Manufacturing ATU switches
 

Picking up a project that has been put down for 6 months - has
anybody got experience of manufacturing their own ATU
switches out of brass, either as knife switches or else as
ginormous banana plugs which then engage axially with
a sliding action?

I have conceived of a design for an experimental ATU that
allows changes of configuration (including the safety earthing
when not in use) using only 8 single-pole single throw switches,
into the most common configurations.

(I may have mentioned this before in this NG, sorry if so and
thus inducing ennui in my loyal-but-paranoid fan-club of CB types
who seem to hang on my every word)

"Airy R.Bean" wrote in message
...
Picking up a project that has been put down for 6 months - has
anybody got experience of manufacturing their own ATU
switches out of brass, either as knife switches or else as
ginormous banana plugs which then engage axially with
a sliding action?

I have conceived of a design for an experimental ATU that
allows changes of configuration (including the safety earthing
when not in use) using only 8 single-pole single throw switches,
into the most common configurations.

(I may have mentioned this before in this NG, sorry if so and
thus inducing ennui in my loyal-but-paranoid fan-club of CB types
who seem to hang on my every word)


I cant believe the amount of **** you come out with!

On Tue, 11 Jan 2005 12:52:27 -0000, "Airy R.Bean"
wrote:

I may have mentioned this before in this NG

Which ng? You have posted to two.
--
from
Aero Spike

On Tue, 11 Jan 2005 13:10:39 -0000, "Dominic G7NPW"
wrote:

I cant believe the amount of **** you come out with!

You might not like what Bean posts, and few would disagree with you,
but PLEASE DONT REPOST IT ALL JUST TO ADD A ONE-LINER.
--
from
Aero Spike

"Spike" wrote in message
...

SNIP

You might not like what Bean posts, and few would disagree with you,
but PLEASE DONT REPOST IT ALL JUST TO ADD A ONE-LINER.

Advice Taken, Thanks for pointing this out to me.

73 Dominic

"Spike" wrote in message
...

SNIP

You might not like what Bean posts, and few would disagree with you,
but PLEASE DONT REPOST IT ALL JUST TO ADD A ONE-LINER.

Oh and there was no need to shout at me I can hear you fine.

73 Dominic

On Tue, 11 Jan 2005 13:46:05 -0000, "Dominic G7NPW"
wrote:


"Spike" wrote in message
.. .

SNIP

You might not like what Bean posts, and few would disagree with you,
but PLEASE DONT REPOST IT ALL JUST TO ADD A ONE-LINER.

Advice Taken, Thanks for pointing this out to me.

You're welcome.

It's just that those who have killfiled Bean because they don't want
to see his posts may well killfile you for that same reason, shoud you
continue to repost the whole of his postings. Usually it's only
necessary to quote a word or two from him in your reply, as he hasn't
said anything new seemingly for ages......
--
from
Aero Spike

"Starr" wrote in message
...

you certainly enjoyed constructing your web site didn't you? :)

Yep, Better then Corro & Eastenders.


--
Regards Dominic G7NPW

Derby Echolink Gateway. Number 92369

www.derby-radio.co.uk

"Airy R.Bean" wrote -
Picking up a project that has been put down for 6 months - has
anybody got experience of manufacturing their own ATU
switches out of brass, either as knife switches or else as
ginormous banana plugs which then engage axially with
a sliding action?

I have conceived of a design for an experimental ATU that
allows changes of configuration (including the safety earthing
when not in use) using only 8 single-pole single throw switches,
into the most common configurations.

==================================

The trouble with as many as 8 single-throw, high-current, high-voltage
switches in a tuner, is the stray inter-component wiring and inductance and
capacitance they introduce.

Even with a minimum number of, or no switches, it requires TWO independent
tuners, in separate boxes with separate coaxial connectors, to cover the
range 1.8 to 30 Mhz with reasonable power efficiency.

You need practical experience by building one or two to see how they
perform. Try again and then come back!
----
Reg.

"Reg Edwards" wrote in message
...


The trouble with as many as 8 single-throw, high-current, high-voltage
switches in a tuner, is the stray inter-component wiring and inductance
and
capacitance they introduce.

Even with a minimum number of, or no switches, it requires TWO independent
tuners, in separate boxes with separate coaxial connectors, to cover the
range 1.8 to 30 Mhz with reasonable power efficiency.

You need practical experience by building one or two to see how they
perform. Try again and then come back!


Would a solution based on two, contra-rotatinng "roller coasters" not be
better? This would enable a true balanced ATU to be made, offering a wide
matching impedance, and, with motorised capacitor, avoiding switching all
together?

Making a suitable capacitor is straight forward. The rollor coaster former
will turn up on a lathe nicely (I've made a similar former from PTFE in the
past). The rest of the mechanics are easy enough.

--
Brian Reay
www.g8osn.org.uk
www.amateurradiotraining.org.uk
FP#898