clifto wrote:

COLIN LAMB wrote:

Ok, finally found a single tube 100 kHz. crystal oscillator that uses a neon
bulb relaxation oscillator that is synchronized to achieve 10 kHz signals.


Phase Locked Lightbulbs?


Not really so bizarre; there are stories of certain computers with light-
sensitive neon bulbs in the logic that were affected by ceiling fluorescent
lighting when panels were removed from the racks...

Regards,

Michael

On Sat, 29 Sep 2007 02:12:13 -0500, msg wrote:

clifto wrote:

COLIN LAMB wrote:

Ok, finally found a single tube 100 kHz. crystal oscillator that uses a neon
bulb relaxation oscillator that is synchronized to achieve 10 kHz signals.


Phase Locked Lightbulbs?


Not really so bizarre; there are stories of certain computers with light-
sensitive neon bulbs in the logic that were affected by ceiling fluorescent
lighting when panels were removed from the racks...

Regards,

Michael
The trigger point does shift with light or RF. Black paint on the lamp
will take care of the light.

In my "junk that should have been thrown away" I have a frequency
counter that I built from an artical in QST many years back that used
10 neons per digit. Many years after the fact I realized that it might
have been more practical if the Neon high voltage had been gated off
during the counting phase and on only to display the count. But then
it would not have looked nearly as impressive during operation.

John Ferrell W8CCW
"Life is easier if you learn to
plow around the stumps".

"clifto" wrote in message
...


Phase Locked Lightbulbs?


There was a circuit where numerous NE2s were wired on the circumference of
a circle as individual relaxation oscillators. At first, the firing pattern
was
entirely random, but over time the lamps would synchronize and fire in
order!
The light from an adjacent lamp would lower the firing point the one next to
it.

Pete

The neon bulb was a wonderful device for a young boy to play with - and for
those that do not entirely grow up. It energized at about 60 volts,
although that varied from tube to tube. ARC-5 receivers used them across
their input, to discharge static electricity. They were great for hams with
meager funds since you could place one near the final and determine if there
were parasitics, by the color of the glow.

Sensitivity could be increased by putting a dc voltage on the plates just
under what it took to fire. Then, a slight amount of rf would add to that
base and fire the bulb.

Little pocket testers would distinguish between ac or dc, by simply looling
to see whether one or two plates were lighted.

Light wuld affect the sensitivity, as well as heat. You could apply a
voltage just under the firing voltage, then put your finger near it and it
would light.

Although I never built one, it probably would have made a great lightning
indicator, with directional probes connected to indicate which quadrant the
lightning was coming from.

As I recall, we used to salvage neon bulbs from old flouroscent light
starters.

And, of course, they were good for neutralizing those old triode finals.

73, Colin K7FM

clifto ) writes:
COLIN LAMB wrote:
Ok, finally found a single tube 100 kHz. crystal oscillator that uses a neon
bulb relaxation oscillator that is synchronized to achieve 10 kHz signals.

Phase Locked Lightbulbs?

Well no, because there's no loop.

It wasn't uncommon to inject a bit of signal from one source to an
oscillator to synchronize them.

That's what was used in oscilliscopes that didn't have triggered
sweep.

I seem to recall that's what was used to synchronize TV set
vertical sweep to the incoming signal.

THere were lots of examples.

PLL's were too costly and complicated during the tube era for
common use, and any real referenfes to PLLs in the hobby magazines
didn't arrive till the late fifties.

Early seventies, and they were all over the place, because ICs
had made them a lot more practical. ANd I suppose there was
suddenly a need; after all, most of the early PLL synthesizers
described in the ham magazines were for 2M FM use, where crystal
control was used in virtually all rigs, but the cost was too
much when you wanted a lot of channels.

Michael VE2BVW

Hi Colin

Thats the one, you've confirmed the device line-up,a 4016was
incorrectly in the place where a 4013 should have been, so it's no
surprise the marker wasn't functioning correctly.

There's a separate band-edge marker using a 3.5 MHz xtal.

Many thanks de miken, zl1bnb



On Tue, 25 Sep 2007 17:25:26 -0700, "COLIN LAMB"
wrote:

Hello Miken:

I found my 1981 ARRL Handbook. They have a "marker" generator, which uses
an LF-353, a 4001 and a 4013 - all integrated circuits. There is also a
simple 2 transistor 100 kHz oscillator.

The marker generator puts out 100, 50 and 25 kHz.

When I read the request for a circuit to supplement a glowbug, I thought a
tube crystal calibrator would be what was wanted, and thought perhaps the
later 1981 edition might have abandoned a tube version. So, I pulled out a
1972 ARRL Handbook and even then all they had was solid state.

If you are going to use integrated circuits in a glowbug receiver, you need
to hide them, since it is unbecoming and might cause others to ridicule the
otherwise heroic effort to recreate a glorious radio. A simple tube can do
a wonderful job of putting out 100 kHz signals, and if you want 50 kHz, you
can use a neon bulb divider.

Many of the simple receivers I built would have been lost with a 100 kHz
marker. A 1 MHz marker would have been more useful, and even then I was
guessing at the which MHz it was. The best marker was simply a crystal in
the ham band and a known point. Something like 3550 kHz, which could also
be used to spot at 7100 kHz. Even odd marked frequencies are useful - then
a properly hand calibrated graph laminated on the front panel (ala HRO) will
give a feeling that none of the wonderful new rigs can touch.

