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Possible to share one ADB keyboard among two Macs?
Posted by: krishnadraws on 2020-03-14 07:18:29
Is there an ADB keyboard switcher available that will let me use one ADB keyboard / mouse between my two classic 68k Macs? 

Posted by: superjer2000 on 2020-03-14 08:11:44
I had meant to post this a while ago - I had been looking for this exact same thing and after much googling, found this:  https://www.pccables.com/search?q=30061

It was way less expensive than what I found on eBay (especially after shipping) so I ordered it.  It arrived really quick (to Canada even).  I buzzed all of the lines to make sure everything was connected properly (no shared grounds etc.) and have been using it for the past couple of months.  Works great to switch between my IIgs, SE/30 and Centris 650...

Posted by: badCaps on 2020-03-14 09:49:19
I had meant to post this a while ago - I had been looking for this exact same thing and after much googling, found this:  https://www.pccables.com/search?q=30061

It was way less expensive than what I found on eBay (especially after shipping) so I ordered it.  It arrived really quick (to Canada even).  I buzzed all of the lines to make sure everything was connected properly (no shared grounds etc.) and have been using it for the past couple of months.  Works great to switch between my IIgs, SE/30 and Centris 650... 
Any caveats or does it work as expected?  I would have expected that design is the equivalent of unplugging and plugging in your keyboard which I thought was not supported on most Macs. 

Posted by: ArmorAlley on 2020-03-14 10:23:53
I know of 2 KVMs (keyboard,video, mouse) for ADB macs: Dr. Bott's & Black Box.

The latter is rackmounted. I have seen 4-, 6- and 10-port varieties. They are heavy and bulky. The Dr. Bott's are heavy and compact.

My 6-port Black Box has the nr. 724-746-5500 on the front.

Posted by: superjer2000 on 2020-03-14 11:48:22
Any caveats or does it work as expected?  I would have expected that design is the equivalent of unplugging and plugging in your keyboard which I thought was not supported on most Macs. 
As I posted it works great (therefore no caveats and it works as expected).  I'm not live switching - I only use one machine at a time so I switch to the machine I'm using and turn it on). As you might guess, when I want to switch, I turn that machine off, turn the dial and turn the next machine on.  I'm not sure why that would cause any concern?

Posted by: Unknown_K on 2020-03-14 12:56:11
I know of 2 KVMs (keyboard,video, mouse) for ADB macs: Dr. Bott's & Black Box.

The latter is rackmounted. I have seen 4-, 6- and 10-port varieties. They are heavy and bulky. The Dr. Bott's are heavy and compact.

My 6-port Black Box has the nr. 724-746-5500 on the front.
12 port also

DSCN0871.JPG

Posted by: ArmorAlley on 2020-03-14 14:23:02
12 port also
Nice (and relatively) compact too. Mine is the same height, one third longer with a simple knob in the middle.

Posted by: badCaps on 2020-03-14 14:33:48
As I posted it works great (therefore no caveats and it works as expected).  I'm not live switching - I only use one machine at a time so I switch to the machine I'm using and turn it on). As you might guess, when I want to switch, I turn that machine off, turn the dial and turn the next machine on.  I'm not sure why that would cause any concern? 
I must have mis-read, thought you were live switching like a KVM.  That 4 port would work great for one machine on at a time.  Also found this 2 port version on ebay:

https://www.ebay.com/itm/2way-Port-jack-AB-manual-switch-box-SVHS-S-Video-Super-VHS-4pin-mini-din-female/123734333192

I'll have to keep an eye out for one of those KVM's.

Also, Belkin made a 2 port KVM for mac:

BELKIN OMNIView PS/2 Mac Adapter F1D080

https://www.ebay.com/itm/BELKIN-OMNIView-PS-2-Mac-Adapter-F1D080-/372972548164

I did find this thread where someone mentioned that the svideo switch boxes share a ground pin and could cause trouble. 





I suppose a caveat to using would be to make sure only one mac is powered on at a time, just like you mentioned.

Posted by: superjer2000 on 2020-03-14 16:05:50
I did find this thread where someone mentioned that the svideo switch boxes share a ground pin and could cause trouble. 





I think you missed that part of my post as I covered it for the switchbox I bought. 

Posted by: krishnadraws on 2020-03-14 16:21:29
Thanks! It's good to know that there are options. Ideally, I'd love to swap between Mac SE/30, Mac SE and my Apple IIGS. I don't mind having to shut machines off before switching input devices.

Posted by: beachycove on 2020-03-15 06:35:24
I have a couple of old ADB/ DB15 KVMs that are non-branded, and must be around 25+ years old. No shutting down is required on shifting to another machine. The only limitation I discover in using them is that large monitors do not work especially well with the old hardware. 640x480 works fine.

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