# Coax cable splitter - joiner question



## Chandu

Hi there, here is a configuration question.

*Short version:* Can a coax cable splitter be used inversly as a combiner/joiner of signal from 2 coax inputs and a combined coax output, without risking damage to equipment?

*Long version with explanation and motivation behind the question:*

I have a standalone HD monitor hooked up to an ATSC tuner and an indoor amplified antenna. The hookup into ATSC tuner from the antenna is with a standard 75 ohm coax input. (Attaching an external antenna on the roof etc. is not an option, due to variety of reasons not worth describing here.) I'm in San Francisco Bay area, where I get signals from 2 major towers from 2 opposite directions: San Francisco and San Jose.

Everything is working great with my configuration except for a caveat described below. I'm able to get very good signal strength (in the range of 80+) from all channels listed by antennaweb.org for my location. The caveat is that I get San Francisco channels in the clear if I orient my antenna one way, but no San Jose channels. Vice versa, I get San Jose in the clear if I orient the antenna another way, but no San Francisco channels. Since the strength of the indoor antenna is not in question and I have no motivation to install an outdoor antenna, I decided to solve the problem by buying an additional indoor antenna. I wish to join 2 indoor antennae, each with dedicated orientation for 2 locations.

My specific question is about joining the signal from 2 indoor antennae. I'm looking for something with 2 coax female inputs and 1 coax male output. I had bought a good quality coax cable splitter a while back, for completely different reason which isn't applicable anymore. Since it's lying around, I thought about inverting it as a joiner instead. I wanted to find out if such inversion is even possible. I didn't want to experiment myself and risk damaging the tuner. (I understand I'll need to add male-to-female or female-to-male coax converters at each end, but that's a minor point.)


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## Jim5506

Your splitter has all female connections, just use a short piece of cable to attach the output to your tuner and run the two antennas into the splitter. your only problem may be multipath, but try it, if it works great, if not, we have learned something.


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## Chandu

Jim5506 said:


> Your splitter has all female connections, just use a short piece of cable to attach the output to your tuner and run the two antennas into the splitter.


Yeah, sorry about the minor gaffe, inattention to detail. :lol: Thanks.

Anyhow, I completed my experiment with a bit of trepidation about my tuner's health. And lo and belold, I'm very happy to annouce that it has been a resounding success!! Without any funky outdoor antenna setup I'm now getting all digital channels in my area in the yellow region with signal strength in the orders of 80-90+. I'm also getting one digital channel in the dark green region with 65-70 strength. I'm getting absolutely nothing in the light green, red, blue or violet region. But I don't care to.

I haven't done any tests with NTSC tuning, because I don't care to. For every single NTSC channel in the yellow region in my area, there is an ATSC equivalent. There is no NTSC capability in the external tuner. It is there in the HD monitor itself. If I have more time on my hands later on, I may play with it just for reference.

So encouragingly, I had no multipath problems. I did some research on multipath, and they always talk about ghosting in pictures. Is the ghosting specific only for NTSC channels? I thought with ATSC signals, you either get the channel or you don't. With a weaker ATSC signal, you sometimes get screen breakup, partial freeze etc. But does multipath manifest with ATSC signals as ghosting at all?

I'll try to document details about every compoent in my configuration a little later. Hopefully, it will be helpful as a reference to someone if they're interested in an experiment like mine.


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## BornToFish

Digital signals will not display as ghosting. All interference in relation to a digital signal will cause either pixelization, or loss of signals. A bouncy signal usually indicates there is some of this taking place.>BornToFish


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## Chandu

Chandu said:


> I'll try to document details about every compoent in my configuration a little later. Hopefully, it will be helpful as a reference to someone if they're interested in an experiment like mine.


It has been a while since I posted this. But if it helps someone else, here is what all I did with my setup:

ATSC tuner: DigitalStream ProBand HD3150 Plus

2 indoor antennas used:

RCA ANT525 - high performance amplified HDTV antenna (amplifier turned on)
Radio Shack amplified Signal Finder indoor TV antenna

Coax cable joiner/splitter from Monster Cable 5-1000 MHz

Radio Shack In-Line 75 ohm 6dB attenuator (I had to put this between the cable joiner and the ATSC tuner. This is because the signals from the closest and strongest stations were coming in too strongly with 2 amplified antennas combined, and blanking out the tuner.)


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