73, Colin K7FM

On 25 Sep 2007 23:29:55 -0500, wrote:

Is there anyone in the group who has a 1980 ARRL handbook who could
scan and email me the circuit of the xtal calibrator/marker generator.
I've a friend building replica glowbug regen receivers who needs this
info to help get his unit operational.

Maybe the following will be of help:

QST page:
* 12, May '37: "A 100-Kc. E.C. Oscillator for Frequency Checking"
uses a 24A tube
* 53, May '37: "100-kc. Calibrating Oscillator" uses a 6L6 tube
* 40, Jan '39: 1000 Kc calibrator uses 6F6 tube
* 34, Sep '41: 50-, 100-, and 1000-kc oscillator uses three switched
LC combinations and one 117L7GT tube
* 52, May '45: "Battery-powered one-tube 450- and 1500-kc. signal
generator" (1G4, 1H5, or 30 tube)
* 31, Oct '51: Uses both halves of a 6SN7 dual triode to produce
50-kc signals
* 68, May '52: "Simple crystal marker oscillator" uses a 6J5 tube
plus two resistors and 'most any crystal.
This is the SIMPLIST calibrator circuit I've seen!
* 41, Jun '52: "...Frequency Standard...Oscillator" uses a 6F6
oscillator, both halves of a 6SN7 as a multivibrator,
and a 6K8 buffer/mixer to give 100-kc and 10-kc points
* 43, Sep '52: "Fig. 2 - Oscillator circuit for a simple 100-kc crystal
standard" uses a 6AU6 tube and NO inductor!
* 40, Jul '54: Uses a 6AK5 to produce 100/50-kc harmonics
* 14, Mar '55: "Frequency Marker with 50-Kc. Intervals" uses a 6AK5
and both "halves" of a 6U8 to provide harmonics up
to 30 Mc.
* 61, Jul '59: "100-kc calibrator with 1-kc markers" uses a 6AU6
oscillator and an NE-2 sub-harmonic generator
* 30, Mar '62: Uses a 6AU6 oscillator at 100 kc and a 12AU7
multivibrator to also give 50 kc markers
* 33, Jan '65: Uses a 6AQ5 oscillator at 100 kc and a 6AS6 10-kc
sub-harmonic generator (no diode and NO inductors!)
* 34, May '65: Uses a 6AU6 oscillator at 100 kc, a 12AU7 multi-
vibrator for 10 kc points, and another 12AU7
ACCURACY: multivibrator for 1 kc points!


CQ page:
* 35, Jul '47: "A Simple Frequency Standard" uses both halves of a 6SN7
and one semiconductor diode (an easily-hidden 1N34) to
produce 1000- and 100-kc signals up to about 60 mc.
* ??, Apr '55: "500-kc Marker" uses a 6AU6 tube
* 29, Dec '55: "A Heterodyne Crystal Calibrator AND CODE PRACTICE
OSCILLATOR" uses both halves of a 7N7, 6SN7, or 12AU7
(or pairs of many triodes) and two crystals to give
marker signals at the DIFFERENCE of the two crystals

RADIO-ELECTRONICS page:
* 34, Oct '55: "Dual-Frequency Crystal Calibrator" uses a dual-
frequency crystal and a 6AK5 to produce outputs at
1000- and 100-kc. Adds a 1N34 diode and a 6BE6 tube
to make a harmonic generator. Adds an NE-51 as a
relaxation oscillator to make the marker points
more-easily recognized!
* 52, Sep '66: "Crystal Calibrator" for CB; uses a 6C4 oscillator

If those aren't enough, I can also cite several "utility oscillators"
(which are usually coil-less).

That's a great list of projects.

I've suggested to ZL2CDH who builds the glow-bug rigs, that he makes a
marker/generator using some of the hollow-state devices.

Thanks MikeN, zl1bnb

In article ,
Uncle Peter wrote:

"Mark Zenier" wrote in message
...
In article ,
The problem here is that neon bulb relaxation oscillators top out
at, according to the charts in the book, at between 10 and 30 kilohertz,
depending on bulb type.

Mark Zenier
Googleproofaddress(account:mzenier provider:eskimo domain:com)


I was curious if there was a limit on the upper frequency, and I was
wondering about the waveform as well; that is if the circuit can produce
strong harmonics up into the upper HF regions. It would be an interesting
project to build!

The book is pretty vague on the speed of a discharge. Neon lamps
are sloppy parts. They age, their characteristics vary by how much
illumination they get from other lights (or built in radiation), they
take tens of milliseconds to settle down after they've turned off, etc.
So the discharge speed is a pretty loose spec.

Scanning the scope photo of a 7 kHz oscillation and feeding it into
The Gimp (Linux's equivalent of Photoshop), it looks like the fall time
of the sawtooth is about 30 microseconds, out of a total cycle of 140
microseconds. (A 4.7 meg resistor, a 50 pF cap, and an 5AB (a tight spec
NE-2), at 140 volts). Even using just the steepest part, it doesn't look
like there would be harmonics there much higher than 100-200 kHz. High
impedance makes the waveform pretty squishy.

Mark Zenier
Googleproofaddress(account:mzenier provider:eskimo domain:com)