A friend of mine gave me some "surplus" RG-400 from the place he
worked a few years ago. I got sold on the stuff, and with 50-75 feet
of 5 foot pieces, I've been fortunate enough to use it with reckless
abandon for some time :)
On Dec 22, 2007, at 1:27 PM, Paul N1BUG wrote:
> Oops. I forgot
Oops. I forgot to mention double shielded cable for ALL
interconnects is an absolute MUST, at least with my duplexer - it
has notches in excess of 120 dB deep after refurbishing. It doesn't
take much leakage cause problems when you're dealing with notches
like that.
Paul N1BUG
Paul N1BUG wro
Jim Brown wrote:
> I have found that the main problem in using a talkie
> as the receiver for tuning the notch in a duplexer is
> the possible leakage of RF between the signal source
> directly into the talkie. Most talkies are not
> shielded at all, and any leakage will cause you to
> tune a comb
At 12/22/2007 08:19, you wrote:
>Jim
>
>I have used double shielded coax and haven't had too much problem with
>leakage.
>
>73
>Brian
The problem with HTs is that the radio itself is not well shielded. Of
course some are better than others but I haven't found any that are good
enough to use f
This has me thinking in new ways handheld has an ultra-low 50mw
output...
On Dec 22, 2007, at 2:34 AM, skipp025 wrote:
> Hi Cort,
>
> Just something to keep in mind...
> You can use a regular radio as a signal generator just as you
> can use another for your receiver/detector function.
>
>
Jim
I have used double shielded coax and haven't had too much problem with
leakage.
73
Brian
Jim Brown wrote:
I have found that the main problem in using a talkie
as the receiver for tuning the notch in a duplexer is
the possible leakage of RF between the signal source
directly into the tal
I have found that the main problem in using a talkie
as the receiver for tuning the notch in a duplexer is
the possible leakage of RF between the signal source
directly into the talkie. Most talkies are not
shielded at all, and any leakage will cause you to
tune a combination of the signal through
Thanks Skipp025!
I have an old Lampkin service monitor and I've been tuning the
duplexer by using my handheld as a receiver with the Lampkin as the
generator. It just doesn't have enough oomph for proper tuning of the
reject portion of 2 cans in series So I'm working "somewhere" in
the
com
>Subject: Re: RE: RE: RE: RE: RE: RE: Re: Re: RE: [Repeater-Builder] Re:
>Duplexers
>
>Ron , Aw c'mon Ron, dig out those equations from your library so we can all
>see where you're comming from. That way we can get an idea how much reference
>materials you really
of pictures.
I hope you enjoyed this as much as I.
73, ron, n9ee/r
>From: allan crites <[EMAIL PROTECTED]>
>Date: 2007/09/03 Mon PM 04:09:58 CDT
>To: Repeater-Builder@yahoogroups.com
>Subject: Re: RE: RE: RE: RE: RE: RE: Re: Re: RE: [Repeater-Builde
ith HP piece of test
> > > equipment. Was quick and to the point.
> > >
> > > I did not think I had to dig into my libary and dig out the equations.
> > > Same with stating an SWR...thought most would take a reading from a meter
> > > and not having to
did not see you giving your basis for rejecting the statement, but
> > then again I really did not expect it, hi.
> >
> > 73, ron, n9ee/r
> >
> > >From: Gary Schafer < [EMAIL PROTECTED] >
> > >Date: 2007/09/02 Sun PM 08:29:08 CDT
> > >
aving to give the equations.
I did not see you giving your basis for rejecting the statement, but then again
I really did not expect it, hi.
73, ron, n9ee/r
>From: Gary Schafer < [EMAIL PROTECTED]>
>Date: 2007/09/02 Sun PM 08:29:08 CDT
>To: Repeater-Builder@yahoogroups.com
>Subjec
did not see you giving your basis for rejecting the statement, but then
> again I really did not expect it, hi.
