Coax for the shield

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Reeltarded
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Coax for the shield

Post by Reeltarded »

I have seen a bunch of pics where guys use coax of varied types to the first stage.

What would be the best choice? I have miles of RG6 quad laying around, and I think my new amp needs help in the RF zone. eeeeeeeee..

Thanks! Fight amongst yourselves!
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playonit
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Re: Coax for the shield

Post by playonit »

I believe most use rg174...



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Phil_S
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Re: Coax for the shield

Post by Phil_S »

If I'm not mistaken, RG-6 is fairly fat, maybe like a drinking straw, for F connectors for CATV. RG-174 is much skinnier. I think the RG-6 will work, but it will be difficult to work with and that's the problem! You can buy RG-174 for probably $.020/ft, so $1 worth will keep you for several amps. I'd get the skinny stuff.
gingertube
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Re: Coax for the shield

Post by gingertube »

I use off cuts from my day job:
RG400 from GPS Antenna Cables in Aircraft
RG188 from Hi Speed 50 Ohm TTL Cables
RG187 from 75 Ohm Video Cables
etc.

Don't get hung up about the approximately 100pF per meter of coax cable capacitance - it is distributed along the wire along with the inductance and so the cable acts as a transmission line where the distributed capacitance and distributed inductance act to cancel each other - well that's a simplistic view but will suffice for audio work.

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Re: Coax for the shield

Post by Prairie Dawg »

I have done things like take a pencil and wrap thirty or so turns of hookup wire around it and ground one end. It works well if you have the room for it.

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gingertube
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Re: Coax for the shield

Post by gingertube »

Yep that does work - You've probably seen it done in some Fenders, but no better than simply twisting 2 wires together (min 3 and max 5 twists per inch) and then choosing either wire as the shield and connecting it only one end.

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Ian
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Reeltarded
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Re: Coax for the shield

Post by Reeltarded »

I have loads of RG6 quad shield. Imma try a piece or two.

I like the thought of it holding the route I train into it too. Yay.
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Masco
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Re: Coax for the shield

Post by Masco »

Quadra-shield is some thick rigid stuff. Center conductor/dielectric/foil/braid/foil/braid, insulator. Can you even solder the braid? RG-59 is even hard to work with.
I've been using RG-174, but haven't seen much offerings of anything other. I'm curious to hear what others are using (and their source). Seems like most amps I've serviced have something other than RG-174.
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Reeltarded
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Re: Coax for the shield

Post by Reeltarded »

It can be soldered. I have done it before on A installs.
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sonicmojo
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Re: Coax for the shield

Post by sonicmojo »

Masco wrote:Quadra-shield is some thick rigid stuff. Center conductor/dielectric/foil/braid/foil/braid, insulator. Can you even solder the braid? RG-59 is even hard to work with.
I've been using RG-174, but haven't seen much offerings of anything other. I'm curious to hear what others are using (and their source). Seems like most amps I've serviced have something other than RG-174.
I am pretty fond of the white RG-188 I got from Apex Jr. Very easy to work with compared to RG-174, IMO, and teflon so you won't burn it.
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crbowman
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Re: Coax for the shield

Post by crbowman »

sonicmojo wrote:
Masco wrote:Quadra-shield is some thick rigid stuff. Center conductor/dielectric/foil/braid/foil/braid, insulator. Can you even solder the braid? RG-59 is even hard to work with.
I've been using RG-174, but haven't seen much offerings of anything other. I'm curious to hear what others are using (and their source). Seems like most amps I've serviced have something other than RG-174.
I am pretty fond of the white RG-188 I got from Apex Jr. Very easy to work with compared to RG-174, IMO, and teflon so you won't burn it.
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Structo
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Re: Coax for the shield

Post by Structo »

+2
Tom

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Reeltarded
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Re: Coax for the shield

Post by Reeltarded »

I have to get some tubes from Steve today. I will get couple feet of that too maybe.
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Structo
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Re: Coax for the shield

Post by Structo »

Do you live in the area where Steve's warehouse is?

I love going to places like that.
It's a pity but those places are few and far between anymore.

Used to be surplus place in my town, I could go there and two hours would go by without any thought to time.

There still is one place but they don't seem to get anything new and have sold most of the good stuff.
Tom

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ApexJr.
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Re: Coax for the shield

Post by ApexJr. »

For those who can't make it to my warehouse
Here's a 2:47 tour...

http://www.youtube.com/watch?v=J6DNTYm7kWA


Steve
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