John Curl's Blowtorch preamplifier part II

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Hah!! I was doing my - every decade or so -- clean out the storage... getting rid of unused test gear and audio stuff/parts. I found a like new Marantz 20 FM tuner! The ss successor to the 10B and by Marantz statements it was to be better than the tube model 10B. Merry Christmas and Happy New Year to me. :)

And, to all here in DIY-Land !

-Richard Marsh
 
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On second thought -- I think it might be the 20. I'll have to dig deeper. Either one is fine. I can alwasy add a sota rf preamp front end....
charging up the caps now for a re-listen to the sound. Then do the usual cap replacement for old gear.
-RNM

Here's info on how to tell which.
Marantz Model Twenty Tuner Information Center - Marantz Tuners
The FM-only 20 and 20B look identical and, according to our contributor Charles K., the original nameplate is not always a reliable way to know which tuner you have. Here's his explanation of how to tell them apart: "The difference between the units is in the front end. The 20 used the same passive tuned RF/balanced mixer style design as in the 10. The 20B used a new active design with a tuned RF amp stage which got AGC feedback from the IF section. Problem is, the front end is in a stainless steel housing which is a bear to open up to try and tell the difference. You CAN tell by looking at the rectangular IF section enclosure which is the long, rectangular, stainless steel box mounted behind the black cover which houses the RF stage. This box has RCA connectors (with cable) at each end which is signal in and out. On the right-hand side of the box are two feedthrough posts which are + and - 12 volts for power to the IF section. If the tuner is a 20B, it has a single feedthrough post on the left-hand side for the AGC return. There is no post on the left hand side if the tuner is a Model 20. According to the spec sheet, the B version is slightly more sensitive. I've never had the luxury of having both versions side by side so I can't make any subjective comments, but I like the fact that the 20 mirrors the 10 design more closely." Our contributor David Rich confirms Charles's observations: "In the Marantz 18 and 20 no RF stage at all is used and the mixer is passive. That proved to make the sets unusable with indoor antennas, so they added on RF stage in the 19 and 20B (it is the only difference between the tuners)."
 
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"In the Marantz 18 and 20 no RF stage at all is used and the mixer is passive. That proved to make the sets unusable with indoor antennas, so they added on RF stage in the 19 and 20B (it is the only difference between the tuners)."

THX --- It's the 20. Not 20B according to the description.
I stopped using it because it was as sensitive as Dick Chaney. Great for the city dweller.
But, now, I have a large dual gang antenna with low noise RF amps to use it with. I'll try it out tomorrow.... itis turned ON for the next several hours cooking and forming caps.

-Richard Marsh
 
The issue still is, does that carbon isotope have an effect when coating a wire that is useful or even measurable?

Why is that "the issue"? Nobody made that claim. In fact, there have been no testable claims made here about Carbon-13 or any other substance.

John said Mr. Bybee showed him some "new materials that actually change the state of things nearby", but he didn't say what changed, nor how far away, nor how this was supposed to relate to audio electronics. Later he threw in "C13", but he hasn't actually said anything about it. We know that Carbon-13 is not a new material, so I doubt the two statements are related.

If anyone makes a testable claim about C13 (or anything else) I'll be interested, but until then it is clear that C13 does not reduce noise, but rather increases noise quite substantially (at least in this forum).
 
According to Max's chart regarding sugar intake, it seems I am in very calm waters. Of all the items listed there, the only one I regularly use is a glass of orange juice every morning and that's it. I was never hot on sweets anyway, though I am not above eating a piece of cake about once in two months. It's not that I hate sweet stuff, it just doesn't do anything for me.

The only thing I do need sweetened is my coffee, and years ago I switched to artificial sweetener for diabetics.

But if you think that alone will keep you from getting diabetes, think again. I got it despite my lack of use of sugar, despite that I have an almost ideal blood pressure, and in fact have about a pint of blood more than the average guy, which makes me an ideal blood donor, all the more so due to my relatively rare blood type A-. I haven't caught even a decent flu in the last 15 years, a day's worth of sniffing at worst.
 
If anyone makes a testable claim about C13 (or anything else) I'll be interested, but until then it is clear that C13 does not reduce noise, but rather increases noise quite substantially (at least in this forum).

I see the potential spin here that certainly relates to the Bybee mojo. Paramagnetism is one way to achieve room temperature levitation, carbon sheets are sold from many sources for science fair projects. To the untutored seeming magic, or maybe room temperature super conductivity.:)
 
What can I say? I have experienced a virtual 'miracle' in my own lab. Yet, I have no real idea why it works. I tested my Tech, yesterday, and now he is 'Wow'd' just like me. Demonstration is necessary with this 'tweak'. I hope to do some listening test differences in future, as Jack also gave me the prototype of the Bybee-Curl module as well. More in future, but I can't argue with 'non-believers'.
 
Oh, i wasn't questioning the potential for BS! ... If somebody makes untestable claims about magic materials the discussion probably belongs in the snake oil thread.
The natural media for birth notices of snake oil products is in (pseudo) scientific places. It is only after a long growing process that they join their dedicated thread.
Long life to the new Bybee's baby and happy new year to all of us :)
 
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What can I say? I have experienced a virtual 'miracle' in my own lab. Yet, I have no real idea why it works. I tested my Tech, yesterday, and now he is 'Wow'd' just like me. Demonstration is necessary with this 'tweak'. I hope to do some listening test differences in future, as Jack also gave me the prototype of the Bybee-Curl module as well. More in future, but I can't argue with 'non-believers'.

It's not a question of "belief", nor is there an argument. You say you "experienced a miracle". OK, fine. But you have not described what you experienced nor said what made it miraculous, so there is nothing to argue about or believe in. I am willing to accept your statement at face value, but so far you have not said anything meaningful about your new "experience". You haven't even said whether it involved sound reproduction, let alone what seemed to change and in what manner.

I look forward to hearing more about this miracle. I hope you have a happy and healthy new year.
 
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