>
> 73, ron, n9ee/r
>
> >From: Gary Schafer <[EMAIL PROTECTED] >
> >Date: 2007/09/02 Sun PM 08:29:08 CDT
> >To: Repeater-Builder@yahoogroups.com
>
he statement, but then again
I really did not expect it, hi.
73, ron, n9ee/r
>From: Gary Schafer <[EMAIL PROTECTED]>
>Date: 2007/09/02 Sun PM 08:29:08 CDT
>To: Repeater-Builder@yahoogroups.com
>Subject: RE: RE: RE: RE: RE: RE: Re: Re: RE: [Repeater-Builder] Re: Duplexers
&g
Hahaha a audiophiles... can sell them anything no need for real
physics, just tell them that this device will make things sound better, back
it up with a BS statment that doesn't apply, and charge them 100 bux.
On 9/3/07, Jeff DePolo <[EMAIL PROTECTED]> wrote:
>
>
> > One can see there b
> One can see there becomes a point where the coax will not
> look like coax at low frequencies or atleast have a
> characteristic impedance of something other than it normal value.
Most of this is true (although I don't know what you mean by "coax will not
look like coax"), and I already ackno
RE: RE: Re: Re: RE: [Repeater-Builder] Re: Duplexers
>
>But it is your statement.
>
>73
>Gary K4FMX
>
>> -Original Message-
>> From: Repeater-Builder@yahoogroups.com [mailto:Repeater-
>> [EMAIL PROTECTED] On Behalf Of Ron Wright
>&
yahoogroups.com
>Subject: RE: RE: RE: RE: RE: RE: RE: Re: Re: RE: [Repeater-Builder] Re:
>Duplexers
>
>I was wondering when someone was going to dredge that up from the Beldon
>papers. Good going Jesse.
>But that still doesn't mean or show that coax cable
>From: Gary Schafer <[EMAIL PROTECTED]>
>Date: 2007/09/02 Sun PM 09:07:18 CDT
>To: Repeater-Builder@yahoogroups.com
>Subject: RE: RE: RE: RE: RE: RE: RE: RE: Re: Re: RE: [Repeater-Builder] Re:
>Duplexers
>
>
>Isnât it interesting to note th
The equation is for characteristic impedance which means a line of infinite
length or one that is terminated with a resistive load equalling the
impedance of the transmission line. An interesting note, twisted pair telco
lines are about 600 ohms at baseband levels but are 120 ohms at DSL
frequenci
Correction to below: Change the word "frequency" to wavelength. It should
read;
There is no "high frequency cutoff" but as the spacing of the center
conductor and shield gets larger compared to WAVELENGTH a point is reached
where the propagation mode of the cable changes and other modes come in
ission line including standing waves.
73
Gary K4FMX
_
From: Repeater-Builder@yahoogroups.com
[mailto:[EMAIL PROTECTED] On Behalf Of Jesse Lloyd
Sent: Sunday, September 02, 2007 4:10 PM
To: Repeater-Builder@yahoogroups.com
Subject: Re: RE: RE: RE: RE: RE: RE: RE: Re: Re: RE: [R
PROTECTED] On Behalf Of Jeff Condit
Sent: Saturday, September 01, 2007 10:24 PM
To: Repeater-Builder@yahoogroups.com
Subject: Re: RE: RE: RE: RE: RE: Re: Re: RE: [Repeater-Builder] Re:
Duplexers
Hi all! If a piece of coax is sitting at ground and you suddenly attach a
battery (DC) across it, y
RE: RE: RE: RE: RE: Re: Re: RE: [Repeater-Builder] Re:
> Duplexers
>
> Ok. Coax doesn't have an impedance at DC it has a resistance.
>
> Coax impedance is found by:
> Zo = sqrt [ (R +j 2 pi f L ) / (G + j 2 pi f c) ]
>
> where:
> f is frequency
> L is
m
> Subject: Re: RE: RE: RE: RE: RE: RE: Re: Re: RE: [Repeater-Builder] Re:
> Duplexers
>
> Gary,
>
> Now I know you are kidding, hi.
