[Test-Equipment] re Wavetek (Rockland) 5120 manual needed

[Alan Melia]

Hi Mike I am also in the UK, a lot of these have been released by the
Military and some no longer function correctly. I have been totally unable
to find any circuits or service data, and would be very interested if your
plea turns any up. In the meantime I have made some progress with localising
a similar fault on one of my units. I suggest your contact emails me direct
and I will try and feed him what information I have.

For any other users....

The synthasis seems to be done in two parts the 100kHz to 160MHz digits are
accomplished in the screened boxes on the mother-board The digits below
100kHz seem to be generated on two unscreened pcbs which seem to contain a
TTL DDS with a discrete transitor DAC on the output. The output is via the
cSMA connector marked "10MHz OUT" and in fact contains 1.000000 tp 1.9999999
MHz depending on the low digit setting The fractional MHz are 10 times the
digit setting I think. This is then added into the high digit signal. I have
not made any progress with this yet, but it does seem to be a common area of
failure. I have asked for any information on any Rockland product that might
contain a low frequency DDS as the congiguration will probably be similar.
The pcb contains lots of 74LS283s which are 4 bit full-adders, and
register/buffers.

Heres hoping some paperwork turns up eventually, they are nice units when
working. My faulty one was intermittant, and looked like it might be a PSU
or electrolytic problem, but I have not found a solution yet. I have not
tried swapping pcbs from the good and bad units.

I hope that will help just a little
Regards
Alan G3NYK
alan.melia (at) btinternet.com
(I think you can work that one out....but its non-clickable this way)