Electroline Multicoupler

[rocky28965]

Looking at a couple of Electroline Multicouplers on Amazon.
For VHF/UHF

EDA2500MMA 4 Port
EDA2900MMA 8 Port

Other than the number of ports, is one better than the other?

 

[dave3825]

Watching. I use a 2800 8 port and am happy with it.

Quite a few others use the same one .

Here are threads on Electroline Search results for query: Electroline

 

[KevinC]

The 4 ports have a lot of gain. Sometimes too much gain is a bad thing.

 

[Ubbe]

Both their 4 and 8 port models has 0-3dB gain and a flat EQ curve. Not more gain at VHF and much lesser at high UHF as most other amplifiers. But to fully compensate for coax loss it could have more gain at UHF and lesser at VHF.

The not so good spec are the internal noise figure. " 8 dB typical noise figure for the complete product, from input to amplified output"

It's an active splitter intended for already amplified signals or already strong signals, like a Stridsberg multicoupler. For weak signal monitoring it needs a pre-amplifier with low noise NF spec and high signal capability without creating intermod and preferable mounted at the antenna and with a EQ that lowers the gain at lower frequencies.

/Ubbe

 

[KevinC]

Both their 4 and 8 port models has 0-3dB gain and a flat EQ curve.

/Ubbe

So they do. This is a departure from their previous lines of drop-amps.

 

[rocky28965]

Thanks guys.
I bought the 4 port one.
8 port dosent seem to be available atm.

 

[rocky28965]

One of the pictures of this item on Amazon, shows a power adaptor, so I assume it's included.
No mention of a cable.
Connections appear to be F type or SMA.
Could someone confirm please.

 

[dave3825]

Runs off a wall wart that has type F connectors and uses regular coax.

 

[rocky28965]

I guess I'll have to get a bunch of F connectors.

 

[rocky28965]

I'll just give this thread another tug.

I have got the EDA2500MMA.

I bought this from Amazon Australia, thinking it would come with a NZ/AU power supply.
Wrong, it came through Amazon US & had the US type.
I tried it with a NZ adaptor but it wont work on our 240 volt system.

The specs says 15 Volt DC 350 mA
I'm currently running it on a 13.8 Volt 750 mA Uniden power supply.
Seems happy enough with that atm.

Doing a search for a one with the correct specs.
15 Volt DC 1.0 Amp are readily available.

Question:
Would that be too much for it or should I keep looking?

 

[Ubbe]

You can run it on 12V and even lower. The 15V spec are probably because satellite boxes sends out 15V on the coax. It takes maximum 350mA so anything at that ampere or higher will work.

/Ubbe

 

[rocky28965]

Thank you, that makes it a bit easier.

 

[rocky28965]

Is it normal for this device to run a little warm?

 

[kruser]

Is it normal for this device to run a little warm?

Yes

 

[dave3825]

Yes, there are powered electronics in a sealed case without any ventilation.

 

[rocky28965]

Thank you, I thought that would be the case, just wanted to make sure.

 

[acj76]

I just picked up an Electroline 2802. Bear with me as I'm still new to this...
I'm finding that it splits the signal ok, but the noise increases quite a bit and the noise floor bounces, overall it sounds worse. Here is a picture of the signal from an SDR connected directly to the antenna:



Here it is alone through the 2802:


I've been searching the forums for information about it. Would putting terminator caps on the unused ports reduce the noise? Or running the power to a different outlet or something? I know a lot of you have had success using these amps, clearly I'm missing something. Thanks in advance for the help, or pointing to the help.

 

[Ubbe]

The noise floor seems to be at -68dBFS in both pictures. The signal from the transmitters differ, some are the same level and some are weaker. You probably have automatic gain configured for RF or IF and don't use fixed gain values. You can see that without the Electroline you have signal variations in the history spectrum for the noise floor that seems to indicate a pulsating signal, a control channel idle data that transmit a burst and then waits twice the time and then a burst again, or a pager transmitter doing the same.

With the Electroline, that are a zero gain splitter, the AGC action of the SDR receiver are more evident. I suggest to set fixed gain values to both RF and IF and try again. It might be that the Electroline are actually having a 3dB gain, when not loading unused ports, but isn't a bad thing but the AGC in the SDR are then more active on the higher signal level from that pulsating transmitter, that might not show in that narrow frequency bandwidth spectrum display.

/Ubbe

 

[prcguy]

I just picked up an Electroline 2802. Bear with me as I'm still new to this...
I'm finding that it splits the signal ok, but the noise increases quite a bit and the noise floor bounces, overall it sounds worse. Here is a picture of the signal from an SDR connected directly to the antenna:
View attachment 163727


Here it is alone through the 2802:
View attachment 163728

I've been searching the forums for information about it. Would putting terminator caps on the unused ports reduce the noise? Or running the power to a different outlet or something? I know a lot of you have had success using these amps, clearly I'm missing something. Thanks in advance for the help, or pointing to the help.

Welcome to the new world of using the wrong thing for your needs. Your CATV drop amp/splitter is doing exactly as it should in many cases. A CATV drop amp is designed for a closed cable system fed with a known number of signals at known levels (like a maximum of 77 cable TV channels) which would work within its design specs. Connect a CATV drop amp to an antenna with nearly unlimited signals at levels all over the map and you get exactly what you posted due to the very high noise figure and low signal handling properties forcing the amplifier into overload and distortion land.

CATV drop amps were never designed to be used to amplify off air TV signals, let alone broad band high level signals off a scanner antenna. It’s not the right thing for the job.

 

[acj76]

I suggest to set fixed gain values to both RF and IF and try again.

I had all AGC off, as far as I could tell, and the manual gain level pretty high. All settings the same in both pictures. I played around with the gains, but it had little effect to make it sound any better. I should also say my whole set up is in a pretty RF noisy area: laptop, extra monitor, USB sound card, mini sound mixer, desktop speakers, scanner, SDR, all plugged into a nearby big power strip with about a half dozen transformer plugs on it.

Welcome to the new world of using the wrong thing for your needs.

Yeah, I knew they're for CATV, just trying to save a buck over the Stridsberg I was looking at. I read that many people have had luck with the Electrolines, so I decided to give it a try. I may end up getting the Stridsberg in the end, and the rest is a lesson learned.