Re: Handic Software Multi-Switch

Den Thu, 26 Jul 2018 19:16:48 +0300 skrev Ville Laustela
<ville.laustela@gmail.com>:
> Hi all.
> 
> I came into posession of a swedish-made serial switch-box for the C64
> (share one devices between up to 8 computers). Very much like this
> one:
> https://www.richardlagendijk.nl/cip/mix/item/handic_vic-switch/en and
> in a nice shape with original box.
> 
> However my unit has some differences to images I found online:
> 
> - The sticker on the front says Multi-switch (not Vic-Switch), and
> the box says it’s for Vic-20, C64, 16, Plus/4 or 128 machines.
> (However the two-page manual only speaks of Vic-20 and C64)

Does the manual actually say C64 or does it say "VIC-64"? For some
reason Handic which were the importer when C64 were new called it
VIC-64.

> - My unit does not have AC mains input, but a barrel connector that
> looks somewhat bodged-in. It’s center negative. (The manual shows a
> mains input)

I assume that this is so they didn't have to get it approved by all
different test institutes which back in the days were different in
almost every country.

> - Inside the unit there is an extra PCB mounted over the mainboard
> and a big ribbon cable connecting it to the bottom side of the main
> board.

Like Mike I think this is a solution to make C128 burst mode work.

I think that the main reason for there not being any replicas of VIC
SWITCH is that the original design doesn't work well with burst mode.

It would be really nice if you could take a photo of the solder side of
the extra PCB and preferable also measure where the connections under
the IC's go (i.e. pin 4/5/6 on the rainbow colored flat cable)

Judging by the IC's I assume that the two 4051's connect the extra
"burst" pin of one of the IEC computer ports (pin 11-18 on the flat
cable) to the common/drive IEC port (pin 19), just like all other
signals are swithed on the main board. The 74LS30 is a 8 input NAND
gate which probably just senses if any of the computers pull the
"burst" signal low. The 74LS125 is a bit strange here though, it
contains four buffers with individual three state control. It seems
like two of it's pins, not sure which, goes to one of the ICs on the
main board that's nearby the LEDs.

> - Inside the unit there is no mains transformer as in images online.
> The rectifier is on the board, but the ac side of it is not connected
> at all, and the DC input is wired straight to the DC side of it,
> going to the two parallel 470uF/25v electrolytics. Then the power
> rails continue to the 7815 and 7805 regulators’ inputs.
> 
> I got the unit without power supply (also non-tested due to that).
> Looking at the board it seems that I should use a DC power supply of
> something between 15v - 25v. Does this sound correct?

25V might be a bit excessive, but yes, anything in that range that also
won't overheat the voltage regulators would work fine.

> Here are some pictures of my unit:
> https://postimg.cc/gallery/2jv4u1jjw/

Thanks!

A bit of back story: Datatronic were the importer of Commodore, and
Handic their daughter company for selling the consumer computers (i.e.
Datatronic sold the PET's while Handic sold VIC-20 and C64). They
however lost their deal with Commodore in early 1985, maybe due to that
Datatronic had bought the PC manufacturing company Sirius/Victor which
probably were seen as a competitor by Commodore, or maybe Commodore
just changed their policy. Datatronic/Handic continued for some years
selling Victor PC's. But as they already had developed some hardware
and software for the Commodore 8-bit computers, they continued to sell
them instead of just scrapping it all. It's only recently that I were
made aware of that there were (at least adverts for) C128 versions of
their Calc Result spreadsheet and Word Result word processor software,
and now you show a piece of hardware that shows that there were at
least some minor hardware developement done. I guess that their
business case must had been that they already had the main boards
produced (empty boards or populated with components) and might aswell
do something to sell them instead of having to scrap them. Adding burst
mode made them more future proof and removing the mains transformer
made it possible to sell them more or less world wide.

I'm not sure where Datatronic/Handic sold their stuff except for Sweden
and IIRC Norway. I think I've read about then having some daugher
company in the Netherlands and/or Belgium. They printed an ad for PET
accessories in the early 80's in at least three different english
language computer magazines, showing their SCIP interface IEEE-488 <->
rs232, an internal RS232 interface for PET, their PET SWITCH (the
IEEE-488 equalient of a VIC/Multi Switch, but with separate small
client boxes for each computer) and their FORTH implementation (and
maybe more software, can't remember). Not sure if that made any impact
on other parts of the world. Also it has come to my attention that some
of the software they sold under their own brand here in Sweden were in
fact OEM versions of foreign software.


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