From: Tony Duell <ard(a)p850ug1.demon.co.uk>
>I read somewhere that a piece of coke (the fuel, not the drug, OK :-))
>was used by POWs in the second world war as a detector. Using much the
>same cats whisker arangement as with the galena crystal. Might be worth
a
>try.
I will work but you want to find a peice that has really been fired and
has a
bit of rainbow color to it. IT's the contaminating oxides and all that
makes it
work though germainium is better.
>I would recomend getting the set working with a germanium diode first.
>Then, when you know the coil, tuning capacitor, headphones, aerial,
>earth, etc are OK, try the home-made detector.
Good way to go.
Allison
Can anyone point me to a good website about the Motorola 6800 (6800, not
68000)? I'm designing a simple computer around it, and need some info.
Thanks,
Owen
>That's interesting, there was an Appletalk hardware/software solution for the
>Amiga which was called... Doubletalk. It existed both as an external box for
>A500s and a Zorro card for the big boxes.
There was also the Emplant Deluxe with it's Localtalk ports, which I
used to connect my A4000 up to various Mac's. I never ran it as the Emplant
emulator but as a hardware extension of Shapeshifter's emulation.
Jeff
Speaking of the fastpath4 boxes, is anyone interested in two of them? I have
no interest in them right now. Prefer trades for IBM stuff, primarily PS/2.
Extra credit given if anyone can find me a Serverguard card for a PS/2.
In a message dated 3/30/01 1:34:46 PM Central Standard Time,
ethan_dicks(a)yahoo.com writes:
<< --- Mike Ford <mikeford(a)socal.rr.com> wrote:
> >--- Mike Ford <mikeford(a)socal.rr.com> wrote:
> >
> >I take it you resolved the issue of ROM code, driver software, etc. I
still
> >have that Fastpath4 sitting idle, waiting for the chance to put it to use.
> >
> >Any pointers on how to get it up and active?
>
> RTFM ;)
Love to. Need the FM.
> The FastPath is the most powerfull of the boxes that I know of, supporting
> the bridging of a complete localtalk LAN to a ethernet network, with both
> Appletalk and TCP/IP support among other features.
Perfect.
>>
I recognized a CRT tube at the local surplus place (R@RE NEW IN BOX! :-)
that looked like the CRT from a VT320 and I bought it ($2.14 including
tax), took it home and opened up my worst VT320 (this is one I had already
tweaked the internal "brightness control" so that I had enough raster to
see it) and sure enough, same Phillips part number. So I carefully
disassembled the VT320, removed the old tube, put in the replacement tube,
and voila` a nice bright VT320 with no screen burn at all. Alas it was yet
another amber tube, I really wish I could find some green tubes which I prefer.
Anyway, yet another piece of classic equipment, brought back into peak
operating efficiency.
--Chuck
On March 30, Tony Duell wrote:
> IMHO yes. Not the _original_ type, but a crystal set none-the-less. It
> uses equivalent components in the same circuit. And some germanium diodes
> (at least over here) appear to have a crystal and catswhisker in them.
Same over here...some silicon diodes as well. That's a
point-contact electrode for the anode if memory serves.
> Some old service manuals (I am showing my age now), used CRxx as a
> designation for 'semiconductor diode' in the parts lists and schematics.
> I always assumed CR stood for Crystal Rectifier.
CR does indeed stand for Crystal Rectifier. At least in the stuff
I've seen over here..
-Dave McGuire
Nope, the Sun video connectors are called 13W3's.
At 09:46 AM 3/30/01 +0100, you wrote:
> > It's video, and the official designation is PITA-23. :-P
>
>ha ha - ditto on the DA26 my Xterm uses - trying to find a connector for
>that was impossible. Ended up soldering a PC VGA connector to the board via
>a short bit of cable and using that instead :-)
>
>What about the Sun monitor connectors with the embedded 3 connectors for RGB
>- do they still fall under the same D-type categorisation?
>
>cheers
>
>Jules
On Mar 29, 19:05, Tony Duell wrote:
> I can't think of a 405-line only (as opposed to dual-standard 405/625
> switchable) portable with an isolated chassis (and presumably transistors
> at least in the signal stages?). I don't suppose you can remember the
> manufacturer, can you?
Nope, I can't even remember the nationality :-) Maybe I'm remembering
wronly about it being single-standard, but I don't think so. And I don't
recall any transistors. I *think* it was isolated-chassis, but I also
remember adding fairly high-voltage non-polar caps to the video input.
About the only thing I can remember is that it was a wooden case with
channel selector and ON/Volume (I think) on the top, and finished in
tasteful dark green leatherette.
Unfortunately I've nothing left from that set now -- the top few lines of
the display were never very stable on the Sorcerer (partly my kludge and
partly the Sorcerer's video signal not being quite right) so we parted
company when I bought a proper monitor.
--
Pete Peter Turnbull
Network Manager
Dept. of Computer Science
University of York
>
> Sure, albeit a less "authentic" one. I've always heard that
>germanium diodes are better for this (does this have something to do
>with their forward voltage drop of 0.3V vs. silicon's 0.7V?)...like
>the venerable 1N34A.
>
> -Dave McGuire
>
Yes... A silicon diode will require a stronger signal to overcome the .7
volt threshold.
Since we've already violated the purist aspects by using a semiconductor
diode, you could use a battery to apply a forward bias to the diode. In this
model, the signal doesn't need to overcome the entire .7 volt forward bias
voltage and makes a radio that is MUCH more sensitive.
Steve
_________________________________________________________________
Get your FREE download of MSN Explorer at http://explorer.msn.com
