iPDS Mains Power input WARNING
Vale, Martyn
Hi All,
I was watching one of Scott’s excellent iPDS videos last night and it reminded me to post something about the iPDS Mains input socket I discovered by accident coupled with a fair bit of smoke !
I’ve no idea if this is an already known issue or not, but just in case here’s the info:
The iPDS has an IEC C14 mains power inlet receptacle on the rear panel and for some reason Intel at least on my iPDS decided to incorporate interference suppression directly on the back of the socket and guess what they used………….well it had to be didn’t it 2 x RIFA Capacitors ! The issue is that the RIFA Capacitors are live as soon as power is applied to the input socket, the power is NOT isolated by either the Power Switch or Fuse, the upshot of this is that if you leave your iPDS connected to Mains Power even if it is off these capacitors are a ticking time bomb and will eventually crack or possibly explode emitting a fair quantity of smoke. The capacitors are hidden behind a black boot on the rear of the socket, so aren’t immediately visible.
My recommendation is that these capacitors are replaced or at least removed and until this is done DO NOT leave your iPDS plugged in to mains power unattended.
Bye
Martyn.
Herbert Johnson
S-100 desktop computers. As with all vintage computers, they simply were
not designed to work half a century later. Components fail with age.
Components connected to AC mains have the most risk of power overload.
A less appreciated fact: AC power voltages in the US may be 120V or
slightly above in some locations: 110V or lower was not uncommon decades
ago. Many vintage computers had transformer settings for below 110V AC
voltages. Higher voltage, more stress.
The immediately safest remedy is to disconnect the AC power cord *at the
back of the unit* when not in use, as Martyn notes. Do this immediately
after AC switch shutdown. Done as a habit it become automatic, as it is
for me with my Z-100 setup.
Another safety habit in the vintage computing shop, is to power all
equipment from an AC power strip, and to *power down the AC strip* when
work is done in the shop.
It might be useful to identify for the iPDS, a modern replacement IEC
module with the same form-factor. It may be useful generally, to
identify a IEC power cord with an AC switch near the computer end. The
Z-100 has a discrete AC filter, so AC filter caps can be replaced. I
don't know if the ips-100 and similar units have repairable receptacles.
regards Herb
On 1/12/2025 6:21 AM, Vale, Martyn wrote:
>
> The iPDS has an IEC C14 mains power inlet receptacle on the rear panel
> a fair quantity of smoke.
> removed and until this is done DO NOT leave your iPDS plugged in to
> mains power unattended.
Herb Johnson, New Jersey USA
http://www.retrotechnology.com or .net
preserve and restore 1970's personal computing
email: hjohnson @ retrotechnology dot com
or try later at herbjohnson @ comcast dot net
