On 27/05/2017 13:24, Dave Liquorice wrote:

I must admit I'm inclined to agree, I think the price difference 12
16 24 will be a big influence, Do unused outputs need to be
terminated?

No


(if they're labelled the labels will all be wrong).

I'll be labeling them, the labels will be right. B-)

You might get in a muddle. I always did.


Do you happen to know how these things work internally? Is it just a
single output amp, followed by say 30 dB attenuators to each output
port (giving 60 dB between ports),

The one I took apart on a rainy day had stripline tap-off units on a
PCB. One long track with a lot of short tacks very close to it. The
little ones were grounded via a 75ohm resistor at one end and the other
end went to the output port.

or individual amps per port? As
you say a single port can die that would indicate the latter as there
ain't much to go wrong with an attenuator.

It's the switching between band and polarisations that goes wrong,
usually sticking on one permutation or sometimes two. Also you get bad
connections (hairlines) on the output sockets when they connect to the PCB.

When an amp goes down you lose one permutation on every port.

The commonest fault on multiswitches is the PSU. Luckily that's fixable.
They really don't like emp from lightning.

Bill