does anybody remember who was building generic front panels - - long response

From: woodelf <>
Date: Wed Feb 2 02:40:37 2005

Gooijen H wrote:

>An other difficult part are indeed the switches.
>First, I must say that I *never* had the intention to make a 1:1 replica of
>frontpanel. My museum is already quite full as it is (with even more to
>I searched for paddle type switches, normal and spring-loaded. Not easy, but
>the ones I found can still be ordered, but they are indeed rather small: the
>lebgth of the paddle is approx 12-15 mm (IIRC) and the width is 10 mm. If
>have thick fingers the size is really small.
>The size of the switches determined the total length of the frontpanel which
>is still 36 cm. The height is then set by proportion compared to the real
So what are the part numbers of the switches you used?

>As Ethan said it: you must make the size of the switches and the frontpanel
>proprotional to eachother. If you want the frontpanel to be as close to the
>original as possible it must be 19" wide. Small switches is definitely not
>what you want in that case!
>The ones used on the FP6120 look bigger than the C&K ones that I used, but
>the finishing touch is of course to get them in the correct color.
>More work, but I said it on my website: the end result is very depending on
>the effort and time you spend on the frontpanel.
In my case I have *NO* tool s of any kind or the practical knowlage
of the metalworking
to be done so I my case I have get other people to do the work so front
panel express is
most likely the way I will go.

>Rich mentioned the price tag. He is correct that you must do the math.
>The switches are easily costing $4 a piece, and for a PDP-11 or -8
>just the switches will set you back some $80 to $100.
$4??? I have been looking at switches and they range from 25 cents (
surplus )
to $25+ each and you still have the display to worry about. Also it
seems that
you have more display options than just leds but that is more $$$ yet.

>The problem with designing a PCB for the LED's and switches is not the
>electronic part, as said in the beginning of this e-mail :~) The design is
>simple and straight-forward *if* you have the dimensions of the switches
>are going to be used. Making a frontpanel PCB is only useful if you know
>before how many are going to be wanted (and bought!) *and* you know for sure
>that the required amount and type of switches is available.
>Note that you *still* need (metal) work before you start soldering the
>to make sure that they line up perfectly. If you just solder the switches in
>the PCB you will see that you could get them lined up better. I guess that
>you get solve that by soldering only *one* pin of all the switches, and then
>line them up using the soldering iron and three hands :~)
In my case I belive PCB's are a better option than wire wrapping. In my
case I have more
time than skill so doing computer work is easy as compared to mechanical
By using CPLD's I hope to get the cpu and memory and I/O on one board and
just have the front panel I/O come out. The only real problem with me doing
a hardware version of the 8 is the complex hardware for extended
memory and
hardware details that you don't expect. Since the CPLD's are
reprogramable I could
do almost any small computer that is not micro-programmed or have lots
of registers.

>Same story goes for the LEDs, but depending their visibility (when they are
>you get get away with a less than perfect alignment ...
Has anybody tried using the white leds for displays?

>One thing you must consider -- and I forgot that in my construction!!
>The frontpanel plate will have some distance to the plate where the switches
>mounted on - or if you like: the PCB where they are soldered on.
>Keep that distance in mind when you solder the LEDs (or lamps). Try to get
The other chicken and the egg problem is knowing just what to buy, since you
practicaly have to build it first to get what ideas and parts you need.

> thanks for the nice feedback on my project,
>- Henk, PA8PDP.
Received on Wed Feb 02 2005 - 02:40:37 GMT

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