coax question?

[zz0468]

I tend to agree except that it seems that the general concensus on RR is that each connector, adapter or patch cable potentially diminishes your signal by some amount.

The "general consensus" here is frequently wrong. You end up with volunteer firefighters and security guards arguing about technical things with radio engineers with 20 or 30 years of experience. And there sometimes seems to be more security guards here than engineers. But I digress...

Yes, those adapters and patch cables have losses. What becomes a point of contention is whether those losses are significant or not. The previous comment about requiring around 3 db to notice is correct. When you figure that each connector probably adds less than a quarter db, that translates to a LOT of connectors in the line before YOU notice a difference.

The other thing to keep in mind is that once an FM receiver is in saturation, it really doesn't matter WHAT the signal level is, it's just full quieting. If you're operating so close the the threshold that a db or two makes a difference, you need to rethink what you're doing and how to go about it.

 

[DPD1]

I think there's oftentimes an assumption that everything in a system relates to gain or gain loss, when there's more to it than that. If anything is going to go bad in a system, it's very often going to be a connector. Connectors and adapters are the weakest link. There's many things that can go bad on them... General corrosion, expansion and contraction pulling them off, water freezing inside and expanding, water seeping through and into the coax... Anytime you have an electrical connection made by just surface contact, it's never a good thing. So the more of that you have, the more you're increasing your chances of problems. It's not the end of the world to have a few things in line, but it's just good practice to try not to. If something fails, then you don't have any signal at all. Which makes the whole db thing kind of pointless.

Dave
http://www.dpdproductions.com
- Custom Scanner, Aviation, MURS, GMRS, Marine & Ham Antennas -

 

[fuzzymoto]

This all seems to lean me away from the associated adapters/connections necessary to have a grounding block in-line on my coax....although I've always assumed a grounding block was a good idea to use.

 

[dbox1]

This all seems to lean me away from the associated adapters/connections necessary to have a grounding block in-line on my coax....although I've always assumed a grounding block was a good idea to use.

Any advice that would steer you away from NEC recommended installation guidelines and local code requirements is simply bad advice.

Any quality cable properly terminated, and if used outdoors being properly protected, will not lead to any significant loss of signal. I'm not saying that cables outside do not require periodic inspection and maintenance, but to remove the most basic of protection for you and your equipment is not a good decision.

 

[Taloniilm]

If I was going with the 996, I'd use the D-130J with LMR400. My thoughts being..."why run a Ferrari on Firestones when you can have Pirrellis for just a few bucks more" .

BTW, I have two 20-176's feeding a RS 2050 and a RS 2006 thru RG8... gets the job done pretty good for low bucks.

 

[N_Jay]

If I was going with the 996, I'd use the D-130J with LMR400. My thoughts being..."why run a Ferrari on Firestones when you can have Pirrellis for just a few bucks more" ..

Because bad analogies lead to bad decisions.

BTW, I have two 20-176's feeding a RS 2050 and a RS 2006 thru RG8... gets the job done pretty good for low bucks.

A better example of why it is dumb to drink $5 a bottle water in the Benz, but tap water in the Ford.
"Good Enough", is "GOOD ENOUGH", and "better" is not always any "BETTER".