>
> 73, ron, n9ee/r
>
>
>
> From: Gary Schafer <[EMAIL PROTECTED]>
> >Date: 2007/09/01 Sat PM 08:58:13 CDT
> &g
RE: RE: RE: Re: Re: RE: [Repeater-Builder] Re:
> Duplexers
>
> Gary,
>
> I don't know. Why don't you tell us.
>
> I don't know why gravity will pull me to the ground real fast if I jump
> off a bridge, but I have all the faith in the world it will. Einstin
n, n9ee/r
>
> >From: Jeff DePolo <[EMAIL PROTECTED] >
> >Date: 2007/09/02 Sun PM 12:12:51 CDT
> >To: Repeater-Builder@yahoogroups.com
> >Subject: RE: RE: RE: RE: RE: RE: RE: Re: Re: RE: [Repeater-Builder] Re:
> Duplexers
>
> >
> >> Impedance refers t
freq differences in coax. Maybe not.
Oh well. Good discussion.
73, ron, n9ee/r
>From: Jeff DePolo <[EMAIL PROTECTED]>
>Date: 2007/09/02 Sun PM 12:12:51 CDT
>To: Repeater-Builder@yahoogroups.com
>Subject: RE: RE: RE: RE: RE: RE: RE: Re: Re: RE: [Repeater-B
te: 2007/09/02 Sun PM 12:38:28 CDT
>To: Repeater-Builder@yahoogroups.com
>Subject: Re: RE: RE: RE: RE: RE: RE: Re: Re: RE: [Repeater-Builder] Re:
>Duplexers
>
>Ok. Coax doesn't have an impedance at DC it has a resistance.
>
>Coax impedance is found by:
&g
or
> engineers that allows one to look at some of these issues.
>
> Oh well.
>
> 73, ron, n9ee/r
>
> >From: Jeff DePolo <[EMAIL PROTECTED]>
> >Date: 2007/09/02 Sun AM 09:01:03 CDT
> >To: Repeater-Builder@yahoogroups.com
> >Subject: RE: RE: RE: RE
> Impedance refers to both R and X, resistance and reactance. Impedance
affects all current flow, DC and AC. X affects AC only.
Impedance is specific to AC. There's no such thing as impedance at DC, only
resistance. Look up in the definition of impedance in any engineering text
and you'll find
RE: RE: Re: Re: RE: [Repeater-Builder] Re: Duplexers
>
>>
>> The question is way off base. No one said one cannot carry
>> DC or any other signal on coax. The question was what was
>> the impedance of a coax at given frequencies.
>
>You said coax
>
> The question is way off base. No one said one cannot carry
> DC or any other signal on coax. The question was what was
> the impedance of a coax at given frequencies.
You said coax has a low-frequency cutoff. I'm asking about that
specifically. I didn't ask about about impedance.
> At
hi.
73, ron, n9ee/r
>From: Gary Schafer <[EMAIL PROTECTED]>
>Date: 2007/09/01 Sat PM 08:48:03 CDT
>To: Repeater-Builder@yahoogroups.com
>Subject: RE: RE: RE: RE: RE: Re: Re: RE: [Repeater-Builder] Re: Duplexers
>
>Ron,
>
>Maybe you could tell us why
Gary,
Now I know you are kidding, hi.
73, ron, n9ee/r
From: Gary Schafer <[EMAIL PROTECTED]>
>Date: 2007/09/01 Sat PM 08:58:13 CDT
>To: Repeater-Builder@yahoogroups.com
>Subject: RE: RE: RE: RE: RE: RE: Re: Re: RE: [Repeater-Builder] Re: Duplexers
>
>
ss.
Hope this helps.
