Coax Question

[djeplett]

In the good ol' Fleet Farm ad this week they're listing "Gemini Quadshield Coaxial 2.2 GH" cable on sale 50' without ends for $15.99.

My question is this: is anyone familiar with this cable and would it be a good choice for scanner use? I know the impedance will probably be 75 ohm so it will not be a match, but there is no concensus on RR as to wether that's bad or not.

I've found it listed elsewhere online as being RG6 but I would assume that means its compatible with RG6 connectors. The other listings said it is for satellite applications and that it is "rated for 2.2GHz". Who knows how well it does at 2.2, but I'm wondering if it would be around 6db loss or so at 800MHz... That would be acceptable to me for this kind of price.

 

[N_Jay]

In the good ol' Fleet Farm ad this week they're listing "Gemini Quadshield Coaxial 2.2 GH" cable on sale 50' without ends for $15.99.

My question is this: is anyone familiar with this cable and would it be a good choice for scanner use? I know the impedance will probably be 75 ohm so it will not be a match, but there is no concensus on RR as to wether that's bad or not.

I've found it listed elsewhere online as being RG6 but I would assume that means its compatible with RG6 connectors. The other listings said it is for satellite applications and that it is "rated for 2.2GHz". Who knows how well it does at 2.2, but I'm wondering if it would be around 6db loss or so at 800MHz... That would be acceptable to me for this kind of price.

Do a Google search. RG-6 loss is well documented.

2.2 GHz sounds a bit high, but satellite systems are preamplified so loss is less of a concern.

Don't worry about the minor impedance mismatch, is it not significant in wide-band/untuned systems like scanner antennas.

 

[djeplett]

Yeah, from what I've found while searching RG6 is about 6db at 800MHz so I'd be happy with that for this price.

Now on to connectors... the antenna I'm putting up is not good at 800MHz and I plan on changing it within 2 to 5 years when the Wisconsin State Patrol go to a TRS. So if I get a good antenna I'll be changing the connector on the antenna end at that time but for now I need to end with a PL-259. For obvious reasons the PL-259 is not listed anywhere for use with RG6, so do I use the reducers for RG8? It looks like RG8 is the same OD as RG6 so will this work? Also, is the same true for the scanner end... do I use BNC connectors for RG8?

Thanks for answering N_Jay... I was hoping you would since you seem to know what you're doing. :wink:

 

[LarrySC]

NO. You dont put RG-6 on a PL. You buy a PL to "F" adp. Put regular "F" on both ends of coax. Put "F" twist on for the radio end or an "F" to BNC. Pan Pacific makes a PL to F with a GOLD TIP part # RFA-813. I can send you a picture if you email me direct. Good Luck

 

[djeplett]

The part number for the F to PL259 adapter was actually RFA-8173 and it does have the gold center conductor. It can be found at many sellers online if you search for that part number in quotes on Google or Yahoo. I have my order placed and it's on its way. I will update this thread when I get it all installed to let everyone know how it turned out.

Thanks LarrySC and N_Jay!

 

[Al42]

Excuse me, but you certainly can put a PL259 on RG6 with a reducer. It's best to stay away from PL connectors altogether above 30 MHz, but if the antenna or the scanner has an SO239 jack you have no choice (unless you want to change that to an SMA). And it's always best to stay away from adapters. Even the best ones cause at least a little impedence bump.

As far as the original question: 50' of 6db loss@800 MHz for $16? Unused and not stolen? I seriously doubt it. Sure the cable may be rated at 2.2 GHz - all that means is that someone ran a 2.2 gig signal through it and measured the loss. That's what "rating" a cable means - measuring the loss. If it's 100db/hundred feet, it's still "rated". Certified for use is different.

 

[pro92b]

Excuse me, but you certainly can put a PL259 on RG6 with a reducer. It's best to stay away from PL connectors altogether above 30 MHz

I've only found reducers for RG-58 and RG-59. RG-6 is larger than either of those. Who makes a reducer for RG-6?

Cambridge rates their PL-259 for 500 MHz but I probably would not use one above the VHF-HI band if I could avoid it.

As far as the original question: 50' of 6db loss@800 MHz for $16?

Mouser has Belden 9116, 100 foot spool, 6 dB loss at 870 MHz for $24.65.

 

[crayon]

For those that would like some more detailed information on the subject:

http://www.qsl.net/vk3jeg/pl259tst.html

 

[djeplett]

As far as the original question: 50' of 6db loss@800 MHz for $16? Unused and not stolen? I seriously doubt it.

