Discussion in 'Amateur Radio Amplifiers' started by N3JBH, Apr 20, 2012.
That's Mr. Rauch
I guess I need to read between the lines ,
Rich & G6K
Isn't that lower Q you guys were talking about ?
Seems to me having a technical discussion , we should leave out anything even closely resembling ,
" Bizarre. Maybe it really does have voodoo properties like Rauch said? "
To me , trying to learn about this , it just confuses the discussion ?
" Just the facts mam "
The voodoo comment was a joke. In Rauch-World, Ni-Cr conductors have the opposite RF skin effect that all other conductors in this universe have.
Facts about VHF suppressors:
No matter how expertly they are designed, all MF/HF amplifiers have a potentially problematic VHF parasitic resonance in their anode circuitry. This resonance can easily be found by coupling a dipmeter to the DC blocker cap. .
A VHF suppressor's purpose is Not to suppress or absorb bursts of VHF energy, it is to reduce VHF amplification to the point that the amplifier tube's C-feedback can not sustain VHF oscillation. A suppressor does this by decreasing the VHF-RL presented to the anode of the amplifier tube. In order to see how it does this, one must find the suppressor's admittance, Y, at the anode's parasitic resonance frequency and convert Y to to the parallel equivalent Z.
• March, 1989 QST, page 7, 'Finding Impedance by Solving for Admittance'. .® The American Radio Relay League, Inc.
The less VHF Q a suppressor has the lower the VHF-RL presented to the anode and the lower the VHF amplification. The hat-trick is to design a VHF suppressor that will not disintegrate at 28MHz which has a low enough VHF-Q to do the job.
Thanks Rich , there is kind of a multi point issue with technical discussions , in all venues .
For those that know something about the subject , the extra / added parts jokes , arguing etc. make it difficult at best , at least for me to try to learn .
When I see 2 or more in a thread start to argue / fight over understanding or worse personality issues what ever .
To me it makes sense to debate perspectives of a subject to fill in other aspect of the subject .
And even when I see some heat get into the debate , if it stays on subject , then I can still bits & peaces out , with the hope of actually having an understanding enough to work on the gear in question .
When things get to the point of personal attacks , it seems the way to deal with that is to just go on as if it wasn't there , that rarely happens , especially on a forum , with the lack of of other communications , body language etc. , in person communication helps to keep from interpreting something that may not have been intended , then things really go off the deep end .
Much my comments here ,
in a technical debate, the person who plays the Ad-Hominem Card is usually the person purveying specious technical arguments. Unfortunately, people with much charisma can convince semi-educated groupie-type people of almost anything to support their position in a debate. Example herein: Ni-Cr conductors have the reverse RF skin effect that Cu conductors have -- so Ni-Cr conductors supposedly have dire consequences when used in VHF suppressors.
On this we agree. Personal / ad hominem attack is too often a ploy by the person who is losing the debate in order to create a virtual stalemate - which he sees as preferable to an outright loss - especially in the eyes of his treasured groupies.
The reason that I publish my phone # is so that anyone who has questions or comments about a response of mine they are reading at the time can talk to me about it now. If I happen to be out when you call, leave a msg and I will return the call when I return.
Well the amp I traded for [ Yaesu FL-2100B ] in non-operating condition and was not working for the guy I traded for it , had not finished his repairs , is now working .
Now to figure out what mods , repairs etc. had done to it .
My plan is to sell after it is in good operating condition , next to checkout the caps .
I bought a Blue ESR meter kit .
But what I am keeping an eye out for is something like a 80B , want to be able to work most HF bands and I like the idea of using about 600watts on a high power amp and just cruising , but looking for discounted dead amps , because of not being able to afford turn-key amps .
And the fun part of figuring out how to fix
Rich your simply amazing. I still am mystified that if some,most or all Amplifier manufactures got the suppressor stuff wrong. Why you have not became the provider or at least consultant to them and corrected there design's. And your groupie crap getting old too. Because a lot of folk's can see through your crap does this make them a groupie? In my case it is not just Tom i like to pay attention to there many on the various web sites i listen to. Funny though all the different folk's i listen to that have stellar reputations think your fruitier then a king size box of Fruit Loops ..... Jeff
Come on Jeff, be nice or else the moderators will throw you out of the sand box.
Yea Lou you're right... Besides i know whom the real pro's are. Why you think i listen to you J/K
Not all amplifier mfgs got it wrong. Hughes used resistive conductors in their 100kw HF amplifier before I wrote the series of articles on parasites for QST. and Art Collins reportedly used one in the 30S-1, (W6HW), a marine-band 1000w amp mfg in the State of Washington uses resistance-wire. Any electronics engineer who can do Y to Z transformations can see why a suppressor's VHF Q controls VHF amplification - which is the key to VHF-stabilization.
The only thing that using resistance-wire for a suppressor buys is that for a given VHF-Q it reduces the 28MHz dissipative burden on R-supp.
If you would like to see an example of groupie crap, I can send you the complete 1MB text of the Grate Parasitics Debate. Tom's groupies were like a seething pack of wild and crazy lap-dogs. Fortunately, before the debate started a friend on Manhatten Island warned me how his lap-dogs operate during a debate and advice on how to deal with their yipping and nipping. It pretty much worked.
Anybody who sees through my crap is somewhat unlikely to know that Y = admittance, much less be able to find parallel-equivalent ohms through finding admittance in Siemens. .
ref: March, 1989 QST, page 7, 'Finding Impedance by Solving for Admittance'. .® The American Radio Relay League, Inc.
Lou Pasteur, the Wright bros., and Rudy Diesel ran into pretty much the same thing
So Jeff, do you believe that Ni-Cr has reverse RF skin effect? Also, can you find Z by solving for Y? tnx