[time-nuts] SRS FS700 questions
GandalfG8 at aol.com
GandalfG8 at aol.com
Sat May 3 17:05:32 EDT 2014
Many thanks for the advice, I was a bit concerned about making any
adjustments until I'd confirmed it at least appeared to be working correctly but
I've just taken another look at the manual and can't see any reason why I
One of my reasons for concern was that although this isn't an option 01
unit SRS seems to have upgraded the OCXOs to beyond the original basic spec,
it's currently fitted with an SRS low noise SC10, and as it stands I'm
getting the impression I'd be better off just killing the Loran input and
letting it free run:-)
BTW, the SC10 OCXO manual seems to be one of the few SRS manuals available
online that does contain the schematic.
Thanks too for the feedback on the LCD backlight, I've found nothing so far
to suggest it should be backlit but it could certainly do with it.
In a message dated 03/05/2014 20:19:14 GMT Daylight Time,
stanw1le at verizon.net writes:
I would consider doing the maintenance/calibration/performance
verification procedure in the manual.
A procedure will show if you have equal swing on the VCXO about the
center freq needed.
The VCXO can be mechanically adjusted for center of the VCXO electronic
I recall no backlight on the LCD on mine.
It has been awhile since I last turned mine on.
On 03-May-14 12:57 PM, GandalfG8 at aol.com wrote:
> My FS700 arrived yesterday, complete with bonus artistic effects due to
> the sender believing a thin coat of bubble wrap with an outer layer of
> cardboard cut from a box and just taped on top, no padding or air gap,
> the obvious way to ship it:-(
> Physically at least it seems to have survived remarkably well, no damage
> the BNCs and the front panel trim, outer covers and transformer cover
> looking pretty good again after a couple of hours work.
> Not having any rack ears attached was probably quite a bonus with it
> shipped like this!
> The only obvious internal "damage", and it might have been that way
> shipping anway, are three vertical inductors held to the circuit board by
> silicon rubber or hot melt adhesive that are loose but still seem to be
> electrically connected
> Anyway, it powered up ok and is indicating it's locked onto Anthorn in
> Lessay chain, even if it does believe it's found the never built station
> Loop Head in Ireland:-), but I'm not sure if it's functioning properly.
> It's close enough that I don't want to start pulling it apart for the
> of it without being sure, and it may just be a case of waiting for it to
> settle, but after showing as "locked" for several hours the 10MHz
> indicated both by the internal display and an external counter, is
> back and forth quite rapidly anywhere within approx +/- 3 parts in
> There was an obvious change in the crystal oscillator frequency as the
> warmed, and another when the conditioning seemed to take over, but
> been "hunting" like this ever since it first indicated lock and with no
> obvious change, just when I do think it might be converging it "opens
> So first question is, can anyone tell me please if this is "normal" or
> close enough that I should expect it to settle eventually, or do I need
> start investigating further?
> Second question, could somebody confirm please whether or not the LCD
> display is supposed to be backlit?
> This one isn't, but it's not immediately obvious from photos I've found
> online whether or not it should be, and although the contrast range on
> seems to be fine it's certainly not easy to see.
> Last question, for now at least:-), this unit has the FS800 PCB rev C,
> revision 2.0 firmware, does anyone know if any later firmware is
> that includes Anthorn, or at least Rugby, as part of the Lessay chain?
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to
> and follow the instructions there.
time-nuts mailing list -- time-nuts at febo.com
To unsubscribe, go to
and follow the instructions there.
More information about the time-nuts