Hi Mikael,
Many thanks for the offer of the photos.
I'm in no immediate panic, I'm not expecting to have my hands on the FS700
itself for another week or so, but if I haven't located any scans in the
meantime that would be very much appreciated.
Regards
Nigel
GM8PZR
In a message
Now there's an interesting part number for a scanner:-)
I've had similar problems in the past trying to stitch schematics, I did
find a program some years ago that would half work, usually matching up
the ends of the lines ok, but then leaving quite significant distortion in
that region. I
On Mon, 21 Apr 2014 17:12:54 +1200
Bruce Griffiths bruce.griffi...@xtra.co.nz wrote:
Optical excitation of quartz resonators: Electronics Letters
http://digital-library.theiet.org/content/journals/el, Volume 18,
Issue 9 http://digital-library.theiet.org/content/journals/el/18/9, 29
April
On 04/21/2014 11:40 AM, Attila Kinali wrote:
On Mon, 21 Apr 2014 17:12:54 +1200
Bruce Griffiths bruce.griffi...@xtra.co.nz wrote:
Optical excitation of quartz resonators: Electronics Letters
http://digital-library.theiet.org/content/journals/el, Volume 18,
Issue 9
I'm puzzling over this statement. The FT-243's I have seen have a spring
that squishes the quartz blank between the electrodes. They aren't plated
onto the quartz, but they are still in intimate mechanical and electrical
contact.
-Chuck Harris
Bob Camp wrote:
Hi
The WWII era FT-243 is one
In my over 50 years of active ham radio experience as well as in my
professional one, I have literally taken apart 10s of thousands of crystals,
and, have never seen a single on where there has not been a physical contact
with the quartz. That of course includes the most common FT-243. Regards -
Hi
If you look closely at most of them, the plates are not flat. They are higher
on the edges than in the center. There’s a gap in the middle. If you don’t have
the gap, the blank is constrained by the big heavy plate. That damps the
resonance and lowers the Q.
Bob
On Apr 21, 2014, at 9:00
On Mon, 21 Apr 2014 14:54:12 +0200
Magnus Danielson mag...@rubidium.dyndns.org wrote:
They used a 10mW HeNe laser, modulated with 1kHz to 1MHz on
various quartz cuts (X+5°, DT, AT) and could measure oscillations
of the quartz using metal electrodes.
The mechanism of exitation was
Agree there are some like that, but, only a few. A large spring loaded plate
is not going to dampen a piece of quartz vibrating in the MHz range at all.
Granted, the sealed, and metalized construction is a better one, but it is
mostly done to minimize shock and impurities. - Mike
Mike B. Feher,
Hi
One of the reasons for going to plated electrodes was to control the damping on
the resonator. You control plating thickness fairly tightly for this reason. A
great big lump of iron on your vibrating area does indeed damp it.
Bob
On Apr 21, 2014, at 9:29 AM, Mike Feher mfe...@eozinc.com
On 04/21/2014 03:18 PM, Attila Kinali wrote:
On Mon, 21 Apr 2014 14:54:12 +0200
Magnus Danielson mag...@rubidium.dyndns.org wrote:
They used a 10mW HeNe laser, modulated with 1kHz to 1MHz on
various quartz cuts (X+5°, DT, AT) and could measure oscillations
of the quartz using metal
Hi
If you are going to thermally excite the resonator, and measure the resonance
optically, there’s no reason at all to use quartz. There are other materials
with much higher acoustic Q than quartz.
Bob
On Apr 21, 2014, at 9:47 AM, Magnus Danielson mag...@rubidium.dyndns.org
wrote:
On
No. There is just a little rectangular quartz wafer. No plating.
In fact, post WWII, when many ham transmitters were 'rock bound' (ie:
crystal conteolled) it was common pratice to regrind mil surplus rystals
to move them into the ham banda.
