[time-nuts] Sayrosa 607B Frequency Synthesizer

[Mike Millen]

GandalfG8 at aol.com wrote:
> I haven't seen too many of these in the wild so can I  assume this
> was the unit recently sold on Ebay?

It was indeed.

> If so you got an excellent drive unit at a very good price, even if it
> isn't working at the moment:-)

That's just what I thought.  It's beautifully made... probably cost the 
taxpayer a fortune in its day.  :)

> FCO standard equipment with these was the HCD-1519 1MHz frequency
> reference and whilst they are specified to run from 1, 5, or  10MHz

I've tried it with both 1MHz & 10MHz & it locked up straight away with both.

> Is there a number showing on the display to go with your "Fault"
> indication, and are any other of the indicators illuminated?

Sorry... I should have mentioned that in my first post... it's showing Fault 
4.

> It's possible a link may be required on one of the rear  connectors to
> enable stand alone operation but again I can't remember offhand so
> will check and come back to you on that too, but there shouldn't be
> any  significant wiring needed.

That's what I'm hoping.

> Like much equipment from that era though these units suffered the
> dreaded tantalum capacitor disease and it's quite possible that one
> or more modules may  be afflicted.

I brought it up gently on a variac, monitoring the rails as I went. They 
were all good until I reached 240v, then one of the +12v rails went to 0v.

I traced it to a s/c tantalum in one of the modules.  :-)  All OK now.

I'll be extremely pleased if you're able to shed any light on "Fault 4", 
Nigel, or what jumpers/connnections I might need to make.

If you have any printed data I'd be happy to pay all your costs for a copy.

Regards,
Mike
M0MLM



> In a message dated 25/11/2012 09:39:11 GMT Standard Time,
> mike.millen.uk at gmail.com writes:
>
> This  unit is a part of the UK's Diplomatic Wireless Service's
> "Piccolo" HF
> RTTY  network.
>
> I have acquired one of these & am trying to get it  working.
> It accepts a 10MHz (or 1 or 5) reference & the output can be  set to
> any frequency between 3MHz & 29,999,900Hz, in 100Hz  steps.
>
> My unit is showing a "Fault" LED on the display, which I believe  is
> inhibiting the output. I can see a varying frequency at the o/p
> socket, but  only a few mV, not the 1v into 50R as is normal.
>
> I suspect that the  fault indication is because there's nothing
> plugged
> into either the "Keying  Frequency Control Input" nor the "Carrier
> Frequency Control Input"  sockets.  (There's also a "V.F. Inputs" &
> "Carrier Output (BCD)"  sockets.)
>
> Can anyone help with a manual or connection details for the 2  input
> sockets, please?