[Johnson] Richard Measures

[Richard Peterson]

I will throw in the towel about Richard Measures -- I know he has his 
following. However, engineers are not among them, to my knowledge.

If you stop and consider what a parastic oscillation is, you will understand 
that it is cured by bringing its frequency down to the frequency where the 
tube is self neutralized. The parastic is then killed (suppressed) by 
loading it with resistance. That's a fact. Using Nichrome wire according to 
Measure's voodoo concepts a very strange approach, to say the least. Rather, 
the use of a parallel tuned circuit with decent copper wire is a much more 
sound approach.

Now, that said, it is entirely reasonable that a parallel turned circuit 
using Nichrome wire will work, PROVIDING the parallel tuned circuit with the 
Nichrome wire just happens to lower the freqency of the parastic to a better 
point where the existing circuit can deal with it. There are lots of 
variables. But it is the luck of the draw, it is not sound science, and it 
is not the best way. And it has nothing to to with Nichrome wire. But if it 
works for some hams -- Great! I am sincere about that. And Mr. Measures has 
made some sales, too. It's hard to make a dollar, and I admire his hard 
work.

However, I am puzzled by the report in this thread that parasitics had 
burned up a band switch. That's hard to understand -- unless there is 
another problem occuring, or the switch were rotated with RF on it .. or 
maybe even if the rig were being tuned into a reactive load. Amplifiers 
prefer 50 ohms j0, and I've run into hams loading their finals into all 
sorts of really wacky loads, which causes a real wreck in the final. To that 
end, for the folks who are reporting success with the Measures parasitics 
kits, I would be curious to know what the frequency of the parastic was 
before the Measures Nichrome modification, and afterward. That would be 
really useful information.

By the way, Mr. Measures earned the wrath of Eimac (and I don't blame them) 
when he alleged that Eimac tubes had internal parastics. Excuse me? That is 
ridiculous. Parasitics are caused by external elements, not internal. 
Period.  And it embarassed the heck out of QST.And it should have embarassed 
them.

I'm fortunate to have a friend who is an electrical engineer who was so 
incredulous by the Measures views on parasitics that he even called Mr. 
Measures on the phone and reprimanded him for foisting that stuff on the 
amateur radio community.

In truth, Measures has written some good stuff. But he has also written some 
bad stuff, and his understanding of parasitics is questionable. And I know 
of rigs that were really toasted when some Richard Measures modifications 
were installed. And yet, we have here in this thread some testimony that it 
worked. That reinforces my belief that some of his improvements DO work, but 
(like I said ) they work by the luck of the draw. But what works, works!

I have always wondered if these rigs with the Measures mods really are 
stable -- if they are completely parasitic free. Maybe yes, maybe no. Not a 
lot of hams know how to run a rig through its paces to see if it has 
parasitics.

But, again, I have no desire to debate this author's view of the world, nor 
to anger those who have had luck with his approach -- except to say I am 
troubled by his views on parasitics.

I will let the matter drop.

Thanks.

Richard, WB5NEN

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