16-port Stridsberg Multicoupler

[N9JIG]

Stridsberg now sells a 16-port active multicoupler, the MCA216M. Interestingly it has an "N" connector for the input paired with the 16 BNC connectors on the outputs. It is very expensive ($845.00) so might be out of reach for many, including me currently.

Stridsberg's web page also suggests that using a passive multicoupler paired with multiple active multicouplers would provide a similar effect. Pairing 2 MCA208M's with a MC202 passive multicoupler would cost $745.00 so one could save $100 if you were willing to deal with 3 units instead of one.

I am thinking of trying to convince the wife to let me get one of the new 16-port units but I think that might be a hard sell as the two 8-ports fed from a 4-port unit are working out pretty well for me now. Maybe if I am a good boy she will relent.

 

[mass-man]

Christmas isn't far off!!!!!

 

[buddrousa]

We have the same setup almost.
Most of the time my antenna runs to a 4 port feeding a 4 port on a 4 scanner rack and 2 ports feeding 2 8 ports in my 16 scanner rack and the last port feeding my desktop for a SDS100 ect.

 

[prcguy]

The Stridesberg 16 port has similar specs to the other models with a 1dB compression point of 17dBm and an IP3 of 32dBm. Those are mediocre at best and would not work at my house without creating lots of IMD within the amplifier inside the multicoupler. The price on that model is ludicrous for what you get.

You can do much better making your own with a MiniCircuits ZHL-2010 amplifier with a 1dB compression of 26dBm and an IP3 of 46dBm for $170 and a MiniCircuits ZC16PD-222-S 16-way divider that covers 10 to 2200MHz for $347.95. That's $518 worth of goods and even after putting them in a box with BNC connectors and interface cables you would be cheaper than the Stridesberg with waaaay better specs.

You can sometimes pick up the parts on Ebay for much better prices, I just got a ZHL-2010 amplifier this week for $34.99 and I've got another in the past for a similar price along with the lower gain version ZHL-1010.

 

[kruser]

You can do much better making your own with a MiniCircuits ZHL-2010 amplifier with a 1dB compression of 26dBm and an IP3 of 46dBm for $170 and a MiniCircuits ZC16PD-222-S 16-way divider that covers 10 to 2200MHz for $347.95. That's $518 worth of goods and even after putting them in a box with BNC connectors and interface cables you would be cheaper than the Stridesberg with waaaay better specs.

The 16 port MiniCircuits divider is perfect but what about a similar amp but one that will go down to 30 MHz or lower.
Any suggestions for a similar amp with similar IP3 but able to operate down to 30 MHz? The upper end needs to be 1 GHz minimum and the higher, the better.

I'd bet the ZHL-2010 will pass frequencies below 50 MHz but they don't show a derating curve below 50 MHz so it's unclear as to what values may be expected.
If you have done any testing below 50 MHz with a ZHL-2010, please post your findings!

This setup looks near perfect for my needs.

 

[dlwtrunked]

The 16 port MiniCircuits divider is perfect but what about a similar amp but one that will go down to 30 MHz or lower.
Any suggestions for a similar amp with similar IP3 but able to operate down to 30 MHz? The upper end needs to be 1 GHz minimum and the higher, the better.

I'd bet the ZHL-2010 will pass frequencies below 50 MHz but they don't show a derating curve below 50 MHz so it's unclear as to what values may be expected.
If you have done any testing below 50 MHz with a ZHL-2010, please post your findings!

This setup looks near perfect for my needs.

The ZHL-2010 has too high a noise figure to be good and with that much loss with the 16 port divider, not enough gain to make use of a lower noise figure if the ZHL-2010 had one.

 

[Ubbe]

Stridsberg have a noise figure of 3,5dB in their multicouplers and preamplifiers. The ZHL-2010 have 3,7dB.

When you put a seperate preamplifier at the antenna and have splitters down at the receivers the whole coax attenuation and the impedance match isolation between antenna and coax will give you a lot better noise figure in the system. If the coax attenuate 3dB you improve the NF by 3dB and any variation of the antennas impedance over its frequency range, that will create mismatch to the coax, are totally eliminated. You will receive a lot better signal that way. And if you do not have as severe interference problem as prcguy you could use a more low noise preamp like less than NF1dB that will improve your reception even more. The little loss you could get when using $20 CATV 75 ohm 1-8 splitters are compensated for many times over by the remote preamp installation. And if you don't already use high grade coax like LMR400 you can then instead use RG6 and save a huge amount of money in your antenna system that will have higher performance than Stridsbergs at almost 1/10 of the cost.

/Ubbe

 

[prcguy]

A lower noise figure would be nice but 3.5dB is ok and similar to other preamps that will fold under much lower signal conditions than the ZHL-1010 or ZHL-2010. You can't get a lower noise figure and have high signal handling and wide band width at the same time, it just doesn't exist.

