Unstable when attaching mains

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cha05e90
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Joined: Mon Mar 14, 2022 1:31 pm

Unstable when attaching mains

Post by cha05e90 »

Hello!

I thought it might be a good idea to attach a mains adapter to my Z88 while exchanging data with my WIN box via Eazylink2 (I suppose the serial connection needs some energy... :-)). While attaching the mains adapter (the "newer" original Cambridge Computer plug-in power supply) the Z88 went into a "soft reset".

Because this is of course more than 30 years old, I tried a brand new "after market" mains adapter (CJE) - but this triggerd a "soft reset" as well. After some investigation it seems (regardless which adapter or plug in order) that every 4th or 5th connection triggers a soft reset and one out of ten even "freezes" the Z88 completely - only a "hard reset" can save it from that state.

Is there anything I'm doing wrong here or might this be (a known?) defect of my Z88?
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g7mmj
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Re: Unstable when attaching mains

Post by g7mmj »

Mine does the same. I suspect it may be down to elderly capacitors in need of replacement but I haven't investigated yet.

Steve
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1024MAK
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Re: Unstable when attaching mains

Post by 1024MAK »

Are you connecting while it’s on or when it’s asleep?

Mark
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cha05e90
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Re: Unstable when attaching mains

Post by cha05e90 »

1024MAK wrote: Wed Jun 22, 2022 11:13 am Are you connecting while it’s on or when it’s asleep?

Mark
I tried both variants and (just a "feeling") connecting while asleep seems to trigger the problems a littlebit more often...
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