[1000mp] Key Click Mod

[Bob Main]

It is not the number of components that I am concerned with.  I have built a
number of items from scratch and a LOT of Heathkits in my time.  It is
simply the complexity of the radio and the size of some of the components.
Oh well, guess I can make a trip to Trash Shack and get the parts and pulled
in my 200w soldering gun and give it a go.

Bob

----- Original Message ----- 
From: "Ian White, G3SEK" <G3SEK@ifwtech.co.uk>
To: <1000mp@mailman.qth.net>
Sent: Friday, January 09, 2004 5:16 AM
Subject: Re: [1000mp] Key Click Mod


> Earl wrote:
> >
> >"I noticed that the INRAD mod consists of 2 capacitors and a resistor
> >and appears to be simple to do.  The W8JI mod looks like it consists of
> >a couple more components and a nightmare to install.  (Probably not,
> >just seems that way.)  Why is there such a difference in the two mods and
> >which one accomplishes the task the best?"
> >----------
> >I first did the INRAD "keying improvement" mod to my MP.  It reduced
> >the clicks from +/-2500 Hz to +/-800 Hz.  Better, but still not good. I
> >then did the W8JI click mod and the clicks are now +/-300Hz.  I am now
> >satisified.
> >
> >The W8JI mod is NOT a nightmare to install!  Just as many screws and
> >nuts and plugs must be removed for either mod.
>
> Correct! It really is not difficult.
>
> >The W8JI mod just requires a
> >few more components.
>
> The W8JI mod can be simplified a little. Tom originally ran a wire out
> from under the RF board so he could experiment with the capacitor value.
> Since he found that 0.1uF works well enough in all cases, there's no
> need to run that wire. Simply solder the extra cap across the existing
> capacitor underneath the board, and put the board back as you found it.
>
> The IF board is even easier to flip over and solder on a wire.
>
> W8JI's other components connect to that wire. The two trimpots and two
> capacitors can be mounted on a piece of perf-board, next to the IF
> board. The perf-board can be fixed to the chassis by sticky foam pads -
> no holes required.
>
> The Inrad mod uses fixed-value components instead of the trimpots
> (values are given in the PDF on the Inrad website) and these will make a
> significant improvement. But as Earl and Bob say, you can make it even
> better using the trimpots.
>
> Just listen to the clicks on a second RX, and twiddle until it's clean
> as you can make it. The adjustments affect the 'make' and 'break' clicks
> differently, so use a hand key so you can hear the two kinds of clicks
> separately.
>
> Come on, folks - it's only five components. No metalwork, welding or
> heavy machinery required.
>
> Or if your eyes, hands or lack of experience genuinely prevent you, then
> surely you know someone who can do it for you?
>
>
>
> Earl said:
> >Without the mod, if the operator goes on CW in the CW portion of the
> >bands, his wide CW bandwidth violates FCC regulations, IMO.
>
> Or if the big stick doesn't work, how about your self-respect and your
> on-air reputation?
>
>
>
> -- 
> 73 from Ian G3SEK         'In Practice' columnist for RadCom (RSGB)
>                             Editor, 'The VHF/UHF DX Book'
> http://www.ifwtech.co.uk/g3sek
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