Posted by blackburst@aol.com on 01/10/57 11:44

Scott Dorsey wrote:
> blackburst@aol.com <blackburst@aol.com> wrote:
> >For rec.audio.pro:
> >
> >1) The wireless mic for the Telex stsem is lost, so they currently use
> >an AKG system , but the mic makes a "pop" when it is turned on or off.
> >They want to go back to the Telex. Two questions: a) What transmitter
> >do I need? It's a Telex FMR-450 at 614.700. I prefer either a
> >completestick, or a butt-end which can go on any stick. b) In the
> >booth, the receiver has two short antennas, but it's in a rack. Can I
> >replace the antennas with some that can be mounted outside the booth?
> >What model/mfr? They're screw on 259 type connectors. The system must
> >be rock solid under difficult circumstances, Pomotions manager in left
> >field, for example.
>
> You HAVE to buy another Telex. You cannot mix and match different
> manufacturers units because they all use different modulation and noise
> reduction systems.
>
> You can use any antennae intended for that band. Jerrold single-channel
> TV yagis used to be a popular choice.

A TV antenna? There are two short antennas on the unit in the rack,
rather hard to get at during my brief visit.

>
> >2) They want the PA to feed into a picnic area just beyond center/right
> >field. I can add an amp in the booth and run 70v through conduit and
> >mount them on light poles, but it's a difficult path, and the GM is
> >balking at the expense. he wants a wireess system. I'm considering a
> >transmitter in the booth and an all-in-one receiver/amp/speaker that
> >they can move at will. What units would you recommend? It will
> >basically bring announcements to an area about 75x50 feet.
>
> I think wireless is a mistake and gives you too many things to go wrong.
> Running a 70V system will wind up costing less in the long run even
> though the up-front cost is much higher. Is there ANY existing cabling
> that you could piggyback off of? Telephone circuits, old unused power
> wiring?

At a certain point on both field lines, the stands end, and there is a
retaining wall which goes from about 4 feet down to 4 inches, as the
ground slopes up. I see no existing cabling or channels. There IS an
electrical vault beside each light pole, but, the GM thinks it comes in
from off the street, the wrong direction.

>
> >3) The speakers at the adjacent conference center apparently crackle,
> >even with no program material. But I was not able to hear it today, as
> >there was a conference going on. I'm guessing the speakers are OK, but
> >something is getting into the amp or cabling.
>
> Almost certainly. Is there a wireless receiver connected to the thing
> which is active but squelched down? If so, turn it off when it is not
> in use.

I'll try that. I'm also going to switch the speaker connections to
another amp and see if the problem follows it.

>
> >For rec.video.production:
> >
> >1) A Sony 3-chip DVCAM feeds through a vertically mounted antenna
> >(about the size of a flashlight barrel, BNC connector) to a series of
> >DynaPix antennas, into a receiver, then onto the big CF screen. The
> >previous company removed 4 of the 5 antennas! The system never worked
> >well, as I understand the antenna is designed to be AIMED at the
> >DynaPix antennas, not vertical. Is there any more reliable system out
> >there, that can receive solid pictures from most any open area of the
> >stadium? THIS one, they're willing to spend a bit on.
>
> I don't understand this. Is this a single point-to-point link or is this
> a broadcast link? If you have only a single point to point connection,
> just use the right antennas and be done with it.

The camera goes to various locations on the field, in the stand, even
just outside the park. It has a camera-mounted transmitter with a
vertical antenna which, I understand, is supposed to be aimed. It is
pucked up by an array of 5 DynaPix antenna just below the booth (in the
stands behind home plate.) The link has picture breakup often.

> --scott
> --
> "C'est un Nagra. C'est suisse, et tres, tres precis."

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