Hi,
The unloaded Q is above 3 million, which is another way to measure how
unusual these are.
If I had schematics I would be more inclined to do something.
Cheers,
Magnus
On 12/08/2017 05:58 PM, Bob kb8tq wrote:
Hi
One risk is that the oscillator may have drifted further than one can easily
adjust it by
just changing a select cap. That seems silly when we are talking about < 1 ppm,
but
the 8600 is an unusual OCXO. The electrodes BVA is not your run of the mill
crystal.
The “air gap” (actually a gap in vacuum) puts a pretty small capacitance in
series with
the normal crystal equivalent circuit. That cuts the practical tuning range
down quite
a bit….
Bob
On Dec 8, 2017, at 11:44 AM, Magnus Danielson <mag...@rubidium.dyndns.org>
wrote:
Hi,
Many include a EFC offset pot, but when you go out of range on that, as I have
for one of mine, here is no real option execept pop the lid and potentially
find a cap or change a cap. I have not seen any as I recall, but should maybe
take a look.
However, the value for me is not to have it as sharp 5 MHz source, but very low
phase noise and high stability source as reference for measurement. The offset
error is less of a concern then, so that is why I have not spent quality time
to fix it.
Cheers,
Magnus
On 12/08/2017 04:52 PM, paul swed wrote:
I took a quick look at the spec sheet.
It appears coarse adjustment is an option M and would actually be a pot.
That speaks to another tuning diode for coarse? Or a pot on pot arrangement.
That sounds ugly.
Regards
Paul
WB8TSL
On Fri, Dec 8, 2017 at 10:17 AM, Bob kb8tq <kb...@n1k.org> wrote:
Hi
It is quite possible that nothing is actually broken and that the crystal
has simply drifted
outside the tuning range. It should be pretty easy to spot the coarse
tuning device once
the package is open. I would bet you will find a selected capacitor across
the coarse tune or in
series with the coarse tune. Changing the value of that cap should bring
things back on
frequency. I would avoid changing caps across the EFC tuning diode.
Bob
On Dec 8, 2017, at 8:05 AM, Ulf Kylenfall via time-nuts <
time-nuts@febo.com> wrote:
Gentlemen,
We have an Oscilloquartz OCXO 8600-3that cannot any longer be adjusted
into 5,000,000 Hz.It is about 1 Hz out of 5 MHz and turning
coarse/fineadjustment potentiometers cannot bring the frequencyinto its
specification.
Oven temperature is about + 80C accordingto the thermistor and the
operating voltageis at 24 VDC.
Have Googled but the only thing that turns upis datasheets w/o any
details.
Before I take it apart and start lookingfor obviously broken components,
isthere anyone that has a CLIP on this unit?
73
Ulf Kylenfall - SM6GXV
_______________________________________________
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/
mailman/listinfo/time-nuts
and follow the instructions there.
_______________________________________________
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/
mailman/listinfo/time-nuts
and follow the instructions there.
_______________________________________________
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
_______________________________________________
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
_______________________________________________
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
_______________________________________________
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