- Original Message -
From: Gary Schafer
To: Repeater-Builder@yahoogroups.com
Sent: Saturday, September 01, 2007 6:58 PM
Subject: RE: RE: RE: RE: RE: RE: Re: Re: RE: [Repeater-Builder] Re: Duplexers
How do you know it is not 75 ohms at DC?
How long do you th
ntenna. Wire aint cheap, but a C-130 at the time went for
$25,000,000.
73, ron, n9ee/r
>From: Jeff Kincaid <[EMAIL PROTECTED]>
>Date: 2007/09/01 Sat PM 01:40:02 CDT
>To: Repeater-Builder@yahoogroups.com
>Subject: RE: [Repeater-Builder] Re: Duplexers
>
>What size wire does
peater-
> [EMAIL PROTECTED] On Behalf Of Ron Wright
> Sent: Saturday, September 01, 2007 8:02 PM
> To: Repeater-Builder@yahoogroups.com
> Subject: Re: RE: RE: RE: RE: RE: Re: Re: RE: [Repeater-Builder] Re:
> Duplexers
>
> Jeff,
>
> The question is way off base. No on
ps.com [mailto:Repeater-
> [EMAIL PROTECTED] On Behalf Of Ron Wright
> Sent: Saturday, September 01, 2007 8:49 AM
> To: Repeater-Builder@yahoogroups.com
> Subject: Re: RE: RE: RE: RE: Re: Re: RE: [Repeater-Builder] Re: Duplexers
>
> Gary,
>
> Yes the HP meter was spec'd to go b
[EMAIL PROTECTED]>
>Date: 2007/09/01 Sat PM 01:18:35 CDT
>To: Repeater-Builder@yahoogroups.com
>Subject: RE: RE: RE: RE: RE: Re: Re: RE: [Repeater-Builder] Re: Duplexers
>
>> I don't know where the confusion is...all coax and feedline
>> has a upper and
[EMAIL PROTECTED]>
>Date: 2007/09/01 Sat PM 01:40:02 CDT
>To: Repeater-Builder@yahoogroups.com
>Subject: RE: [Repeater-Builder] Re: Duplexers
>
>What size wire does it take to be self supporting at that length?
>
>'JK
>
>--- In Repeater-Bu
classified. They gave me about a 5 MHz spread. Was a fun project.
73, ron, n9ee/r
>From: Jim Brown <[EMAIL PROTECTED]>
>Date: 2007/09/01 Sat PM 03:10:50 CDT
>To: Repeater-Builder@yahoogroups.com
>Subject: RE: [Repeater-Builder] Re: Duplexers
>
>On the E
On the E-4 aircraft we delivered to the Air Force, the wire was about 1/4 inch
at the aircraft end and tapered down to around 1/8 inch at the drogue at the
far end. (to keep the wire from whipping around in the slipstream). We could
never deploy the wire over the US, but had to go down to the
What size wire does it take to be self supporting at that length?
'JK
--- In Repeater-Builder@yahoogroups.com, Ron Wright <[EMAIL PROTECTED]> wrote:
>
>... a C130 aircraft with 30,000 ft of wire hung out the back...
> I don't know where the confusion is...all coax and feedline
> has a upper and lower freq limit. Might try to learn
> something about this.
If what you say is true, can you tell me, using sound engineering and math,
why you can carry DC on coax if it has a low-frequency cutoff?
ri PM 05:59:28 CDT
>To: Repeater-Builder@yahoogroups.com
>Subject: RE: RE: RE: RE: Re: Re: RE: [Repeater-Builder] Re: Duplexers
>
>Are you sure that the impedance meter you used was speced for operation
>below .5 MHz?
>
>Yes all capacitors have inductance. Lead
31, 2007 7:12 AM
> To: Repeater-Builder@yahoogroups.com
> Subject: Re: RE: RE: RE: Re: Re: RE: [Repeater-Builder] Re: Duplexers
>
> Gary,
>
> To measure the impedance of the RG59 I used an HP impedence meter which
> displayed Z and phase. I use to use it to determine where caps bec
To: Repeater-Builder@yahoogroups.com
>Subject: RE: RE: RE: Re: Re: RE: [Repeater-Builder] Re: Duplexers
>
>I wonder what you were using to measure the impedance of the cable with
>below .5 MHz?
