Hi Walter I looked at one of those on eBay but bearing in mind your previous
warnings about some Rb lamps..... it went beyond my (mean) bid. It looks
like another case of "ten year life lamps" ??
Cheers de Alan G3NYK
----- Original Message -----
From: Walter Blanchard <[email protected]>
To: <[email protected]>
Sent: 16 May 2006 12:28
Subject: LF: Rb standard
A number of TAIT T801 frequency standards have just appeared on the UK
surplus market.
They're ex-cellphone bases and I understand have been ditched in favour of
GPS-locked standards.
Consist of an Rb standard driving a couple of 12.6 MHz synthesizers that can
be digitally offset by a few Hz.
The interesting bit is the Rb standard which is a Frequency Electronics Inc.
model 5660A.
Its output is 10 MHz and on switch-on it ramps up and down over a few kHz
searching for Rb lock. You can see it on
a frequency counter. If it's working then after about 3-4 mins it stops
quite suddenly and the "Lock" light
comes on, if not it goes on searching forever and the lock light stays off.
Unfortunately the ramping is a built-in
software function and (unless somebody knows better) can't be switched off
so if no lock not
useful as an ordinary 10 MHz. osc. When locked, can be set precisely on
frequency with a small trimmer.
Anybody know anything about these units? FEI website not very helpful.
Have checked four and three were dead. The good one had a 2000 datestamp,
the
others 1996-1998 so might be a clue there. I sent an email to FEI asking how
long they were good
for but no answer.
Walter G3JKV.
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