I tried 10 digicon connectors and all 10 froze i was 0 for 10 then i decided to use the junk hex crimp onesmiguelaqui said:
Which is better solid copper or copper-clad center conductor?
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Skin effect
At high frequencies there is one thing to consider on wire resistance besides the DC resistence: skin effect.
The current intensity falls off exponentially with depth. The depth of penetration (s=sigma) is the depth at which the current intensity has fallen to 1/e of its value at the surface, where e equals 2.718.
Where the diameter of the conductor is large compared to the depth of penetration, the total current is the same as if the surface current intensity were maintained to a depth of penetration.
For example, for copper the depth of penetration is as follows:
MHz Depth of Penetration sigma (mm)
.1 .209
1 .066
10 .021
100 .0066
1000 .0021
For other materials the skin dpeth can be calculated using the formula:
s = 503.3sqrt(rho/(urf)) millimeters
rho = resistivity in ohm-meters
= 1.72x10e-8 for copper or 2.83x10e-8 for aluminum
ur = mu r = relative magnetic permeability
= 1 for both copper and aluminum
f = frequency in magahertz
http://www.epanorama.net/documents/wiring/wire_resistance.html
At high frequencies there is one thing to consider on wire resistance besides the DC resistence: skin effect.
The current intensity falls off exponentially with depth. The depth of penetration (s=sigma) is the depth at which the current intensity has fallen to 1/e of its value at the surface, where e equals 2.718.
Where the diameter of the conductor is large compared to the depth of penetration, the total current is the same as if the surface current intensity were maintained to a depth of penetration.
For example, for copper the depth of penetration is as follows:
MHz Depth of Penetration sigma (mm)
.1 .209
1 .066
10 .021
100 .0066
1000 .0021
For other materials the skin dpeth can be calculated using the formula:
s = 503.3sqrt(rho/(urf)) millimeters
rho = resistivity in ohm-meters
= 1.72x10e-8 for copper or 2.83x10e-8 for aluminum
ur = mu r = relative magnetic permeability
= 1 for both copper and aluminum
f = frequency in magahertz
http://www.epanorama.net/documents/wiring/wire_resistance.html
stone phillips420 said:
I just remebered....I lied to you. Back in 2001, when I first saw Digicon, a contractor was telling me that they were the best made, etc, so he showed me a few.
The first one I put on locked up...I took pliers, grabbed the bottom of the connector, then twisted the nut with a wrench and it started to move.
Yes, I agree, I big pain for such an expensive connector.
As far as skin effect....I had never heard of that!!
Mike_H, I'm pretty sure no one on the board will use the formulas, that's why I limited my post by simple mentioning the term. 
I recently thought of something...I just have known better!!! If solid copper would carry signal better, the cable companies would use it for their trunklines. I'm sure that the truckline I messed with in the 90's was copper-clad.
I remember being told that the signal was carried on the outside of the cable by on of the lead techs!
This same guy told me that SNS connectors, which they had been using since 1989, were going to be the style everybody would be using. I disagreed, I told him that the Raychem EZF would dominate because they could be installed in 1/2 the time a SNS coud be installed...it's a good thing I didn't invest in Raychem!! Although, if Raychem would have just added an o-ring, I think they might have won!
That same guy told me that he would not worry about the satellite companies causing any serious competetion until they had two-way communcation, which, at the time, we did not even have. ....I'm on the fence about what he would consider "serious competition"
My next question is....is it possible that cable that is made for satellite signal, possibly worse for cable? I'll open a new thread for that.
I remember being told that the signal was carried on the outside of the cable by on of the lead techs!
This same guy told me that SNS connectors, which they had been using since 1989, were going to be the style everybody would be using. I disagreed, I told him that the Raychem EZF would dominate because they could be installed in 1/2 the time a SNS coud be installed...it's a good thing I didn't invest in Raychem!! Although, if Raychem would have just added an o-ring, I think they might have won!
That same guy told me that he would not worry about the satellite companies causing any serious competetion until they had two-way communcation, which, at the time, we did not even have. ....I'm on the fence about what he would consider "serious competition"
My next question is....is it possible that cable that is made for satellite signal, possibly worse for cable? I'll open a new thread for that.
I would say that cable made for satellite, is good for cable. Most cable systems are being forced to use digital boxes or cards. Hence, the need for swept-testing requirements to be higher (at LEAST 1 Gig Hz)
The Solid copper core (SCC)coaxial is better conductor than the Copper Clad Steel (CCS) core. But the CCS is softer and you have to be careful around bends. If I have the choice I would go with the SCC. With copper prices going through thr roof, you will see a high increase on SCC coaxial.
BTW, I like the PPC EX6XL compression fittings. I have never had one freeze after compression.
BTW, I like the PPC EX6XL compression fittings. I have never had one freeze after compression.
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We just came to conlusion about conductivity, when you begin the song again - "The Solid copper core (SCC)coaxial is better conductor than the Copper Clad Steel (CCS) core".
There are TWO type of signals - RF 0.95-1.45/2.15 GHz uV and 13/18/20 VDC 0.7A
Your statement pretty wide and don't accurate. Personal opinion based on ?
There are TWO type of signals - RF 0.95-1.45/2.15 GHz uV and 13/18/20 VDC 0.7A
Your statement pretty wide and don't accurate. Personal opinion based on ?
I have had several of those split on me! A few of the PPC EXs would break when connecting with a wrench.Sadoun said:
as a matter of fact...one of the guys from the old cable days is now in charge of the Adelphia system around here....He got them to start using the Snap-n-Seals again because , he said "out of 15 years, we NEVER HAD A BAD ONE, we went to PPC and had several problems " He said too many of the PPCs would split on quad. Also, you don't have to worry about the SNS freezing up!!
