Mini S-100 chassis........Re: [N8VEM-S100:7458] Playing with FP Mini, Crustys 8080, Con I/O & SMB

[Dan Roganti]

​
[snip]
​
when installed in my
'Mini' system, just FF for the instruction.
Todd

​I was looking to get a chassis to build a mini S-100 system. I bought a
few of the S-100 backplanes that Josh & Todd made a few weeks ago. But I'm
still looking for a chassis.

Which kind of mini S-100 chassis would you have ?

I did find a set of SMPS's like John Monahan mentioned on his website for
his custom S-100 chassis. These are the kind with the variable voltage on
the output. So you don't have to remove the existing voltage regulators​ on
original boards or even the new boards. So I have +9v, +15v and -15v, then
I just turn down the +9v down a little to 8.5v, and turn up the +/-15v to
+/- 15.5v.

​Dan
​

[Wayne Talbot]

I also am looking for a S-100 chasis.
Wayne

Post by Dan Roganti

​
[snip]
​
when installed in my
'Mini' system, just FF for the instruction.
Todd

​I was looking to get a chassis to build a mini S-100 system. I bought a
few of the S-100 backplanes that Josh & Todd made a few weeks ago. But I'm
still looking for a chassis.
Which kind of mini S-100 chassis would you have ?
I did find a set of SMPS's like John Monahan mentioned on his website for
his custom S-100 chassis. These are the kind with the variable voltage on
the output. So you don't have to remove the existing voltage regulators​ on
original boards or even the new boards. So I have +9v, +15v and -15v, then
I just turn down the +9v down a little to 8.5v, and turn up the +/-15v to
+/- 15.5v.
​Dan
​
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[Bob Bell]

Dan, FYI


If you want to run 5V on the bus instead of 8V, you really don’t have to remove the regulators (yeah, that sound like an annoying job). Just solder a jumper wire from input to output, then be sure you mark the board VERY carefully so you don’t put it into an 8V backplane. In this configuration, the regulators draw a very nominal quiescent current that is significantly lower than anything else on the board. I run many boards like this in two S-100 computers. I use a MeanWell QP-200F switcher that has been adequate for both machines, one a 12-slot and the other an 8-slot. I no longer heat my basement with these computers, and sans that boat anchor power transformer and filter caps, I can actually LIFT them now without getting a hernia. Now if I could just get those IDE/CF boards built and working so the 8” floppy drives could go onto a shelf
 (Please, no help needed at this time on the IDE/CF card – I just need to find the time to work on the.)



Bob Bell





From: n8vem-***@googlegroups.com [mailto:n8vem-***@googlegroups.com] On Behalf Of Dan Roganti
Sent: Monday, July 27, 2015 1:32 PM
To: n8vem-***@googlegroups.com
Subject: Mini S-100 chassis........Re: [N8VEM-S100:7458] Playing with FP Mini, Crustys 8080, Con I/O & SMB



On Mon, Jul 27, 2015 at 12:48 PM, <***@mchsi.com> wrote:

​

[snip]

​

when installed in my
'Mini' system, just FF for the instruction.

Todd



​I was looking to get a chassis to build a mini S-100 system. I bought a few of the S-100 backplanes that Josh & Todd made a few weeks ago. But I'm still looking for a chassis.

Which kind of mini S-100 chassis would you have ?


I did find a set of SMPS's like John Monahan mentioned on his website for his custom S-100 chassis. These are the kind with the variable voltage on the output. So you don't have to remove the existing voltage regulators​ on original boards or even the new boards. So I have +9v, +15v and -15v, then I just turn down the +9v down a little to 8.5v, and turn up the +/-15v to +/- 15.5v.

​Dan
​

[l***@mchsi.com]

Both my S100 computers have switcher(s)

They are light weight, efficient and run cool.

My original Imsai's power supply was damaged in
shipping, so I replaced it with switcher(s)

You purists can roll over in your grave, but I sold
the damaged linear on Ebay to Todd Fischer.

The Mini I have been working on is a bit smaller;

https://sites.google.com/site/litterbox99/


Todd

----- Original Message -----
From: "Bob Bell" <***@gmail.com>
To: n8vem-***@googlegroups.com
Sent: Monday, July 27, 2015 3:32:42 PM
Subject: RE: Mini S-100 chassis........Re: [N8VEM-S100:7462] Playing with FP Mini, Crustys 8080, Con I/O & SMB

Dan, FYI…

If you want to run 5V on the bus instead of 8V, you really don’t have to remove the regulators (yeah, that sound like an annoying job). Just solder a jumper wire from input to output, then be sure you mark the board VERY carefully so you don’t put it into an 8V backplane. In this configuration, the regulators draw a very nominal quiescent current that is significantly lower than anything else on the board. I run many boards like this in two S-100 computers. I use a MeanWell QP-200F switcher that has been adequate for both machines, one a 12-slot and the other an 8-slot. I no longer heat my basement with these computers, and sans that boat anchor power transformer and filter caps, I can actually LIFT them now without getting a hernia. Now if I could just get those IDE/CF boards built and working so the 8” floppy drives could go onto a shelf… (Please, no help needed at this time on the IDE/CF card – I just need to find the time to work on the.)



Bob Bell





From: n8vem-***@googlegroups.com [mailto:n8vem-***@googlegroups.com] On Behalf Of Dan Roganti
Sent: Monday, July 27, 2015 1:32 PM
To: n8vem-***@googlegroups.com
Subject: Mini S-100 chassis........Re: [N8VEM-S100:7458] Playing with FP Mini, Crustys 8080, Con I/O & SMB



On Mon, Jul 27, 2015 at 12:48 PM, <***@mchsi.com> wrote:

​

[snip]

​

when installed in my
'Mini' system, just FF for the instruction.

Todd



​I was looking to get a chassis to build a mini S-100 system. I bought a few of the S-100 backplanes that Josh & Todd made a few weeks ago. But I'm still looking for a chassis.

Which kind of mini S-100 chassis would you have ?


I did find a set of SMPS's like John Monahan mentioned on his website for his custom S-100 chassis. These are the kind with the variable voltage on the output. So you don't have to remove the existing voltage regulators​ on original boards or even the new boards. So I have +9v, +15v and -15v, then I just turn down the +9v down a little to 8.5v, and turn up the +/-15v to +/- 15.5v.

​Dan
​

[Dan Roganti]

Post by Bob Bell
Dan, FYI

If you want to run 5V on the bus instead of 8V, you really don’t have to
remove the regulators (yeah, that sound like an annoying job). Just solder
a jumper wire from input to output, then be sure you mark the board VERY
carefully so you don’t put it into an 8V backplane. In this configuration,
the regulators draw a very nominal quiescent current that is significantly
lower than anything else on the board.

​oh yea, that was my first plan. Then I remembered something about John
Monahan's custom S-100 chassis on his website ​and saw the trick he did -
so I went with that instead.

I'm still looking for something to use as a Mini S-100 chassis. I found
some possibilities, just have to double check the dimensions. This is using
the new 9slot backplane from Josh/Todd plus those switching power supplies.
Also, it's always going to involve some bit of customizing to bolt
everything inside it.
Dan