![](/images/new-backgrounds/1309981/30998115x1.webp)
Wirsri?rcddsrrninssthe~opwrtingdist.nCc
(where theDC voltage drop is the limiting factor). Ths following eqlutioas apply for a wndnctor sizeof #22 AWG.a minimwnuser station voltage of 18.0 volts, d a minimum power supply voltage as stated below.
For Modds PSlO, PSM, PS31, P M , PS60, usa Vmin =
28.4VDC:
(feet) P 322,181 | 1. | |
D h - | (mtgs)= 99,133 1Im (milliPmperes) |
For Models PS8, PSl5 (Vmin = 24.0 MC):
. .
(feet) = 185,874 1Im (rmllumpcrcs1
D h c e - (map) = 56,654 1I&# (milli.mpsrss)
Exnmpk: | Ths CM300URM300L with 25 ohm | |
~ u s a | r u p t o 6 0. . | . With a PS8 supply |
the maximum c p a h g ~ f o thisr anti011 is
185,874160 '' | = 3098 fkt (944 mstas). Asd |
with a | the muimomopsnting dishlLce |
| = 5370 feet (1652 mtgs). |
md a usa station with 25 ohm phollg (37mA) is 185,874EV = 5024 feet
Anotha bmsfit of not "earth" grounding the circuit return is tht it prevents the h t m h t i o n of noise through 'earth" curw(sfrom other equipmeat. If the RTS Systmes circuit
gmund~tsthsc~l~nts,itisWrdythattheywillbc
hevd is interfering noise on thed 4 o n line.
Wirin~lC&&g(See Cable Wiring D | i in Section 7, |
Application Momati011) |
|
Two c h m d 'TW' applications, or single c l l m l d , thma wiro a p p l i ~ & ~IMY~ USE ather e~ ~ C ~ O ~ I I O cableD C (for canrmimcs) or
is#2zgougswiroforinkm=&h. F o r y t
iumWi01u arch chtlmd should have m i~~J~wdually shieldedtwistalpirof.tlasr#2zgurgewirc;wrchis
8723 for 2 ~ b m n dUUCI~ , mn for 3 cbmnels. POX plenum md I or 2CV' C wiring, use Bddea 88723 md 88777. Thsplaaum able hna a slighUy smaller d*metcr, isTefbninsul.tsd, d.boutthree. timgthepriceof 8723
18777.
System circuit g r d should not b k t l y c o n d to | W i r e u s i n g c a b l e W i ~ , S e c t i o n 7 , t o r e d u c e | ||||
|
| intdemim UUCI help maintain a low crossc.1L f i p | |||
'euth'or'chssis'zmund(dirseclvmesnsacamectionmbstmea*. |
|
| |||
ohmmtawwld&). | ~ g C T 8 1 . l i o n i s b ~ t o |
|
| ||
its own chassis via a 0.1 microfaadcapacitor, stabli6biug |
| Liac levd is bchmwa 1OdBu md OdBu | |||
a r P d i o f i . q l l c I I c y ( R F ) ~ t o r a d u e s n d i o ~The audio a& | |||||
i n ~ c e f m m n d i o t n n s m i ~ . | (bchvecn 0.24 | .ad 0.77 volts rms). | Thwe levels are low | ||
~ t o ~ t ~ i n t o & e q u i p m m t ( s u e b a s | |||||
|
| ||||
To | of voltage acm(g tbe system ca- | TV amsns) yet high amugh to minimirs extend | |||
p l c i ~ , t h c p o w s r s u p p I y h s a b l s s d s r ~ t o c h . s s i s inmfemcetotheTWSpttm. |
| ||||
ground (22 kilohms). If the system hs no RTS Systems | The 200 ohm Liac i m p d a w is high enough to uUow | ||||
pow- supply, add a bleeder mistor at a cmotnl point in | |||||
the system. |
| mnnmmication om liae lengths of 1.6 kilometers (one | |||
| mile) d low mwgh to permit m d#lrule speech | ||||
|
| ||||
The benefit of not 'earth' gnnmdiug the RTS System | bmdwidth with 3.2 kilomttefs of d | a t e d cable. In | |||
most systems the 200 ohm impcdpace gives a high fidelity | |||||
circuit nzum is that continued operation is possible during | |||||
nn accidmtrl system ground fault. This awidmtal | bmndwidth with low lwsar. |
| |||
grounding uo happm whea a wire is pinched or a cable | When using equipmeat in nia or conditions of excessive | ||||
scraped.erossasbprpedge. Oncrceidentalgrwndcmb | |||||
moisturr, always protect the equipment with plastic covers | |||||
t o l d by the system until the fault can be cleared md | |||||
(with luck) b c f m a sccolld ground fnult can cause noise or | md make sure uU cable c~ll~ectcnsme lifted out of mud, |
overload or bring the system down. | mow or moisture md pmtected with plastic. Wpter mud | |
d s n o w i n ~ ~ ~ ~ c p n c a ~ s ~ n o i s e . | ||
|
Page 9