Satgen 128   Odd Jobs versus Digital Constipation by GM4IHJ 8Sep 91

For many people, what they buy from the amateur radio shop has to be
perfect. Unfortunately this is not always the case, and an area which
seems to give most trouble is antennas which perform poorly at satellite
frequencies. So it may be useful to give details of my recent minor
activitiesin this field.
1. On its first test, the antenna performed badly. I got out the Standing
Wave Ratio Meter and discovered it had an SWR of 3.2 to 1 at 435MHz
2. Examining the feeder to antenna connections there was no evidence of
any attempt at matching, although I could see that the coupled pair of
folded dipoles in parallel would be nearer 100 or 150 ohms - somewhat
above the 50 ohm unbalanced coax recommended. So I had to improve this
match. I decided to use an easy solution for my first try and put in a
coax 75 ohm quarter wave matching connector between feeder and antenna. I
had plenty of 75 ohm cable but my grid dip meter does'nt go above 250 MHz.
So I grid dipped a quarter wave at 217.5MHz, cut it into 2 equal halves
and used one of the halves to connect in between feeder and antenna.
Tested on a short cable 1.2 SWR. So I put it up on the roof through 40ft
of cable and it is showing 1.1 SWR. Purists may shudder. But it works
3. Having got my new antenna to perform . I next had to be sure it was
pointing in the correct direction. I use an old Army marching compass with
floating needle for this. The magnetic pole is some way removed from the
North Geographic pole. So magnetic compasses do not point at due North
they point west of north in UK.. The difference being called the magnetic
VARIATION for you location. You get the value of variation from the
Ordnance Survey map for your area. For June 91 in Mid Scotland it turns
out to be 5.5 degrees west. So I tested my rotator and antenna by ensuring
that when I directed it south it pointed at 185.5 degrees magnetic .Taking
care not to stand anywhere near my neighbours highly magnetised welded
bar, iron railings as I measured it. End result of the above was that
access to the satellite of my choice which had been difficult is now quite
easy.

SPECIAL PLEA.....PLEASE PLEASE PLEASE  Satgen bulls are as requested, 
addressed worldwide. Do not re address and re issue GM4IHJ Satgen bulls
back into the UK network or any feed to that packet network. This week saw
the stupid situation where 5 duplicate copies of Satgen 126 were on UK
bulletin boards simultaneously .Surplus bulletins clog the network and
infuriate other users. Multiple regurgitation of this sort produces
communications constipation. Spanish (1), English (2), and American (3) in
number culprits are requested to try using a little common sense in
future. 73 de John GM4IHJ@GB7SAN