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October 3rd 04, 12:25 AM

PAMNO (N2EY) wrote in message ...
In article ,
(Brian Kelly) writes:

time base and presets. Could be used with almost any rig. Hooked it up
to a
75S3

I'll bet I know where the S3 came from . . .

W3ABT, now N3KZ

.. . . I couldn't have missed . . !

single-sided boards dammit! Which all homebrewers could do then. Dunno
how you did yours but there were complete PCB "kits" available from
Kass and Radio Shack when I did mine.

My method was very simple - and I did double-sided ones.

1) Lay out both sides on grid paper
2) Lightly center punch holes on both sides
3) Cover both sides with transparent packaging tape
4) Use Xacto knife to cut out non-copper parts of tape
5) Ferric chloride bath to etch
6) Wash, remove tape
7) Drill through holes

Some what crude looking but they all worked. To save layout time, I made each
counter decade on one board, then wired the decades together.

My method was quick/n/dirty but it worked. No busted traces either.

Sounds OK for small one-off boards but there are some downsides to
that method. The biggest I see is that you can't get multiple boards
out of a single layout, you have to do the "artwork" for each board
which is the intensive labor part of DIY PCBs. The stripline SWR
bridge I built worked quite well and as a result I got several
requests for copies of the board and I was able to churn 'em out
pretty quickly by simply reusing the "negative". Which I also was able
to keep on file for possible use again.

An advantage of using the commercially-supplied to-scale transfer
patterns for chips and transistors was high accuracy and density
without having to draft and cut them manually. Which is a *lotta* work
if you did a big board like the K3JH keyer which used a couple dozen
chips. Solder-patching the traces was a 5-10 minute per board
no-brainer, I did it to all traces as "insurance". In the end both
approaches have their applications.

old crap. I have a yen now to build a couple more widgets using
homebrewed PCBs but so far I have not been able to find the board
stock or chemicals in hobby quantities.

I have the board stock. Ferric chloride is a different matter...

Bare double-sided board stock is readily available but sensitized
board stock ain't and neither are the chemicals. No doubt it's just a
matter of Googling around to locate the stuff. Maybe the technology
has improved to the point where DIY "board burning" is now a piece of
cake.

I fed the aformentioned dumpster a *shoebox* full of those old 7400
series chips . . .

They were da bomb in their time but today it would be easier to do it other
ways.

Right.

Or just do a mechanical dial...

Why would I do that when shaft encoders and freq counters are a
helluva lot smarter way to go??

It's all there. Main point is simply that the output of many synthesizers isn't
nearly as clean as what comes out of xtal or self-controlled oscillators of
good design. Which is why this wasn't a problem in, say, a Ten Tec Corsair 2.
.. . . .

The upshot of all of it is that in real-world hamming, we often have
to deal with bands full of strong signals, yet we want to hear the
weak ones.

That leaves Sweetums and his half-vast "experience" out. Long-haul
military HF comms are channelized and if a station is weak they just
twist the Variac clockwise. 40kW with rhombics just to push RTTY from
Tokyo to the west coast . . SPARE me . . !

Just a different environment. Army of Occupation takes over JA in 1945, one of
the first orders of business is good comms back to DC and Arlington. Pick out a
good site, put up the poles, haul up the diamonds, fire away. All on the
taxpayer's nickel. Well spent money but has little to do with the reality of
self-funded avocational radio.

Right on the money. As if Sweetums ever sank dime one of his own wad
one into any "station he operated". Fact is that he wouldn't have done
any of it if us taxpayers hadn't paid him to do it . . . Hell, we even
paid him to trudge thru the University of Monmouth Vo-Tech Division.

Sponge. Bleh!

all at once raise the apparent noise floor of their *modern*
transceivers, in part due to phase-noisy oscillators in the
contest-haters equipment.

"If ya can't take the heat go up the band!"

Point is, they *could* coexist with better equipment.

There is no way that any guy/gal even with the world's quietist rcvr
and offscale BDRs and IMD3s is gonna "coexist" and ragchew with
anybody on 7.020 at sundown and beyond during the two big CW DX
contests, just isn't possible in any even remotely practical scenario.
Try it the last weekend of November. Move up the band or go to 30M.
'Way up the band . . .

btw - the way I'd solve the problem would be to email you for the
solution.

. . . boink . . POINT!

"Wouldn't it be easier for *me* if *you* did it?"
.. . . .

Like I said - don't reinvent the wheel....

You do your things, I add my things and we get the job done. But
Sweetums can do it ALL . . . of course his history proves otherwise.

I run a LISP
rountine in Autocad to come up with the cross-sectional properties

.. . . .

Nice! But I prefer Microstation...

Lemmee know when you get yer home installation of Microstation to spit
out the plane and torsional moments of inertia of a tower section.

73 de Jim, N2EY

w3rv