If this was a filtered system where you were only taking a few MHz of spectrum like the marine band only or the VHF air band only and filtering everything else out before the preamp, then you can use a lower IP1/IP3 preamp with perhaps a .5dB noise figure. But then a several MHz wide filter with good skirts are going to have 1 to 2dB loss, so your system noise figure will be up to 2.5dB right out of the gate.

The ZHL-2010 has too high a noise figure to be good and with that much loss with the 16 port divider, not enough gain to make use of a lower noise figure if the ZHL-2010 had one.

 

[prcguy]

I have not tried the ZHL amps below about 118MHz, so I don't know how they perform there. In my tower top filtered amplified system I diplex in a VHF lo band antenna with no amplifier after the VHF/UHF preamps. I only have a two way splitter in line ocasionally, so there is very little loss at VHF lo in my system.

If you need VHF lo I would propose a dedicated antenna and band pass filter or at least a low pass filter, then choose an amplifier with good specs for lo band and diplex that into your VHF/UHF line.

The 16 port MiniCircuits divider is perfect but what about a similar amp but one that will go down to 30 MHz or lower.
Any suggestions for a similar amp with similar IP3 but able to operate down to 30 MHz? The upper end needs to be 1 GHz minimum and the higher, the better.

I'd bet the ZHL-2010 will pass frequencies below 50 MHz but they don't show a derating curve below 50 MHz so it's unclear as to what values may be expected.
If you have done any testing below 50 MHz with a ZHL-2010, please post your findings!

This setup looks near perfect for my needs.

 

[kruser]

I have not tried the ZHL amps below about 118MHz, so I don't know how they perform there. In my tower top filtered amplified system I diplex in a VHF lo band antenna with no amplifier after the VHF/UHF preamps. I only have a two way splitter in line ocasionally, so there is very little loss at VHF lo in my system.

If you need VHF lo I would propose a dedicated antenna and band pass filter or at least a low pass filter, then choose an amplifier with good specs for lo band and diplex that into your VHF/UHF line.

Thanks!

Since I'd posted my question, I was thinking exactly as you regarding diplexing in the VHF low stuff. I realized I should have everything I need to do it already so I may go this route. Even better, a dedicated VHF low band antenna setup hooked to a couple select radios.

I already have 8 port Stridsberg couplers on a couple antennas but the ports are all used so I'd need to daisy chain to gain more ports. That's something I'm not fond of. I've tried it before with the Stridsberg couplers and ended up with bad mixing or overload problems.
I'm also in a very dense RF environment here so I must work hard and bulletproof everything before the signals ever get to the radios using a mix of notch and bandpass filtering.

 

[dlwtrunked]

A lower noise figure would be nice but 3.5dB is ok and similar to other preamps that will fold under much lower signal conditions than the ZHL-1010 or ZHL-2010. You can't get a lower noise figure and have high signal handling and wide band width at the same time, it just doesn't exist.

If this was a filtered system where you were only taking a few MHz of spectrum like the marine band only or the VHF air band only and filtering everything else out before the pre-amp, then you can use a lower IP1/IP3 pre-amp with perhaps a .5dB noise figure. But then a several MHz wide filter with good skirts are going to have 1 to 2dB loss, so your system noise figure will be up to 2.5dB right out of the gate.

If you are not trying to improve your reception on the scanner, 3.5 dB is OK but but one can do better..
"You can't get a lower noise figure and have high signal handling and wide band width at the same time, it just doesn't exist."
True, if you are in such environments and not willing to spend money on filtering out the problems. I use filters followed by a pre-amp followed by Stridssburg. I do have an FM broadcast and country 800 MHz services tower at 0.8 fmiles form me and another FM broadcast stations at 3 miles. That works better than anything else I have tried--and I regularly try all sorts of configurations. The 100 MHz-1400 MHz pre-amp I usually use is this one (anbd I have used it down to 6 meters though I do not know the gain there):

http://rfbayinc.com/products_pdf/product_87.pdf

(Amazon's price is $220, and eBay about the same, but I have sometimes found it at half that.) From experience in comparing, I no longer consider any pre-maps with NF over 2 and always check the IP.
I have two good FM broadcast band blocks and used to have a VHF notch filter form PAR to notch out the FD repeater (now on 800 MHz). The only problem now is sometimes from the local 2m repeater on the same tower and I insert a filter if tuning to something where that is a problem. Generally, I check the spectrum with a spectrum analyzer and also SDRs to make sure I am not missing a problem. But any setup is location dependent.

 

[prcguy]

A very high level preamp like the ZHL series is a generic solution, but if you have a spectrum analyzer to identify problem frequencies or bands, you can then measure the spectrum and design a specific antenna front end system using band pass/band reject filters and better noise figure, lower IP1/IP3 amplifiers. Most people are not capable of doing that.

