Multiplex Technology 3445, 3425 Changing modulation standards, Common questions, Models available

This ChannelPlus 3400 Series video distribution system contains digitally-tuned video modulators that convert 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 "select" button to choose which modulator and the "program" button to enter the number of the desired channel. Any TV connected to the output via coax can receive the signals, when the TV is tuned to the proper channel.

Models available:

3425 2 channel system

3445 4 channel system

Controls and Connections - Model 3445 shown

			®								A B C D
				model 3445 four channel integrated modulator and distribution system		D			B
					OUTPUT	CH			CH		Remove jumper for Hi-Z
											(See manual)
			select	program	POWER	C			A
A	B	C	D		15VDC	CH			CH
				pll frequency control	600mA
						VIDEO	AUDIO L	AUDIO R	VIDEO	AUDIO L	AUDIO R

Changing modulation standards

Cable HRC and IRC considerations

Most cable services use IRC frequency assignments. This is the default for the ChannelPlus 3400 series’ modulators. However, if the cable service uses HRC or the TV appears to search for the "house channels," the modulator can be reprogrammed to use HRC assignments by entering the number “ 98”. Set to IRC by entering a “99”. Both of these settings are only used for setting HRC/IRC. Note: This setting can be entered on any modulator channel, A, B, C, or D, and affects all channel assignments for that unit. Cable channels must either be all IRC or all HRC.

Common questions

Can an amplifier be used on an output to drive signals over longer cable paths? … No.

The IR remote control feature will be defeated if an external amplifier is used.

Can a splitter be used on one or more outputs in order to add more TVs? … No. The model 3425/3445 Multi-room Video Distribution System is a pre-engineered system providing optimum signal levels to each TV for clear, crisp picture quality. Each time a splitter is added, there is lowering of signal level called insertion loss. Insertion losses upset system performance. Additionally, the IR remote control feature will be defeated.

To hang with connectors on the side

Program button enters the channel number

Select button chooses the modulator.

Modulator LEDs show which modulator is selected

RF output

Power supply 15VDC 600mA

Video inputs

Audio inputs: Right and Left

Terminating jumpers (remove for hi-Z)

To hang with connectors on the bottom or top

Mounting hole template

Specifications: typical @ 25OC ± 5OC

3400 Series

Inputs	video	1 Vp-p @ 75
	audio	1 Vrms @ 47K
		L & R inputs combined for monaural
Video	differential gain	4%

Option:			A B C D
To connect the video and audio to a local monitor, use RCA type
‘Y’ adaptors and remove the ’LOOP’ jumper for this channel.
	AUDIO R	AUDIO L
VIDEO
	Model 3245/3445 - RF section
Modulator Section	INPUTS AB+Pwr MODULATORS	OUTPUTS ToTVs	For use with model
			2133	INPUT Ant/ CATV
Connection for			distribution panel
(Requires coax cable,
RG-6 recommended)
Expansion input			}
for other modulators
(25dBmV max)

Outputs for TVs (8)

Input for cable or antenna

performance	differential phase		<4º
	signal/noise		55 dB
RF output	standard	UHF		CATV
	channel ranges	14-64		65-125
				(excluding 95-99)
	output level	+15 dBmV (75dBµV)
	IM distortion		-60 dBC
	alternate channel	-45dBC @ 12MHz
	Gain CATV/Ant to output		0 dB
Power supply	model number	350-079
(UL listed)	output current		600mA
	output voltage	15 VDC
	input power	105-125 VAC
	power consumption	<9 watts
Physical	modulator section	1.5x7.9x5.5“	(3.8x20.0x14.1cm)
		2 lbs 10 oz (1.19kg)
	RF section	0.9x6.3x2.5“ (2.4x16x6.4cm)
		1 lbs 2 oz (0.5kg)

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