Apparently, some were also etched using a cleanser
Hi
Early in the WWII era, quartz blanks were not commonly etched after begin
ground / polished to frequency. This left debris on the surface of the blank.
The net result was that the resonators failed after a period of time in the
field, especially under damp conditions. The problem got so bad
In message a5032606-d7d7-4231-b1bd-434670274...@rtty.us, Bob Camp writes:
Early in the WWII era, quartz blanks were not commonly etched after
begin ground / polished to frequency. This left debris on the surface
of the blank. The net result was that the resonators failed after
a period of time in
Who said they were plated?
-Chuck Harris
J. Forster wrote:
No. There is just a little rectangular quartz wafer. No plating.
In fact, post WWII, when many ham transmitters were 'rock bound' (ie:
crystal conteolled) it was common pratice to regrind mil surplus rystals
to move them into the ham
The etching referred to was by post-war hams,
-John
===
Hi
Early in the WWII era, quartz blanks were not commonly etched after begin
ground / polished to frequency. This left debris on the surface of the
blank. The net result was that the resonators failed after a period of
Hi
As with all “good stories” there are many versions told by many people. I’ve
heard far to many mutually contradictory versions to have any real idea what’s
true. You are correct that etching was a known process in the 1930’s and that
it had been used by various people at various times.
Hi
Well I can name at least one post war ham (me at age 14) who did not understand
the need for etch after grinding…
Bob
On Apr 21, 2014, at 11:21 AM, J. Forster j...@quikus.com wrote:
The etching referred to was by post-war hams,
-John
===
Hi
Early in the WWII
Bob,
We all start somewhere.
Today one buys aged equipment with fancy synthesis so that fooling
around with crystals, etching or graphiting them won't be necessary.
Hell, someone taking the time to calibrate their transceiver is rare
these days.
Cheers,
Magnus
When this question was first posed, AOM's first jumped to my mind. An AOM
(sometimes AOD) is an Acousto-Optic Modulator that works by setting up an
acoustic wave in a crystal. When a laser is directed through (or reflected by)
an AOM, it is deflected.
One way to think about this is the
The FT-243 holders I revamped in the 1950s and 60s did have the aforementioned
spring. However a close look at the electrode plates that contacted the quartz
resonator had, in every case, a raised boss at each corner that spaced the
center of the electrode a few mills above the center of the
Hi
Yup, little high spots on the corners of the metal plates. Put the plates in
“upside down” and the crystal stopped working ….
—
If you want to dig into the WWII stuff Virgil Bottom was always happy to talk
about his role in saving the world by fixing the crystal process. There are a
Good afternoon very interested in the work you are doing with the STM board.
As I mentioned far earlier in this thread I am attempting to use it to
correct the BPSK WWVB signal here. Initial thoughts were using FORTH to
program the STM board.
Very curious what you are using as examples.
My
Perhaps this thread should go off line not to distract from the originators
thread.
Regards
Paul.
On Mon, Apr 21, 2014 at 4:29 PM, paul swed paulsw...@gmail.com wrote:
Good afternoon very interested in the work you are doing with the STM
board.
As I mentioned far earlier in this thread I am
I just changed the thread title to BPSK Processing
If you are having problems with the software what you need to do is start
working on it in an easier environment. That would be some IDE like
Eclipse on a standard desktop or notebook computer.You can feed your
software made-up test data
Actually GCC supporting Cortex. So, I am using Raisonance IDE plus GCC
Toolchain as a development environment. My current project functional
diagram is following:
+--- STM32 -- (Pulse Counter, TTL Generator, DDS
driver, GPSDO monitor)
GPSDO--LTC6957-3--| |
Will be travelling on business so will be out of touch next day or two.
Regards
Paul
On Mon, Apr 21, 2014 at 7:35 PM, Chris Albertson
albertson.ch...@gmail.comwrote:
I just changed the thread title to BPSK Processing
If you are having problems with the software what you need to do is start
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