If you are not trying to improve your reception on the scanner, 3.5 dB is OK but but one can do better..
"You can't get a lower noise figure and have high signal handling and wide band width at the same time, it just doesn't exist."
True, if you are in such environments and not willing to spend money on filtering out the problems. I use filters followed by a pre-amp followed by Stridssburg. I do have an FM broadcast and country 800 MHz services tower at 0.8 fmiles form me and another FM broadcast stations at 3 miles. That works better than anything else I have tried--and I regularly try all sorts of configurations. The 100 MHz-1400 MHz pre-amp I usually use is this one (anbd I have used it down to 6 meters though I do not know the gain there):

http://rfbayinc.com/products_pdf/product_87.pdf

(Amazon's price is $220, and eBay about the same, but I have sometimes found it at half that.) From experience in comparing, I no longer consider any pre-maps with NF over 2 and always check the IP.
I have two good FM broadcast band blocks and used to have a VHF notch filter form PAR to notch out the FD repeater (now on 800 MHz). The only problem now is sometimes from the local 2m repeater on the same tower and I insert a filter if tuning to something where that is a problem. Generally, I check the spectrum with a spectrum analyzer and also SDRs to make sure I am not missing a problem. But any setup is location dependent.

 

[Ubbe]

I've been using a $200 Stridsberg multicoupler on and off over the years and had it feeding 4 scanners. Then I replaced it with a $25 PGA 103+ amplifier and a $15 CATV 1-6 splitter and the 3dB lower noise figure alone gave a big improvement. It's like doubling the signal, stacking two antennas or making a yagi antenna twice as long. If I had any coax attenuation it would have helped even more if the amplifier where moved to the antenna. If you don't mind using DIY modules you can save some money and still improve over the plug&play boxes.

/Ubbe

 

[ScannerDude244]

I've been using a $200 Stridsberg multicoupler on and off over the years and had it feeding 4 scanners. Then I replaced it with a $25 PGA 103+ amplifier and a $15 CATV 1-6 splitter and the 3dB lower noise figure alone gave a big improvement. It's like doubling the signal, stacking two antennas or making a yagi antenna twice as long. If I had any coax attenuation it would have helped even more if the amplifier where moved to the antenna. If you don't mind using DIY modules you can save some money and still improve over the plug&play boxes.

/Ubbe

You have any pics of that setup?

 

[N9JIG]

For the normal(*) scanner listener with a lot of scanners the Stridsberg solution is the easiest way to connect all those scanners to a single antenna and achieve good results, basically as good as he would get with that same antenna connected directly to the scanner. While somewhat better (if not measurable by mere mortals) performance might be had with less expensive but more complicated to build solutions like the separate devices spoken of there is something to be said for the ease of use and all-in-one device like a Stridberg.

All that said, I am thinking of building a similar solution to replace my multiple Stridsbergs in my cabinet. I have a convenient board to mount the dividers, pre-amps and power supplies to and all those components would be out of sight and protected. I would like to put the amp up at the antenna however, away from the computers and other noise generators in the house.

* as normal as one can be with 16 scanners.

 

[Ubbe]

While somewhat better (if not measurable by mere mortals)

It's not needed to measure, you can directly hear the difference from the 3dB better signal/noise ratio and if you move the amplifier to the antenna you increase that even more. The improved reception are very obvious when monitoring. There are 16 port $25 CATV splitters that have a 16dB loss at each output, perfect to be used with a 20dB $30 low-noise amplifier that are powered from USB 5volt. Instead of ordering or making coaxes with BNC at both ends, make one end with F connectors, that costs the same, and you have replaced a $800 Stridsberg 16 port combiner with a $55 dollar one that have higher and better specs.

/Ubbe

 

[cg]

Digital Loggers also makes one.

Wideband RF Multicoupler - 16 Radios, Surge Protected, 50 Ohm

16 Port Active RF Multicoupler, ships now, free trial

www.digital-loggers.com

I have 2 of them and have experienced failure of something several times that required a return to the factory for repair. The last time they told me they were going to drop them from the line but they are still on the webpage. My Stridsbergs on the same antenna never had issues and the CATV amplified splitter is fine as well.

chris

 

[N9JIG]

I bought an MC204 passive 4-port multicoupler this week and if I have time this weekend I will swap it out with the current MCA204M. While the active unit has worked well here I want to see if a passive device ahead of the active ones would perform better. Stridsberg actually recommends this.

 

[buddrousa]

Keep me posted as I have both and the passive is the spare.

 

[Ubbe]

I want to see if a passive device ahead of the active ones would perform better. Stridsberg actually recommends this.

Their active units overloads easily due to it's bad IP1 and IP3 data. So I can see that attenuating a signal 6dB from a 1-4 splitter installed before their active devices will help its performance, but that will also be like making your antenna receive a 4 times less signal level.

One of Stridsbergs customer complained about the bad overload and they actually modified his multicoupler with less gain to increase the IP1 and IP3 data, but it also ment that the multicoupler attenuated the antenna signal.

/Ubbe