The H541 modulator
is a digitally tuned video modulator that converts
any baseband video and audio signal to a user-selected
UHF or Ultraband CATV channel. An internal
quartz crystal reference oscillator and
PLL circuitry ensure drift-free
performance.
The user
selects the output frequency
(channel) using the DIP switch
on the front panel. Any TV
connected to the output via
coax can receive the signal,
when tuned to the proper
channel.
ChannelPlus
Video Modulator
1
2
3
1) Hook from the top
2) Swing into place
3) push button to lock
OpenHouse modules attach from the top
tm
ChannelPlus model H616
Telephone Master Hub (4 lines x 6 phones)
Telephone Master Hub (4 lines x 6 phones)
Telephones
Telephones
From
Telco
From
Telco
RJ31X
RJ31X
Out
Expansion
Ports
Expansion
Ports
R
T
R
T
4
R
T
R
T
3
R
T
R
T
2
R
T
R
T
1
Televisions
+12vdc
Gnd
IR
Modulators
CATV
/Ant
A
B
+Pwr
High Headroom Amp w/IR Engine
350-086 power
supply (included)
LED glows when
power is applied
Up to 8 televisions
RG-6 Coaxial cable
Typical Installation
Things To Watch For:
Herringbone interference on modulator channel (diagonal lines):
Herringbone interference on many channels, including modulator channels
(disappears when you remove the CATV/antenna feed)
You may have chosen
a channel number that is not completely vacant. Distant UHF stations may not be watchable,
but will cause interference if you try to create a new channel at the same frequency. Also,
cable companies often have extra signals where there should be none. Try moving the
modulator channel to another number. You may have to add a low pass filter to remove the
cable company noise. If the filter does not work, try adding a DC-block to remove common
mode interference.
: The RF amplifier can be
overloaded by abnormally strong signals. Often, you can cure the problem with a simple
attenuator. Use a variable attenuator and try to find a signal level where the interference just
disappears. Sometimes, the problem is one station is far stronger than the rest. In this case,
attenuating all of the signals with a simple attenuator may cause the desired stations to be
weak (snowy). You must reduce the strength of the only offending station. A common FM trap
will help if the problem is a nearby FM tower. If the problem is a nearby TV station, often the
station management can provide suitable filters.
No picture
Weak ChannelPlus UHF channel
Audio volume is low
No color on ChannelPlus channels
… Verify that the video source is on and is producing a video signal. Check that
the TV and the modulator are tuned to the same channel. For example, if the modulator is
broadcasting on UHF channel 16, make sure the TV is on UHF 16 rather than CATV 16. UHF
16 and CATV 16 are at different frequencies.
… If the TV has a separate UHF input, be sure that it is
connected.
… The left and right audio inputs are combined for monaural. For
proper audio level, both right and left inputs must be used. If you have a mono source,
connect it to both right and left inputs using an RCA ‘Y’ connector.
… You may have chosen the incorrect cable standard.
Not all televisions can accommodate the 1.25MHz frequency difference between the H and I
cable standards. See the section on programming.
Coax Panel (Model H838HHR typical)
ChannelPlus
modelH541
Modulator
(single
channel)
Output
Sin
gle
Cha
nne
lDig
ital
Mod
ulato
r
Input
pllf
req
uen
cyc
ontr
ol
Video
Aud
ioL
Audio
R
Pow
er
Chan
nelS
elect
Output
Single Channel Digital Modulator
Power
Input
pll frequency control
Channel Select
Model H541
Video
Audio L Audio R
CCTV Camera
at front door
Video input
Audio inputs: Right and left
are combined for monaural.
Use the DIP switch to setup channel,
mode(UHF or Cable), system(std, irc
or hrc) and termination method.
14/65
15/66
16/67
17/68
18/69
19/70
20/71
21/72
22/73
23/74
24/75
25/76
26/77
27/78
28/79
29/80
30/81
31/82
32/83
33/84
34/85
35/86
36/87
37/88
38/89
39/90
40/91
41/92
42/93
43/94
44/100
45/101
46/102
47/103
48/104
49/105
50/106
51/107
52/108
53/109
54/110
55/111
56/112
57/113
58/114
59/115
60/116
61/117
62/118
63/119
64/120
65/121
66/122
67/123
68/124
UHF
69/125
UHF/CATV
IRC
HRC
LOOP
NORM
CATV
CATV
Specifications: typical @ 25 C ± 5 C
O
O
RF output
Power supply
performance
Video
Inputs
65-125
(excluding 95-99)
14-69
channel ranges
model number
signal/noise
55 dB
-60 dBC
+25 dBmV (85dBuV)
105-125 VAC
-45dBC @ 12MHz
300mA
15 VDC
differential phase
<4º
differential gain
L & R inputs combined for monaural
4%
audio
1 V rms @ 47k
video
UHF
350-086
CATV
standard
1 Vp-p @ 75
output level
input power
IM distortion
alternate channel
output voltage
output current
STD
CATV
Set the DIP switches from the following guide:
-Set desired mode:
UHF, CATV std, CATV irc or CATV hrc.
-Set channel:
Find the desired UHF or CATV channel and set.
-Set termination:
For normal operation (75 termination) select NORM.
When connecting video to a local monitor using a
‘Y’ adaptor set for LOOP (Hi-Z).
Programming the H541
Programming Examples
UHF channel 23, normal termination (75 )
Cable channel 116 (standard), loop through termination (Hi-Z)
UHF channel 65, normal termination (75 )
Cable channel 65 (HRC), normal termination (75 )
>1M in loop through mode (LOOP)
75 in normal mode (NORM)
video termination
(switch selectable)
DECLARATION OF CONFORMITY
THIS DEVICE COMPLIES WITH PART 15 OF THE FCC RULES. OPERATION IS SUBJECT
TO THE FOLLOWING TWO CONDITIONS: (1) THIS DEVICE MAY NOT CAUSE HARMFUL
INTERFERENCE, AND (2) THIS DEVICE MUST ACCEPT ANY INTERFERENCE
RECEIVED, INCLUDING INTERFERENCE THAT MAY CAUSE UNDESIRED OPERATION.
FCC classifies this product under part 15 of its rules as a “television interface device”.
Systems designed using television interface devices have the following legal requirements:
1) The modulated channel signal strength may not exceed 15.56dBmV at any television.
2) If an antenna is used in the system, the modulated channel signal strength may not exceed
-51dBmV at the antenna input port.
The system you design must comply with these regulations. As the installer, you are
responsible. The easiest way to be fully compliant is to use a ChannelPlus coax panel.
ChannelPlus panels have the necessary isolation from the modulator input ports to the
antenna input port and gain characteristic from the modulator input ports to the television
output ports. These features will make your modulator comply with the above requirements.
The
shown above is fully compliant.
Installation requirements:
For the Installer:
Federal Regulation 47CFR15.115(b)(1)(i).
Federal Regulation 47CFR15.115(c)(4).
Typical Installation
