TriPoint VertexRSI 7200, Руководство по эксплуатации и обслуживанию

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A /D C ARD C ALIBRA TIO N
D - 1
A PP END I X D - A/D CA R D CA L I B R AT I ON P R OCEDU R E
1.0 I nt r odu c t i on
Th i s append i x conta i ns i nstruct i ons for ca li brat i ng/reca li brat i ng the A /D card of the
7 2 0 0 A C U. A ca li brat i on procedure i s norma ll y performed at the factory as part of
the product conf i gurat i on. A f i e l d reca li brat i on shou l d on l y be necessary i f
operat i ona l prob l ems (norma ll y due to dr i ft) are i ncurred, or i f d i fferent v i deo
rece i vers are used i n the A G C mode.
The fo ll o w i ng equ i pment i s requ i red:
1 D i g i ta l Mu l t i meter (D M M), 3.5 d i g i ts
1 D C vo l tage source, ad j ustab l e, 0 V D C to + 1 0 V D C
1 tr i mmer ad j ustment too l
For an A G C mode rea li gnment ( i .e., for a d i fferent or ne w rece i ver), proceed to
paragraph 3.0.
If perform i ng a fu ll ( li near and A G C) rea li gnment, fo ll o w the steps i n paragraphs 2.0
and 3.0.
Open the 7 2 0 0 A C U by remov i ng the four # 6-3 2 scre w s ho l d i ng the front of the
top li d and s w i ng the li d i nto a l ocked pos i t i on. Locate the 8 0 0 2 2 1 assemb l y,
norma ll y found on top of the I/O card (8 0 0 2 5 2).
If one or both of the channe l s i s conf i gured for A G C mode (JP1/2 are i n pos i t i on
" A) then po w er do w n the un i t, note the channe l conf i gurat i on and p l ace a ll j umpers
i nto the " B " pos i t i on.
Po w er up the un i t and proceed w i th the ca li brat i on.
2.0 A/D Conv e r t e r L i n ea r Offs e t Ad j ustm e nt
1. Connect the D C vo l tage source to the i nput term i na l s of the back of the 7 2 0 0
A C U for both channe l 1 and channe l 2.
2. Connect the D M M across the D C vo l tage source and ad j ust the vo l tage source
so that the D M M i nd i cates 5.0 0 V D C.
3. On the 7 2 0 0 A C U M a i n m e nu , se l ect D i sp l a y syst e m st a tus... , and A/D
st a t e s .