Edison must have been very curious about that high but extremely
<erratic power consumption 8-) I wonder whether he used 3-phase... If so,
<he must have been the only 3-phase customer for miles around. I believe
<the next closest such customer would have been an Indian casino about 10
<or 15 miles away.
The tube is rated for 8 kv loaded at 5 amps. Run at the max of 40 kw input =? 27 kw pep out..... = 173 amps? when run on 60 hz? single phase.? Typ, that tube is run at just 17 kw out...... =? 25 kw input =? 108 amps? when run on 60 hz single phase.? ?Average current on SSB is just 54 amps.? To do it right,? on 60 hz? single phase,? you get em to install? 400 amp service. ...or more,? or? 2 x 400 amp drop lines into the house, with 2 x 400 amp panels.? The other method with? 400 amp service is? to use a 400 amp meter base, with 2 x 200 amp lines paralleled? from the meter base output.... with each line feeding it's own 200 amp panel.? On my own 200 amp panel,? I can get 2 pole breakers? from 15 amp... up to a max of 135 amp.? I just bought a 2 pole, 100 amp breaker, since I have loads of spare slots on the panel.? ? Previously,? I had installed a 100 amp 2 x pole breaker ...to feed my 100 amp subpanel....which in turn feeds the 4 x L4B's, misc stuff in the shop, and 2 x xcvrs,? rack gear, heat etc.? ?
? ? I use the 'BQL' type breakers in my 200 amp panel.?
So no, you don't need? 3 phase power to run big amps.? 3 phase, like 208/120 is stupid expensive to install.? And you pay extra for the privilege of having it.? 3 phase does offer a lot of advantages though.? IE: the ripple is only 5.2%? on the raw DC? coming from the 6 x leg rectifier assy..... vs? 67% for a FWB? run on 60 hz single phase.? IE: on 3 phase, most of the filtering is already done for you.? ?Ripple freq on single phase is 2F, or 120 hz, if using 60 hz......... and? 6F, or? 360 hz, if using? ?3 phase? 60 hz.?
Perhaps Dino, etc, can post a few more/ better pix of that 3x10 amp...the front panel view of it is superb.?
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Brandon DX
