On 03/06/2012 04:35 AM, Gergely L?rincz wrote:
I wonder, which one is more reliable, wire-wrapping or
soldering on a
vero/stripboard? I fancy learning wire wrapping but it's expensive.
I use spool
wire, a few colors, hand stripper of the automatic type,
and a OKtool manual (you squeeze to spin the bit) and good gold tail
sockets.
Even now it's less expensive to equip to do that than buy the soldering
gear and
all.
Reliability, I have panels I made up back in the 70s still running
(including an ELF).
Its easier to train an operator to do wirewrap and recognoze a good wrap
than
soldering. No power needed to make up a board so the kit to do it is
portable.
Oh, there are no RoHS issues with wirewrap (no lead, no fluxes).
The largest system done with wirewrap by me was about 200 pcs TTL and
bit slice. It was a complete custom processor with ram and IO.
Allison
On 6 March 2012 02:14, allison<ajp166 at
verizon.net> wrote:
> On 03/05/2012 04:48 PM, Ethan Dicks wrote:
>
>> On Mon, Mar 5, 2012 at 4:15 PM, allison<ajp166 at verizon.net> wrote:
>>
>>> Ethan Dicks wrote about the COSMAC Elf:
>>>> It's certainly true that the 4016 and 4066 have differences in their
>>>> characteristics. However, in the simple way in which it is used in the
>>>> Elf,
>>>> I can't see how it would make any difference. I can't say that
I've
>>>> actually tried it, though.
>>>>
>>> I have no difference.
>>>
>> I was told by the engineer who made the Quest SuperElf that he had a
>> problem subbing 4066s for 4016s. He was rather insistent there was a
>> problem. I have not tried it myself, either. My breadboard Elf and
>> my Quest Elf have 4016 switches.
>>
>> That may be the super elf. There is one oddity of the 1802, if run at
> higher speeds
> the timing of the control signals tend to skew badly. Also like all CMOS
> voltages
> at the pins are critical. I found the 4066 to be better, it's the same as
> the 4016
> but the series resistance of each switch is lower and the rate is can
> switch
> on or off is a bit faster. I've used both with no issue but I'm fussy
> about the
> timing and clock rates.
>
> Like any CMOS system get the ground and power well bussed and clean.
> It's tolerant but some parts can throw spikes when they switch that are
> nasty.
>
>
> that and also making sure all the wires go where they are supposed to.
>> Indeed. That was my problem on my Popular Electronics Elf.
>>
>> Wire wrap has always looked like a bowl of pasta to me. Even my own
> work.
>
>
> I've built many of the COSMAC ELFs over the years and still have my wire
>>> wrapped original, a
>>> QUEST PCB version and a few more wire wrapped variants. I made a version
>>> of
>>> the ELF on S100.
>>>
>> Nice.
>>
>> It's one of those CPUs that can be almost called an attractive nusance.
> ;)
>
> One thing I've not done yet is build a software compatible TTL or CMOS SSI
> version of the 1802 from the ground up. I think a 4 2901s could do th bulk
> of the registers and D nicely.
>
>
>
> I also have the EELF and ELF2000. It was a simple and very non-critical
>>> CPU to build up and make work.
>>>
>> Yep. I've built those, too. I just pulled out my Elf2K this weekend.
>> I need to re-do the switch plate label - somehow a drop of oil got
>> onto the paper and left a stain.
>>
>> I like my EELF as it's the whole stack with 8x24 video board. It ended
> up in
> an old Atlantic Research RS232 line monitor box with a nice 5" monitor. So
> the whole result with a PS2 keyboard is very portable though for AC power
> only. I need to build a power supply so it can run on a 12V source as
> there
> is room for 7AH battery inside..
>
>
> Of all the 1802 is the most interesting as it's
>>> not unlike the PDP-8 in that its
>>> simple to the extreme yet still useful.
>>>
>> Agreed.
>>
>> There's one thing I can do on my Elf2000 that I still can't do on a
>> PDP-8... play Zork.
>>
>>
> But consider this it was lunar lander and a few other games on PDP8
> ( or PDP12) that got the games thing going. Having played lunar lander
> with analog inputs on a vector monitor, I can say it's fun.
>
> Allison
>