>Some cable especially rg59 types have copper clad steel center cond
On Behalf Of Ron Wright
> Sent: Thursday, August 30, 2007 10:48 AM
> To: Repeater-Builder@yahoogroups.com
> Subject: Re: RE: RE: Re: Re: RE: [Repeater-Builder] Re: Duplexers
>
> Gary,
>
> I've measured RG59 cable terminated into a 75 Ohm resistive load with a
> variab
y, August 30, 2007 10:54 AM
> To: Repeater-Builder@yahoogroups.com
> Subject: Re: RE: Re: Re: Re: RE: [Repeater-Builder] Re: Duplexers
>
> Gary,
>
> AC power line transmission theory is very different than RF. In RF
> radiation and propagation down the line follows a much diff
-Original Message-
From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] Behalf Of
Ron Wright
Sent: Thursday, August 30, 2007 11:48 AM
To: Repeater-Builder@yahoogroups.com
Subject: Re: RE: RE: Re: Re: RE: [Repeater-Builder] Re: Duplexers
Gary,
Coax also has
rge enough to act as wave guide. One will see upper freq specs will
be lower the larger cable.
73, ron, n9ee/r
>From: Gary Schafer <[EMAIL PROTECTED]>
>Date: 2007/08/29 Wed PM 09:23:57 CDT
>To: Repeater-Builder@yahoogroups.com
>Subject: RE: RE: Re: Re: RE: [Repeater-Builder
t;Date: 2007/08/29 Wed PM 09:03:50 CDT
>To: Repeater-Builder@yahoogroups.com
>Subject: RE: Re: Re: Re: RE: [Repeater-Builder] Re: Duplexers
>
>Transmission line theory is transmission line theory. It doesn't matter what
>the frequency is it all works t
uilder@yahoogroups.com [mailto:Repeater-
> [EMAIL PROTECTED] On Behalf Of Ron Wright
> Sent: Wednesday, August 29, 2007 9:37 AM
> To: Repeater-Builder@yahoogroups.com
> Subject: Re: RE: Re: Re: RE: [Repeater-Builder] Re: Duplexers
>
> The 300 Ohm or 50 Ohm is not part of the R in IR losses.
MX
> -Original Message-
> From: Repeater-Builder@yahoogroups.com [mailto:Repeater-
> [EMAIL PROTECTED] On Behalf Of Ron Wright
> Sent: Wednesday, August 29, 2007 9:32 AM
> To: Repeater-Builder@yahoogroups.com
> Subject: Re: Re: Re: Re: RE: [Repeater-Builder] Re: Duplexers
y hat and
> bow deeply in your direction.
>
> Randy
>
> W4CPT
>
>
>
> Original Message-
> *From:* Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED]
> ups.com] *On Behalf Of *Jeff DePolo
> *Sent:* Wednesday, August 29, 2007 11:28 AM
> *To:* Repeater
AM
To: Repeater-Builder@yahoogroups.com
Subject: RE: RE: Re: Re: RE: [Repeater-Builder] Re: Duplexers
> >There's a capacitor hidden in in my coax? Where? I can't
> find it, and now
> >I've ruined my cable looking for it :-)
> >
>
> Yep, whenever one has two
PROTECTED] On Behalf Of Ron Wright
Sent: Wednesday, August 29, 2007 10:32 AM
To: Repeater-Builder@yahoogroups.com
Subject: Re: Re: Re: Re: RE: [Repeater-Builder] Re: Duplexers
Ralph,
Transmission line theory for RF and AC power is totally different. In AC
power lines little is paid attention to as for
> The 300 Ohm or 50 Ohm is not part of the R in IR losses.
