[TowerTalk] Re: trouble shooting M2 T-Match

[K0FF]

To test the M2 coupling block/folded dipole driven element, VHF and UHF
beams:

Remove the shorting blocks, shorting bar and the balun. Measure zero Ohms
between center pin of N connector, one of the F connectors and one side of
the dipole. Measure zero Ohms between the other F connector and the other
side of the dipole. Infinite resistance between the two sides of the dipole,
and also no connection to ground anywhere.

First check the spring-pins  that make connection to the center conductor in
the N connector. These are easily bent or broken, and fail to make a
connection.

The dipole elements are made from aluminum. In order to solder the internal
wiring to them, a piece of copper tubing is crimped over (in the case of
solid rod) or inside of (in case of hollow tubing..earlier design). The
wires are then soldered to the copper.
One failure mode is that one of the soldered connections breaks. Easy to
fix..just take off the cap, remove the goo, and resolder. Another failure
mode is that the different metals  (AL-CU) don't make electrical connection
anymore, even though mechanically in contact. Sometime this can be cured by
running a large current through the joint (like from a car battery) and an
intermittent will either A) fuse itself and be good again or B) fail
totally. In which case you order another block/dipole from Mike.

Good luck, Geo>K0FF
-----Original Message-----
From: PKMST@aol.com <PKMST@aol.com>
To: vhf@w6yx.stanford.edu <vhf@w6yx.stanford.edu>
Date: Friday, June 09, 2000 8:40 PM
Subject: trouble shooting M2 T-Match


>hi every one, any body know how to trouble shoot a m2 t match with
machined
>aluminum block and n connector in one side and 2 f connectors in the other
>side. the old 20 yr old rusty hygain is beginning to look real good laying
in
>the weeds, hooked it up for the heck of it and it was perfect match go
figure
>any way 73,s and thanks to all that replied earlier. trying to make the
>contest but looking bad. Mark KE4JLE EM75
>------
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