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RF coax testing & verify

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Craig Hauber:
What would be needed to test and verify antenna coax cables?  I'm using Belden 9913 and LMR-400 and would like to know that there are no issues once lines are installed and terminated. 
Also when I get rental packaged systems for tour I've had some fairly sketchy looking older cables and would love to verify them before trusting.
Most installed lines are either 50, 75 or 100ft and using crimped BNC ends with tools and connectors from the same vendor as the bulk cable.  But would love to be able to verify rack patch BNC's too as well (and if it's capable, use the gear for testing HD-SDI cables.) 
Even factory pre-made cables may have issues after shipping and the unintentional abuses of installation or tour use.

I'm having a suspicion that such dedicated equipment is very expensive, but if there's a way to do it with a multiple pieces of more affordable (or used) gear or equipment that HAMs mights have?  Can overall larger size, longer setup time and overall convenience can be used to compensate for the cost of a new nifty handheld unit that costs $12k?

Mac Kerr:

--- Quote from: Craig Hauber on August 05, 2022, 12:38:33 PM ---
I'm having a suspicion that such dedicated equipment is very expensive, but if there's a way to do it with a multiple pieces of more affordable (or used) gear or equipment that HAMs mights have?  Can overall larger size, longer setup time and overall convenience can be used to compensate for the cost of a new nifty handheld unit that costs $12k?

--- End quote ---

Yes. You can get a Chinese SA with a reflection bridge for around $2000. The Siglent SSA3021 is around $1400 and the bridge and additional software to do VSWR measurement is $670. It is a 2.1MHz SA with tracking generator. The downside is it is not battery operated, it requires a 120V supply.

Mac

Rui Lisboa:


Why go scalar when you can introduce time in the equation for further analysis if needed?
Go with a chinese VNA. Cheap and portable.
Also in the Siglent realm: SVA is just a tad more expensive than the SSA. You get 100 hours of several of the costly licenses, you can do TDR and actually measure length and distance to fault if you need it.
Either way go VNA. Little more of a steep learning curve but there is a lot of learning resources on the web.

Craig Hauber:

--- Quote from: Mac Kerr on August 05, 2022, 01:48:13 PM ---Yes. You can get a Chinese SA with a reflection bridge for around $2000. The Siglent SSA3021 is around $1400 and the bridge and additional software to do VSWR measurement is $670. It is a 2.1MHz SA with tracking generator. The downside is it is not battery operated, it requires a 120V supply.

Mac

--- End quote ---
There's a lot of acronyms here to deduce and learn about but thanks for the replies.
-Do I actually need a Spectrum Analyzer?  Could I just send a signal generator tone down the line and measure with some kind of receiver, re-tune and repeat until I cover all the applicable frequencies of the wireless we are installing?
Compare to a known-good line (i.e. one that's been in service for years with no issues)
My TinySA unit generates RF -never done it before and considered such a function fairly "dangerous"

Just trying to avoid $2100 at this moment as unexpected expenses are piling-up this season -budget for this was around $800, but that was totally an uneducated guess.  And uneducated I really seem after following the rabbit-hole of links your acronyms led to.  $2100 seems relatively cheap compared to some of the solutions I've since discovered.
Maybe ignorance is bliss and I should just buy pre-made verified lines and leave the excess coiled above ceiling instead of re-terminating?  Still worried about any "nicks or dings" that may happen during installation.

Russell Ault:

--- Quote from: Craig Hauber on August 09, 2022, 02:04:14 PM ---{...} budget for this was around $800 {...}

--- End quote ---

Something like a PocketVNA would fit that budget, although it's worth reading up on its limitations (there's no such thing as a free lunch, particularly at an almost-two-orders-of-magnitude price reduction).

-Russ

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