No, but the Z (300 or 50 or whatever) is what determines the *I* for a given
amount of power. The actual losses are due to that I squared, and the R of
the conductors themselves. Z is impedance. R is resistance.
> I think we are gett
> >There's a capacitor hidden in in my coax? Where? I can't
> find it, and now
> >I've ruined my cable looking for it :-)
> >
>
> Yep, whenever one has two conductors with spacing between
> them you got a cap. For a cap in coax might try looking for
> the conductors of center and shield...l
getting somewhat confused here,hi.
73, ron, n9ee/r
>From: Jeff DePolo <[EMAIL PROTECTED]>
>Date: 2007/08/27 Mon AM 08:55:41 CDT
>To: Repeater-Builder@yahoogroups.com
>Subject: RE: Re: Re: RE: [Repeater-Builder] Re: Duplexers
>
>> Jesse,
>>
>
>From: Ralph Mowery <[EMAIL PROTECTED]>
>Date: 2007/08/27 Mon AM 09:20:07 CDT
>To: Repeater-Builder@yahoogroups.com
>Subject: Re: Re: Re: RE: [Repeater-Builder] Re: Duplexers
>
>
>--- Ron Wright <[EMAIL PROTECTED]> wrote:
>
>> Jesse,
>
>From: Jeff DePolo <[EMAIL PROTECTED]>
>Date: 2007/08/27 Mon PM 01:57:13 CDT
>
>There's a capacitor hidden in in my coax? Where? I can't find it, and now
>I've ruined my cable looking for it :-)
>
Yep, whenever one has two conductors with spacing between them you got a cap.
For a cap in c
Gary K4FMX
_
From: Repeater-Builder@yahoogroups.com
[mailto:[EMAIL PROTECTED] On Behalf Of Jesse Lloyd
Sent: Monday, August 27, 2007 11:21 AM
To: Repeater-Builder@yahoogroups.com
Subject: Re: Re: Re: RE: [Repeater-Builder] Re: Duplexers
The whole problem here is the comparison be
K4FMX
_
From: Repeater-Builder@yahoogroups.com
[mailto:[EMAIL PROTECTED] On Behalf Of Jesse Lloyd
Sent: Monday, August 27, 2007 11:21 AM
To: Repeater-Builder@yahoogroups.com
Subject: Re: Re: Re: RE: [Repeater-Builder] Re: Duplexers
The whole problem here is the comparison between
> The whole problem here is the comparison between high
> impedance twin lead and low impedance coax. Is the
> difference of impedance really coax attenuation?
Maybe I'm not understanding the question. In the most general terms, loss
has no direct correlation to impedance because there are o
> It appears that the instant discussion has overlooked that
> there are three factors in the attenuation of transmission
> lines. They are the conductor losses, the dielectric losses, and
> also the optimum ratio of b/a = 3.6 for a coaxial line, which
> corresponds to a characteristic impedance
The whole problem here is the comparison between high impedance twin lead
and low impedance coax. Is the difference of impedance really coax
attenuation? If you kept I equal between twin lead and coax who would win?
Also impedance shouldn't change because of frequency (with the exception of
extre
It appears that the instant discussion has overlooked that there are three
factors in the attenuation of transmission lines. They are the conductor
losses, the dielectric losses, and
also the optimum ratio of b/a = 3.6 for a coaxial line, which corresponds to
a characteristic impedance of 77 o
--- Ron Wright <[EMAIL PROTECTED]> wrote:
> Jesse,
>
> Then why do twin feeders have much less loss than
> coax??? Skin affect is even more of a factor there
> due to the differences in the area of the outer
> shield in coax vs the twin feeders wire.
>
> Maybe it is because of the larger C cou
uilder@yahoogroups.com
> Subject: Re: RE: Re: RE: [Repeater-Builder] Re: Duplexers
>
> Loss in feedline has lots more to do with the LC in the cable
> than I^2R. If I^R were a major factor then frequency would
> not have much say in the equation. Skin affect is a factor,
> but then
> Jesse,
>
> Then why do twin feeders have much less loss than coax???
