Alternative to Stridsberg

[N9JIG]

I have had a couple people ask me about alternatives to Stridsberg multicouplers for scanners. I suggested things like TV units (Electroline etc,) but they don’t want to deal with F-Connectors. Making their own (like I did) is also beyond their purview.

Stridsberg has been non-responsive recently. I don’t know if they are still operating.

Anyone else make commercially available multicouplers these days with BNC connectors?

 

[KC1UA]

There was this, and it's been a while since I tried, but one inquiry to them went without a response. Unknown on their current status, if any.

Cross Country Wireless HF/VHF/UHF Multicoupler

www.crosscountrywireless.net

 

[dimab]

Has anyone tried channel master? Like this - TV Antenna Booster 8

 

[prcguy]

If you real lucky you might find a military or spook surplus multicoupler from MU-DEL or Aiken Labs or Norlin or ??

 

[rf_patriot200]

I have had a couple people ask me about alternatives to Stridsberg multicouplers for scanners. I suggested things like TV units (Electroline etc,) but they don’t want to deal with F-Connectors. Making their own (like I did) is also beyond their purview.

Stridsberg has been non-responsive recently. I don’t know if they are still operating.

Anyone else make commercially available multicouplers these days with BNC connectors?

I just bought a second 204MIL a month ago, no problems ordering it. Wow, I hope their company is is still up !

 

[Ubbe]

Always use pigtails when connecting between different devices that use F or SMA to avoid any adapter issues.



/Ubbe

 

[rf_patriot200]

Always use pigtails when connecting between different devices that use F or SMA to avoid any adapter issues.



/Ubbe

Obviously ! No Adapters needed here.

 

[K7EK]

I have had a couple people ask me about alternatives to Stridsberg multicouplers for scanners. I suggested things like TV units (Electroline etc,) but they don’t want to deal with F-Connectors. Making their own (like I did) is also beyond their purview.

Stridsberg has been non-responsive recently. I don’t know if they are still operating.

Anyone else make commercially available multicouplers these days with BNC connectors?

Stay away from Cross Country Wireless multicouplers! They are junk and customer service stinks!


Mine lasted mere days upon receipt.

Customer service is non existent.

They told me to return my unit for repair or possibly replacement, as it was still under warranty. I did so at great personal expense, despite being on a fixed income. Insured overseas shipping is not inexpensive.

Unfortunately when the defective unit arrived at the designated address, it was rejected and returned to me with no explanation and no new/working replacement multicoupler. What??!! That is just not right.

Subsequent communication with Cross Country Wireless became an exercise in futility. They initially responded with a vague innuendo, filled with excuses without solutions, and then they finally stopped communicating altogether.

So, this very dissatisfied customer is out several hundred dollars for the initial defective multicoupler purchase, plus expensive return shipping which should have been covered by them, as the unit was still under warranty.

Now, a couple of years later, I still don't have the badly needed HF multicoupler for my CW Skimmer and shortwave radio monitoring hobby. I guess I will end up trying for an 8- port unit from Stridesberg, if they are still in business.

Thanks for reading.

Best regards,

Gary, K7EK

Radcliff, KY (EM77at)

 

[dimab]

Has anyone tried channel master? Like this - TV Antenna Booster 8

just tried this - totally useless for my scanning setup. all 800 signals went dead. did several tests switching between stridsberg and channel master.

 

[Ubbe]

just tried this - totally useless for my scanning setup. all 800 signals went dead. did several tests switching between stridsberg and channel master.

The specification says it goes up to 608MHz. Being so specific of that frequency probably means it will be dead at 700MHz and higher.

" 470-608MHz. (Filters / Signal Attenuation is Applied to Frequencies Outside of these Bands)"

/Ubbe

 

[prcguy]

The specification says it goes up to 608MHz. Being so specific of that frequency probably means it will be dead at 700MHz and higher.

" 470-608MHz. (Filters / Signal Attenuation is Applied to Frequencies Outside of these Bands)"

/Ubbe

A lot of newer CATV distribution amps may have filters to reduce 5G interference. The old UHF TV band used to go to 806MHz but that's been moved down to the 600MHz range. With that, even older UHF distribution amps would only be rated to 806MHz and you would want to go to at least 896MHz for 800 public service and possibly to 940MHz or higher for commercial 900LMR, broadcast links, etc.

These are just a few of the reasons I never use TV amps for receiver distribution.

 

[Marcy57]

Wow, all this has me wondering now? if I can get another PRE-20 Pre-Amplifier from them?
wanted to get another think it works vy well! ...73,s Marcy

 

[buddrousa]

I have had 2 Cross Country both of mine are HF/VHF/UHF 0.5 to 1350 MHz and I have never had a problem with either one.
The HF/VHF/UHF covers 0.5 to 1350 MHz, the VHF/UHF Multicoupler covers 45 to 1350 MHz and the HF Multicoupler covers 50 kHz to 35 MHz.

