Yeah, I gots an old Motorola tube repeater with a Sensicon RX in it
and a 50 watt light bulb. Just tune for maximum brightness, Right?
On 4/22/05, Coy Hilton <[EMAIL PROTECTED]> wrote:
>
>
> Good Luck!
> Do you have any equipment to tune it with after you build it?
> Any how, Have you done a search for "2 meter duplexer construction"
> from your favorite search engine? If not try it. You will find a few
> good write ups including one on repeater-builder dot com site there
> is even one out there on building a set of BpBr from I think 8 inch
> copper pipe with color photos that really works.
> 73
> --- In Repeater-Builder@yahoogroups.com, DCFluX <[EMAIL PROTECTED]> wrote:
> > Ok, I have some theroies, but I need confirmation from someone
> that
> > is like good with math and formulas and stuff as you know I
> flunked my
> > high school pre-algebra class.
> >
> > Anyway I want to make a 2 meter duplexer economy style as the
> person
> > who is building the repeater cannot afford a trip to the Zoo let
> alone
> > a set of big cans. So I wan't to build either a 6-pack or a 8
> block
> > of cavitiys, like the UHF mobile duplexers only longer. 2 - 3dB of
> > insertion loss would be acceptable
> >
> > Doing some coaxial theory and using air as a di-elelctric. Will an
> > inner conductor with a outter diameter of 3/8" and the outer
> > conductor with an inner diameter 1" yield 70 ohms impedence? If
> not
> > what would the impedence be? And what would the dimensions of the
> > outter conductor need to be if the inner is 3/8"?
> >
> > The present idea of mechanical construction is to use 3/8" copper
> > solid ground rods cut to length for the inner conductor and
> encasing
> > in either 1" or 1 1/4" pipe. Then there would have to be a bushing
> > fabricated that has allen set screws to adjust the length of the
> > center conductor. This design should be ideal for any frequency
> > asuming the materials are big enough.
> >
> > I am planning for a Notch only style duplexer to keep costs down.
> > Without design software I cannot acurately predict band pass or
> BpBr
> > "Q" if the cavities have more than one connector.
> >
> > Also loop construction ideas are welcome as I currently am planning
> > BNCs on the top with 12 ga straight down from the top and soldered
> to
> > a hole in the side of the can.
> >
> > I am also considering a Teflon disc at the end of the tuning rod to
> > act as a spacer for mechanical stability if the set is lied flat.
> >
> > On 4/22/05, Mathew Quaife <[EMAIL PROTECTED]> wrote:
> > >
> > > Yes I agree on that one, I locked them down and one of them
> moved on me,
> > > check each one indivually.
> > >
> > > Mathew
> > >
> > >
> > > Dave VanHorn <[EMAIL PROTECTED]> wrote:
> > >
> > > At 07:22 AM 4/22/2005, Mathew Quaife wrote:
> > > >If these are like my TX/RX duplexers, the slighest movement of
> the
> > > >tuning rods makes a huge difference, especially on the tx
> > > >side. retune would be a good idea. Take them slow, they are fun
> to
> > > >tune. Enjoy!
> > >
>
> Yahoo! Groups Links
>
>
>
>
>
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