Actually, I got it for $10 for 50'.

if the antenna or the scanner has an SO239 jack you have no choice

That's exactly what I stated in my response to N_Jay:

the antenna I'm putting up is not good at 800MHz and I plan on changing it within 2 to 5 years when the Wisconsin State Patrol go to a TRS. So if I get a good antenna I'll be changing the connector on the antenna end at that time but for now I need to end with a PL-259.

If you can point me to a part number and manufacturer of a PL259 that can work on a RG6 I'd appreciate it. However, it looks to me like that is not possible as everything I've read says a PL259 is 50 ohm, not 75 ohm.

 

[Tweekerbob]

Excuse me, but you certainly can put a PL259 on RG6 with a reducer.

Please enlighten me as to what reducer one should use when dealing with RG-6QS (quad shield). This happens to be thick enough that it will not work with a rg-8x reducer, nor w/o a reducer. Regular RG-6 yes, this stuff no way Jose. This is infact the original poster's coax in ?

Ryan
[/quote]

 

[djeplett]

Regular RG-6 yes

Can you give me a part number and manufacturer that is for regular RG6, or are you saying from experience that regular RG6 works with the adapter for RG8 or something?

BTW, I decided on a compression F connector at the F to PL259 adapter at the antenna and then a compression BNC at the radio:

http://www.smarthome.com/849322.html
Steren 201-167BK - Compression BNC for RG6QS

http://store.yahoo.com/technicalconnectionsinc/snthomandbet1.html
Thomas & Betts SNS6QS - RG6 Compression F Connector for RG6QS

 

[Tweekerbob]

Do you have a compression tool?

If not, they are kinda $$$. May want to go with the twist-ons.

Ryan

 

[djeplett]

I was going to go with this one:
http://store.yahoo.com/technicalconnectionsinc/dacafcocoto.html

I know it's an El Cheapo, but it only has to crimp a few and then it will end up sitting in a drawer for a long time.

How about a part number for PL259s on RG6 cable? Anybody?

 

[K5MAR]

I'm not at home so I don't have my links, but there is a thread on here somewhere that I posted a link to crimp-on PL-259s for RG-6. All Electronics or somebody like that. I'll be home after next Monday if you don't find it, PM me.

Mark S.

 

[djeplett]

Thanks! From another thread:

There are special crimp-style PL connectors made for use with RG-6 coax. I found them a couple of years ago. They were being sold by Alltronics Electronic Supply www.alltronics.com . It is the UHF Male - Cable crimp for RG6U", p/n CU051. They also sell a BNC connector - p/n CB081. I haven't bought any in several years, so I can't guarantee they are still available, but it's worth checking into.

Mark S.

Unfortunately, Alltronics has a $15 minimum order. I'll order it sometime in the future just for fun and try it on my quad shield to see if it works. For now I don't need $15 in connectors or other stuff.

 

[K5MAR]

Not a problem for me! I can find that much to order in about 5 minutes. :lol: They usually have neat stuff like cig. lighter adapters (Handy for temp. mobile setups) headphones, etc. I've done several mobile setups in the last couple of months, I'll have to restock pretty soon.

Mark S.

 

[kb2vxa]

Hi guys,

"For obvious reasons the PL-259 is not listed anywhere for use with RG6, so do I use the reducers for RG8?"

RG-8 does not require reducers.

"It looks like RG8 is the same OD as RG6 so will this work?"

No, RG-8 is 1/2" OD, RG-6 is somewhere between that and the diameter of RG-59 which uses a slightly larger ID reducer than RG-58. Use a drill press and vise to bore the hole larger for RG-6, then ream out the larger end slightly, chamfer it more or less as it was.

Careful, you end up with a thin wall and you just may have to strip the jacket back for proper fit, then waterproof the whole connector once installed on the antenna as per ISO 9000 specs. (They replace Mil Spec so you can go with those.)

 

[bsavery]

ISO 9000 has absolutely NOTHING to do with how you terminate or waterproof a connector!

ISO 9000 is a set of requirements for a Quality Management System overseeing the production of a product or service. It is not a standard for ensuring a product or service is of quality; rather, it attests to the process of production, and how it will be managed and reviewed.

Read this. or any of the other zillion hits on ISO 9000 you can get from Google.

ISO 9000 also absolutely did not replace MIL-SPEC. MIL-Spec requirements for items are far more stringent than ISO.

Bob
(Who once worked for a ISO 9000 certified company that was also certified to build MIL-SPEC.)