 

[prcguy]

Wow, all this has me wondering now? if I can get another PRE-20 Pre-Amplifier from them?
wanted to get another think it works vy well! ...73,s Marcy

The specs on a PRE-20 are 18dB gain, no problem there, 40MHz to 1GHz, ok, 1dB compression at 12dBm, really bad and a noise figure of 3.5dB which is crap for a low level preamp. With multiple signals on the input as you would have connected to an antenna, an amplifier will produce IMD at a much lower level than the 1dB compression point.

So with a broad band Discone antenna feeding it in a busy city it will most likely produce a raised noise floor and ghost signals all over the place. I've measured aggerate signal levels off a Discone around my area and right off the antenna I was seeing levels reaching -30dBm and more which will easily trash out the PRE-20 preamp.

I would look for specs more like 12-15dB gain, 1dB compression 27dBm (1/2 watt) and the lowest noise figure you can find at that power level. You might have to live with 2dB or higher noise figure but your noise floor will not be impacted that much and you will have less chance of ghost signals (IMD) generated within the preamp trashing out your reception.

The only way around this is to limit a broad range of frequencies from getting to the preamp by using filters at the front end of the preamp. No filter lets in everything from DC to light causing high level signals you don't care about trashing out your preamp and causing problems. A simple FM trap filter is a must for a broad band antenna/preamp but individual VHF lo, VHF high, UHF and 700/800 band pass filters can allow the preamp to amplify only what you want and limit things you don't want and wreaking your reception.

With that out of the way one amplifier series I use for broad band stuff is the MiniCircuits ZHL-1010 with 10dB gain across 50-1000MHz, 1dB compression of 26dBm (14dB higher than the PRE-20) and unfortunately a noise figure similar to the PRE-20 at 3.5dB. There is also a 20dB gain version which is better when running an 8-way or larger splitter after the amplifier. These two amps show up on eBay for good prices and I've bought them in the $50 range where new from the factory they are $276 for the 10dB version and $289 for the 20dB version.

Somewhere out there is a better amp with lower noise figure and I'll find it someday.

 

[Marcy57]

I have none of that...noise or ghost sigs as you mention every body,s QTH is different mine works very well here and very pleased with it ...but tks for the input 73,s Marcy

 

[bearcatrp]

Prcguy, these amplifiers you’re talking about have me interested. If I get one, do I put this between the radio and my 4 port or between my 4 port and my coax coming from my antenna? I also have a fm trap filter between the 4 port and coax to my antenna. Always thought amplifiers bring in higher noise floor.

 

[buddrousa]

If you live in a high RF area the amp will hurt more than it helps if you are in a low RF area it could help.
The closer you get to the antenna the more it should help.

 

[prcguy]

Prcguy, these amplifiers you’re talking about have me interested. If I get one, do I put this between the radio and my 4 port or between my 4 port and my coax coming from my antenna? I also have a fm trap filter between the 4 port and coax to my antenna. Always thought amplifiers bring in higher noise floor.

The best place for an amplifier is at the antenna to set the system noise figure and carrier to noise ratio there and provide a higher signal level to overcome coax loss. Second best might be near the radio and before any splitting. Any loss before the preamp will raise the system noise figure.

An FM trap filter would go before the preamp to limit strong broadcast signals from reaching the preamp and eating up its dynamic range. That will place a small amount of loss, should be less than 1dB before the preamp but the benefits of removing high level broadcast signals before the preamp outweigh the slight loss and higher system noise figure.

 

[Ubbe]

The specs on a PRE-20 are 18dB gain, no problem there, 40MHz to 1GHz, ok, 1dB compression at 12dBm, really bad and a noise figure of 3.5dB which is crap for a low level preamp.

There's no reason to believe anything else than that the pre-20 are of the exact same design as are used in their multicoupler to amplify the signal before it is split into several outputs, so their multicoupler would have the same specification.

If using a discone antenna it will receive a lot of bandwidth. A standard vertical antenna usually have a limited bandwidth of maybe 5-10% of the frequency and will work as a natural bandpass filter. Most people might think they will spend less buying and antenna that covers all frequencies but you might have to spend more on it buying filters and other solutions to be able to use it properly. Then it would be wiser to use several more narrow banded antennas and connect to a diplexer or triplexer at the antennas to make use of a single coax cable to get less issues with out of band signals, especially if a diplexer or triplexer are also used at the other end of the coax to split up the signal to separate scanners.

/Ubbe

 

[nickwilson159]

Somewhere out there is a better amp with lower noise figure and I'll find it someday.

I've been trying a pair of these and have been happy with them so far:

E-PHEMT PreAmplifier

Note that it did take around a month for them to arrive since they're made to order, but I have yet to find anything else close to these specs for a reasonable price.