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Henlow ?
Most most of them ended up at raf
sealand .. some are still there !
Its early days yet , have etched some
rocks in the past , this will be a bit of a
trial run, the xtals are no use now as
the qrg as soon to be swamped in wide
band nose , or so we are told ,
But from what im told , these are the gold
flashed , wire connected types , so until we see
if its possible to gain access , there's no
panic
mfg facility .. suppose , then number of
xtals used in the kit , then that would
of made sense back then .. and what
a handy 'facility'
73 -G..
Sent: Thursday, April 11, 2013 7:56 PM
Subject: Re: LF: Wanted 10XJ or FT243 XTALS Range 236.25 236.75
KHz
Graham
Been reading the mail on Yahoo.
Before you start attacking those xtals its best to find an expert.
For these reasons.
a/ Crystal grinding is a specialised art. It requires the xtal to be
perfectly parallel
b/ If you don't do the full process like grinding, polishing and
etching the xtal will "age" and at some point will jump frequency or stop all
together.
c/ Etching alone is OK for very small shifts but will attack the
edges of the xtal so it won't be flat and it will become less active and again
can stop.
I am not sure of my facts but if you just grind it creates a
condition like when plaster comes away from the wall. The abrasion creates
subsurface cracking so it is necessary to etch this away otherwise it will jump
or stop.
What I am trying to say is that serious xtal grinding needs to
be done in the proper process. Granted a small shift can be done. I am sure
loads of hams have done it and got away with it but it may pay to find an
"Expert" to help.
The local RAF camp at Henlow had a Quartz Xtal manufacturing
facility years ago and one of the people there was G4ALR. He doesn't have his
e-mail on QRZ but I may be able to get it. I think he is an "expert" in the
field.
If you like I will chase him for info?
73 es GL Pete M0FMT IO91UX
BOGOF : ))
Sent: Thursday, April 11, 2013 7:17 PM
Subject: Re: LF: Wanted 10XJ or FT243 XTALS Range 236.25 236.75
KHz
Pat there's something up with your e-mail because it keeps sending
the same thing twice? i.e. two e-mails for the price of one.
73 es GL Pete M0FMT IO91UX
Well, you might have been happy,
Pete. I discovered that the family cat's whiskers wouldn't work with a bit
of coke and we had to go back to a pair of baked bean cans and
string!
On 11/04/13 16:20, M0FMT wrote:
And we all live in a hole in the road but we were
happy!!.....:0)
73 es GL Pete M0FMT IO91UX
And Wireless Set No.17 for
£2:19:6 (2Volt accumulator and HT Battery 10/- extra)
And we're
all getting older!
73
On 11/04/13 12:18,
M0FMT wrote:
Hi Graham
How young you are my introduction to Tottenham Court Road
(Proops?) , Lisles Street (GW Smiths), Charring Cross and The
Edgeware Road about 1956. Aaaaah those were the days. learnt a lot about
Radio, Life, the Universe and everything there......
hee!
Got my R107 from Lisle Street with money save from my
apprentices pay. Carried it (abt 1 CWT) via bus to Kings Cross
in the days when the conductor would jump off the bus and give you had
to get it on board........ imagine that on a "Bendy Bus" today. See http://www.retinascope.co.uk/lislestreet.html for
the full story.
OK on the stick info yes but I am CW only really can't get
too excited about sterile data although as you know I do partake occasionally.
73 es GL Pete M0FMT IO91UX
R Pete
Well , its possible to use the emergency
vfo , but that results in a very
unstable signal , I remember down the
Tottenham court road , there where tea chests of
crystals , but that was 1970 .. seems a
lot of the traditional firms have closed ,
One of the £5 dds with a
driver would work , but they want to
keep it standard
DS - That's really the 'correct'
situation , that -33 db decode, -3 db
lower than normal was a good
indication that the system is working
, over ranging the a/d is
the only problem . I think dynamic range
is 60 d b after processing , is it 3
db per bit ? 8 bits , 24 db +
3 that's 27 dB ? 500:1 ? ,
but by removing qty
2 mixers and 2 oscillators
, [ may be 3 oscillators 1 , hf-up-conv 2 ,
pll conv osc 3 ref osc ) that is
a lot of noise + jitter removed from
the signal path as well as imd
from 2 mixers , I found a attenuator
helped for mw and I have a
mw-filter , which cleaned up sw
bands ...... nice to have a panoramic
display , 2 mhz this time , the ra17 was 1
mhz and 28 valves + 20 ish > in
the radio
73-G.
Sent: Thursday, April 11, 2013 10:47 AM
Subject: Re: LF: Wanted 10XJ or FT243 XTALS Range 236.25
236.75 KHz
OK Graham
Thought it was home brew retro.......... I am in that
mode and think everbody else is! What do you do at the moment inject
a Sig Genny?
Have you checked the net or checked out Vincent -
QuartzLab etc?
Anyway what's that master osc circuit. I build from old
RADCOM (pre 1975 when they published real amateur radio) and PW,QST
etal. I use modern xtals with no known issues. Well trying to get
third overtone for 10m not to chirp is an issue with me at the
moment.
OK yes got a stick on its way didn't want to tear up my
existing upconverter design. But not sure there is much wrong with
the UC approach it works for me. But want to try the direct
approach. Do you get much Cross mod and IM
products?
73 es GL Pete M0FMT IO91UX
Ok Pete
Q where to have them made ?
The set , Marconi Ocean span 1950's
valve tx needs the big
rock's as the oscillator pass's
quite a lot of power via them
...hc6u are no good , drive level is very
low - the ones fitted are the wired- gold
flashed ones , so cannot etch into
the band ...
the gang want to keep it
standard
73 -G.
Ps waiting for qty-3 £6
dongles : )
Sent: Wednesday, April 10, 2013 11:43 PM
Subject: Re: LF: Wanted 10XJ or FT243 XTALS Range
236.25 236.75 KHz
Hi
If you want to spend a small fortune get them cut.
However build a Mixer VXO from El cheapo standard xtals and or old
PMR rocks. Then at your next rally buy a couple of Screw together
10xj or FT243 rocks of any frequency and put the El-cheapo xtals
inside. And Hey Presto you have Retro rocks.
I have a small all valve 472 tx that uses 6.00
-6.472=0.472 vxo-able a couple of kc/s 12ax7-6am6-6cl6= 4wattso/p.
Local QRP rig.
Hope this helps
73 es GL Pete M0FMT IO91UX
Wanted 10XJ or FT243
XTALS Range 236.25
236.75 KHz
Q Is there any manufacture
of crystals in this range ?
Or Surplus items
available
QTY 1 or 2 off
TNX- Graham
G0NBD --
73 de pat g4gvw
es gd dx
qth nr Felixstowe
East Coast UK --
73 de pat g4gvw
es gd dx
qth nr Felixstowe
East Coast UK
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