On Jul 10, 1:09*pm, John Byrns wrote:
In article ,
*Patrick Turner wrote:
On Jul 10, 3:48*am, John Byrns wrote:
In article
,
*Patrick Turner wrote:
On Jul 9, 9:19*am, John Byrns wrote:
[Much off topic drivel snipped]
You may well delete "drivel" like so many others here who have awful
personalities who cannot cope with being human or nice in any way. Ah
you going senile? Just can't cope with well rounded discussions? Its
OK, you don't have to hide such characteristics.
Your drivel is a fine topic for discussion, the problem is that it is off
topic
in this group and you should take it elsewhere.
I see no reason not to include some background information which
indirectly relates to the subject.
I don't see how your so called "background" information relates even
"indirectly" to the subject, it just plain doesn't belong in this group.
Well then we'll just have to agee to disagree. But I like to talk
about Sex, Politics, Religion, and Economics at dinner parties. I find
small talk tedious and boring if not spiced up with some off topics. I
thus get called a "raving left wing Grade A arsole" and so forth on
regular basis for daring to challenge the validity of the limited
perceptions of others which seem to be set in concrete. To un-set the
concrete, and allow flows of ideas I can come across as smooth as
grade 6 sand paper and I don't give a ****. For flows of ideas,
readers of this rec.audio.tubes site should be active with a soldering
iron and Get Off Fat Arses And Do A Lot Of Something, ie,
GOFAADALOS !!!! :-) :-) And it'd help if they were FREE in how
they come to the site to talk about anything at all.
Someone said to me yesterday, "I'm black or white. I only ever see
black or white" She's the wife of a tech I employ, and can be rather a
stern old lady. "Ah", I said, "ever thought that there might be other
colours, like red, or green? Maybe blue, yellow?" She goes, "Nah,
black or white." Maybe that's why her husband don't talk to her much -
she's intimidating. But I mentioned, "Surely there'd be some green in
how ya see the world, no, because surely there'd be a bitta the Irish
in ya". She still wouldn't smile. Like a lemon. No sense of humour.
What ****s me are old people who don't ask any sensible questions and
seek only to disprove others while NEVER constructing something new
and better within the field of their interests, and definately never
trying out anything different to see if it works.
If you now think I have been off topic, no apologies, because its not
wrong to be opinionated.
Don't worry, when, or if I become senile, i'll not recognise 5% ona
CRO when its there. But most waves at that site showed slew
distortions and cut off distortions and so forth, all of which can
easily be avoided or minimised to be below 1% with my circuit over a
wide AF range and if the output voltage 1 Vrms.
Yes, there are plenty of distortions shown to illustrate the various problems
that can occur in a poorly designed detector, and what causes the distortions. *
There are also plenty of undistorted waves shown at that site, with distortions
of less than 1%, to illustrate the good results that can be achieved with
careful design.
Because my home brew test signal of modulated RF waves isn't perfect,
the distortion within the envelope is probably 1%, and hence if I
measured the THD of the AF after its been through the AM radio i would
get THD of detected AF 1%, certainly at say 95% modulation.
So to see how much THD is introduced by the radio set one may use a
dual trace CRO to display both test
signal at the radio input and the detected AF and overlay the waves to
see how they compare. Using as much of the screen as possible, its not
difficult to see if there is less than 1% of additional THD added by
the radio set. All that takes time but its a very simple thing and I
cannot understand why you would not have tried out all sorts of AM
detector ideas like I have to see what works best for you. What the
**** impedes your progress to your workshop and soldering iron? If you
have a broken leg, or are impaired or disabled in some way, then let's
hear about it.
But even where one
listens to short wave where AF detector output 0.1Vrms, the sound is
good, although rather mauled by having travelled so far and being so
riddles with noise and fading up and down. I have never ever seen any
old radio or any old schematic of what was used for detecting AF for
use in re-broadcasting.
I found a schematic for an old Telefunken AM rebroadcast receiver, a.k.a.
"Ballempfänger", on the web. *It was a rather complex radio although IIRC it
used a straightforward vacuum diode detector.
Nothing wrong with vacuum diode detectors if used wisely. They might
be used instead of how I have used Ge diodes with CF. They all work
best with low Z signal sources.
I googled Telefunken AM rebroadcast receiver "Ballempfänger"
Nothing to be seen.
AFAIK, not one single commercial example
exists of a radio with "infinite impedance detector" even though the
Selsted & Smith example is given in RDH4, page 1,495, Figs 27.56,
27.57
RDH4 does not have anything that works as well as what I invented for
myself 14 years ago.
In the US J.W. Miller offered both commercial AM tuners and Radios using the
infinite impedance detector, I have one of their AM Tuners. *Altec Lansing also
offered an AM-FM tuner that used the infinite impedance detector in the AM
section. *Sargent Rayment also offered a line of tuners and receivers that used
the Selsted & Smith detector in the AM sections. *Ampex also built an AM-FM
tuner that used a perverted variant of the Selsted & Smith detector, I also have
one of these.
I've never seen any of these things in Oz or any of their schematics.
Infinite Z detector isn't bad, but gives very low output.
It's hard to beat a carefully designed diode detector though.
Depends. Most are distortion generators.
Most bean counters justify their employment by being able to reduce
the parts and labour needed to make something, and therefore
increasing shareholder profits and most often reducing the sound
quality and reliability in electronics produced by the company.
The opposite approach, of adding components that serve no useful function is
just as bad, actually worse.
Each unto their own. everyone has a different way of doing things, and
commercial competition stifles anyone who dares to use one more nut,
bolt or resistor than the ****ing opposition brand. The result is that
they all have competitions to seewho can dumb **** down the most while
maintaining enough sales for the shareholders to dine well.
If it makes you ill to use one more cathode follower than someone
somewhere said could be superflous, then don't. But I will. In my
vicinity there are no shareholders or bean counters, and my clients
get a good deal without having to pay for someone's Cadillac or
expensive lunches, neither of which contribute to sound quality.
Patrick Turner.
Regards,
John Byrns
Surf my web pages at, *http://fmamradios.com/- Hide quoted text -
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