> Skin affect is even more of a factor there due to the
> differences in the area of the outer shield in coax vs the
> twin feeders wire.
The current in a 50 ohm cable is higher as compared to a 300 ohm cable for a
given p
ubject: Re: Re: RE: [Repeater-Builder] Re: Duplexers
>
>Well skin effect varies with frequency, there for the R is higher with
>frequency. I is constant, but R is not, so your power lost will vary with
>frequency because of I^2R and skin effect. This is why la
factor.
73, ron, n9ee/r
>From: Gary Schafer <[EMAIL PROTECTED]>
>Date: 2007/08/26 Sun PM 08:47:29 CDT
>To: Repeater-Builder@yahoogroups.com
>Subject: RE: Re: RE: [Repeater-Builder] Re: Duplexers
>
>
>Jesse is right about skin effect beinggreater a
Holy Cow!!
Get out your Smith charts!:-)
Thanks for the answers. Be careful what you ask for...
Thanks to Kevin at Repeater Builder as well.
IMHO still the best repeater info site.
73
Bernie Parker
K5BP
does all I squared R loss.
73
Gary K4FMX
_
From: Repeater-Builder@yahoogroups.com
[mailto:[EMAIL PROTECTED] On Behalf Of Jesse Lloyd
Sent: Sunday, August 26, 2007 3:32 PM
To: Repeater-Builder@yahoogroups.com
Subject: Re: Re: RE: [Repeater-Builder] Re: Duplexers
Well skin eff
ne freq and the same
> current at a higher freq the losses will be different. This was my point.
>
> 73, ron, n9ee/r
>
> >From: Jesse Lloyd <[EMAIL PROTECTED] >
> >Date: 2007/08/26 Sun PM 02:34:41 CDT
> >To: Repeater-Builder@yahoogroups.com
> >Subject: R
9:45 CDT
>To: Repeater-Builder@yahoogroups.com
>Subject: RE: [Repeater-Builder] Re: Duplexers
>
>Coax leakage is different than currents flowing on the shield though...
>
>I remember having some RG8 from Radio Shack with braid openings that you
>could probably fit a pencil throug
will be different. This was my point.
73, ron, n9ee/r
>From: Jesse Lloyd <[EMAIL PROTECTED]>
>Date: 2007/08/26 Sun PM 02:34:41 CDT
>To: Repeater-Builder@yahoogroups.com
>Subject: Re: RE: [Repeater-Builder] Re: Duplexers
>
>I^2R losses do change with
r VHF/UHF. The
> same can be said for many PL259 connectors and adapters.
>
> 73, ron, n9ee/r
>
> >From: Jeff DePolo <[EMAIL PROTECTED] >
> >Date: 2007/08/26 Sun PM 12:59:45 CDT
> >To: Repeater-Builder@yahoogroups.com
> >Subject: RE: [Repeater-Builder] Re: Dup
conductors due to much less surface area between the conductors.
73, ron, n9ee/r
>From: Jesse Lloyd <[EMAIL PROTECTED]>
>Date: 2007/08/26 Sun PM 01:08:49 CDT
>To: Repeater-Builder@yahoogroups.com
>Subject: Re: [Repeater-Builder] Re: Duplexers
>
>Braided co
Braided coax does radiate a little, there is no such thing as 100% braid.
Thats why in the cable TV industry they have to use double braided coax in
the headend, otherwise you can have a hell of a mess of stray RF in there.
Coax loss is due to I^2R losses and radiation (and connector loss but that
> Wait a minute Jeff... what about that crappy low cost silver jacket
> Super-flex Columbia branded coax I bought back in the 70's during
> the CB boom...
Coax leakage is different than currents flowing on the shield though...
I remember having some RG8 from Radio Shack with braid openings th
84 matches
Mail list logo
