Do aging Drake crystals lose accuracy?
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Yes, ALL crystals drift with age. Strangely enough, it's called 'aging'!! :-)
The rate at which they age varies with the cut of the quartz, frequency, the manufacturer's quality
control, storage temperature, operating current, etc., etc., etc. The original frequency spec is
+/- 0.003%.
Someone I know used to write on crystals with a pencil claiming the frequency
could be changed. Is this true or an urban legend, because graphite is
crystalline?
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- Original Message -
From: Neil M Califano cchange...@yahoo.com
To: Drakelist@zerobeat.net
Sent: Friday, September 16, 2011 5:05 PM
Subject: [Drakelist] Changing crystal frequency
Someone I know used to write on crystals with a pencil
claiming the frequency could be changed. Is this
On Fri, 16 Sep 2011 18:31:39 -0400, Garey Barrell wrote:
Yes, ALL crystals drift with age. Strangely enough, it's called 'aging'!!
:-)
Interstingly enough, the 40 Meter crystals (at least in the C-Line era) seem to
age less gracefully than most.
73
-Jim
--
Ham Radio NU0C
Lincoln,
- Original Message -
From: Richard Knoppow 1oldle...@ix.netcom.com
To: Neil M Califano cchange...@yahoo.com; Drakelist@zerobeat.net
Sent: Friday, September 16, 2011 7:32 PM
Subject: Re: [Drakelist] Changing crystal frequency
Did this myself in 1960, and it works. The added mass will
- Original Message -
From: Jim Shorney jshor...@inebraska.com
To: Drakelist@zerobeat.net
Sent: Friday, September 16, 2011 6:41 PM
Subject: Re: [Drakelist] Drake crystals accuracy
On Fri, 16 Sep 2011 18:31:39 -0400, Garey Barrell wrote:
Yes, ALL crystals drift with age. Strangely
The older (FT-243 style) crystals could be opened with just three small screws. The rectangular
piece of quartz could be removed and cleaned, -OR-, you could make marks on it with a pencil to
LOWER the frequency a very small amount. Essentially you were just adding a little mass to the
Jim -
I don't know about that on the C-Line. The 40M crystal in the 2-B is definitely more 'failure
prone' that the others, but I think that is because of the oscillator circuit Drake used. The 40M
crystal is the 'last' (highest) fundamental crystal used, the next one up is run in overtone
On Fri, 16 Sep 2011 22:07:04 -0400, Garey Barrell wrote:
Perhaps the 40M crystal is confused about which mode it's supposed to be
in?!?! A new 6EA8 seems
to 'fix' a large number of these crystals.
Does it fix them when they are 40 KHz off?
73
-Jim
--
Ham Radio NU0C
Lincoln, Nebraska,
There are crystal made cheaply and then some made with more labor and
usually are more expensive. Better ones are slowly ground to frequency.
Cheaper ones are ground close to frequency and then doped to bring them
on frequency. This process is faster then the prior one. However, the
doped
Rubbing solder on instead of graphite works a little better as the lead has
more mass then graphite. Thus, the oscillations are slightly less and the
lead can lower the frequency slightly more then graphite.
Lee Bahr, w0vt
-Original Message-
From: Neil M Califano
Sent: Friday,
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