Mon Apr 27 04:27:16 UTC 2009
of the two sections in the D310 are not too much like the 310. It looks
more like the 500 or 3200 without the final stages. For instance the
reference frequencies in the regular 310 come from one SGC module,
whereas the D310 uses SGA and SGB. I was surprised when I found that the
D310 used different strategies than the 310.
So it is a bit different and if you look at the datasheet for the D310,
the 0.1 Hz resolution is standard. I certainly expected the 310 and D310
to be based on the same design, but they aren't.
Now, back to the GPIB commands. Looking at the GPIB section in the PTS
500 manual, it appears that it uses the command format that I expected.
For the extra .1 digit, just add one more digit in the 'F' command. So
where did I go wrong?
Seems the manual is not quite right in its examples. I was stringing
commands together like 'f1234567a0[LF]', the a0 being command for max
output level. That's what the manuals show in an example or two, but
seems the hardware gets confused if there is more that 1 command with
just 1 LF at the end. I think 'f1234567[LF]a0[LF]' is ok.
If I send it just 'f1234567[LF]' I get 123456.7 Hz, which is what I
expected. With 'f1234567a0[LF]' I get 1.234567 MHz. So it seems the
controller wants a LF after each command to not get confused.
There may be some finesse points I haven't worked out yet, but I'm on
the right track now.
I'm glad to hear you're getting it sorted and that sounds like a really
interesting unit, I'm quite jealous:-)
I hadn't expected the D310 to be anything more than two standard 310s in
the same box so that's another variant to add to the list.
Between PTS, Wavetek, and Rockland, there's a variety of units that throw
up some interesting similarities, although sometimes with subtle or not so
subtle differences , and then there are some quite different, such as the
PTS310 and the DDS version of the PTS160.
I bought one of the latter a while ago, without realising up front what it
was, only to have a small and so far unidentified daughter board, not
obviously part of the DDS board itself, detach itself in transit. I put that to
one side and never did investigate further, probably time I did, but the
PTS160 manual doesn't even acknowledge the existence of that version.
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