3 use a simple resistive mixer. The values should not be critical unless
you're running the signal long distances after mixing 33 ohms from each
modulator and direct from the junction to the output should work ok



Video modulators need a far greater bandwidth between channels as the
sideband/s are not limited, you will NOT be able to use 6Meg, 10Meg
between channels is probably a good figure.

-----Original Message-----
From: pic microcontroller discussion list
[mailto:PICLIST@MITVMA.MIT.EDU] On Behalf Of Lee Mason
Sent: 10 March 2002 10:53
To: PICLIST@MITVMA.MIT.EDU
Subject: Re: [EE]:Multi-video to RF converter

If the modulators are not on the same channel then I think the problem
is a
feature of the modulator, it is a "off through" type. This type of
modulator
will only allow rf to pass through when the power is removed, this is to
prevent interference from external RF on the
same channel.

Two ways to fix this
1 Find the pin diodes that are shorting the input when the power is
applied
and remove them

2 Get a "mixed boost" modulator.

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