Multi-couplers and related pigtail coax lenght?

[iMONITOR]

Does the length of coax pigtails use with multi-couplers influence performance? I noticed Stridsberg sells coax pigtails to be used with their multi-couplers. I know they're easy and cheaper to make.

"Coaxial patch cables in two lengths 4 feet and 6 feet. These cables are made from premium Belden RG-58A/U and Amphenol BNC connectors. All cables are tested on a Network Analyzer for reliable performance up to 1 GHz"



I was surprised that they're using RG-58A/U for up to 1GHZ. I was also surprised the shortest they sell is 4-feet. Is the length important within reason? Would it have any ill effect if you used 1 or 2 feet?

 

[mule1075]

I use 3 6' and 1 25' and don't see any difference. And I bought cheap ones off of EBay. Stridsberg is like any other company trying to make a buck. Don't get me wrong i like my stridsberg 4 port but I have a scientific american I believe is the brand cable drop amp that works just as good for a fraction of the price.

 

[mmckenna]

Length isn't critical, it's not a tuned length.

Benefit to RG-58 is that it's really flexible and won't put strain on antenna connectors of your radios. For short lengths, even 4 and 6 feet, the loss is negligible.

 

[buddrousa]

I only remember in the old CB days jumper length was like 3 feet intervals but all the jumpers I use with my scanners are cut to length in my setups and I see no difference in all my connected scanners logging with PROSCAN.

 

[mmckenna]

I only remember in the old CB days jumper length was like 3 feet intervals….

Yeah, just convenient lengths, nothing else behind it.

If you are going to make your own, make them the length you need. Only time you need to worry about length is if you are tying duplexer cans together, or making tuned length shorting stubs.

 

[Ubbe]

Coax lenght can be tuned to a frequencys 1/2 wavelenght but your scanner are not set to just receive one single frequency, you probably have a huge frequency span you are scanning, so it would anyhow be impossible to match the coax lenght.

/Ubbe

 

[iMONITOR]

I think I was getting confused with coax stubs, not jumpers.

Thanks everyone!

 

[N9JIG]

While longer coax would give higher loss, at these lengths the difference between a 3-foot cable and 10-foot cable is so slight that it is probably not measurable much less noticeable. It is mostly a matter of neatness. Adapters (like BNC-SMA etc.) would cause more loss than another feww feet of coax.

I keep a "Hamfest List" on my phone for specific cables with the ends and lengths needed for my shopping needs. When I could not find the ones I wanted I had some made at a local radio shop. I could have made them myself but I have never had much success putting on connectors.

 

[majoco]

I could have made them myself but I have never had much success putting on connectors.

Practice, practice and practice!

 

[N8YX]

Old thread, but I have probably 30 different jumpers running from my power dividers to the various receivers in two areas of my residence. Some are RG-8X, some RG-174, others RG-336 or 400. Lengths range from a foot to several feet; connectors run the gamut from SMA to F to BNC to N. None of the receivers seem to notice what's driving them. There are active inline amplifiers at each major distribution point, however.