I'm in the process of having a house built. While everything was open, I ran 50' of LMR from the attic to my bedroom. My question is can I use a Stridesburg MCA 204M in reverse as a diplexer/triplexer to feed a MCA208M? Thanks
I know this has been ask before but......
- Thread starter JamesBrox
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NO.
Ubbe
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If you don't have the money or space to have several LMR coaxes then at least add several RG6 for low VHF and high VHF. It's usually a lot more flexible to have access to several antennas down at the scanners. Then you can split or combine as you wish or have some antennas direct coupled to a single scanner without any filters. Usually one antenna can receive more or less all frequency bands and sometimes a VHF antenna receives UHF frequencies better than a UHF antenna depending of its location on the roof and how much of interferences it receives.
If you only want one coax then you'll have to look at those ham radio diplexers or triplexers to combine different frequency band antennas into one coax. Your 4-port 204M can split one 800MHz antenna and you then probably don't need a 8-port but another 4-port splitter for a discone type of antenna, and you can have a diplexer or triplexer to combine the 204M outputs and even include another antenna coax to feed all antenna signals to be used with scanners that needs to scan all frequencies. There's all kind of possibilities as long as you have that antenna signal going down to your scanners using its own coax.
/Ubbe
If you only want one coax then you'll have to look at those ham radio diplexers or triplexers to combine different frequency band antennas into one coax. Your 4-port 204M can split one 800MHz antenna and you then probably don't need a 8-port but another 4-port splitter for a discone type of antenna, and you can have a diplexer or triplexer to combine the 204M outputs and even include another antenna coax to feed all antenna signals to be used with scanners that needs to scan all frequencies. There's all kind of possibilities as long as you have that antenna signal going down to your scanners using its own coax.
/Ubbe
Edit: I misread the original post, a diplexer or triplexer is what you need, not a multicoupler...
We even had a 204 in the attic feeding separate 208's in different rooms, that worked great.
More recently I have had a 204 feed two 208's and a 204 in my cabinet to allow 20 scanners (21 if you use the 4th port on the first 204) off one antenna.
I also used Stridsberg's suggestion of an un-amplified splitter feeding two amplified multicouplers. That also worked very well, I could not see any difference in listening quality.
Stridsberg also sells a 16-port multicoupler (MCA216M VHF/UHF Receiver Multicoupler| Scanner Master). They are expensive however. It might be more cost effective to buy them separately, especially if you already have one or more.
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Ubbe
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What it really boils down to are what signal levels are used for monitoring. People who can use a paperclip to receive everything they want to monitor can use anything to split signals and amplify as long as it doesn't overload a scanner. Those cheap TV amplifiers with 4 or 8 outputs will then work fine. Even a single output TV amplifier that has a gain of 15-20dB and bad noise figures will work if a passive 1-8 splitter are used as that will attenuate sufficient to be able to be used.
If you really are into weak signal monitoring then you will need to get a low noise and probably strong signal capable amplifier, something that Stridsberg can't supply, and use your own splitter and preferable a variable attenuator to exactly set the correct signal level. It will cost less than a Stridsberg but will have better specifications and will also improve things even more if the amplifier are installed at the antenna.
/Ubbe
If you really are into weak signal monitoring then you will need to get a low noise and probably strong signal capable amplifier, something that Stridsberg can't supply, and use your own splitter and preferable a variable attenuator to exactly set the correct signal level. It will cost less than a Stridsberg but will have better specifications and will also improve things even more if the amplifier are installed at the antenna.
/Ubbe
What I'm reading is using an active multicoupler in reverse as a diplexer or triplexer to possibly bring in different frequency bands to one coax. This can't work because the amplifier in the multicoupler is pointing the wrong way for this, it wants to bring in one cable, amplify, then split to four.
If you need to feed more outputs than a multicoupler has, instead of adding another multicoupler downstream its best to use a single amplifier in the system with enough gain to feed passive splitters downstream. An amplifier with 20dB of gain will easily feed an 8-way divider feeding eight more 8-way dividers off each port for a total of 64 receivers. Or a 4-way feeding more 4-ways feeding another set of 4-ways.
An amplifier like the MiniCircuits ZHL-2010 covers 50-1000MHz, 20dB gain with about the same noise figure of a Stridesberg but way better signal handling and overload avoiding specs. Then use passive splitters throughout the system with a few attenuators to balance gain where needed. If you place the amplifier in the attic near the antenna you will be even more ahead of the game improving noise figure and signal to noise ratio.
For the OP, if you need to combine antennas or signals of different frequency ranges ahead of a multicoupler then use a passive low loss diplexer or triplexer.
If you need to feed more outputs than a multicoupler has, instead of adding another multicoupler downstream its best to use a single amplifier in the system with enough gain to feed passive splitters downstream. An amplifier with 20dB of gain will easily feed an 8-way divider feeding eight more 8-way dividers off each port for a total of 64 receivers. Or a 4-way feeding more 4-ways feeding another set of 4-ways.
An amplifier like the MiniCircuits ZHL-2010 covers 50-1000MHz, 20dB gain with about the same noise figure of a Stridesberg but way better signal handling and overload avoiding specs. Then use passive splitters throughout the system with a few attenuators to balance gain where needed. If you place the amplifier in the attic near the antenna you will be even more ahead of the game improving noise figure and signal to noise ratio.
For the OP, if you need to combine antennas or signals of different frequency ranges ahead of a multicoupler then use a passive low loss diplexer or triplexer.
Yeah, I missed that. I read it as splitting one antenna to multiple multicouplers, my bad!
prcguy is correct, use a true diplexer or triplexer to combine multiple antennas to one coax.
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Like I said "NO" to the original post. I had to read it more than once before I posted my reply - his use of the word "reverse" is the main clue and of course an active multicoupler can not work in "reverse". I was in a hurry so just said "NO".
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