Non clicky HP41 key

[ElectroDuende]

(07-14-2015 05:26 PM)Geoff Quickfall Wrote:  -LCD: cleaning, best way, desolder at the PCA side, then damp cotton cloth to clean underside of lens and the top side of the LCD. Place bracket and panel back, solder the far left or right contact in place, observe alignment-adjust and when satisfied solder the other far right or left contact thus securing the alignment at the opposite ends. Check again!!! Then solder remaining points. I use a three aa battery solder iron with fine point, very hot but for a short period and use flux.

Hum... I may try this, if I find a bit of time and quietness at home (difficult with two little beasts arround).

(07-14-2015 05:26 PM)Geoff Quickfall Wrote:  -keys: fixing domes involves removing all the heat stake tops (NOT ADVISED FOR THE FAINT HEARTED) sorry for the shouting. The hard part is leaving enough of the heat stake behind to remelt a cap. The REALLY hard part is soldering a replacement dome from a donor into place. Repairing the dome with solder has been tried but will fatigue very quickly. My suggestion is to live with it if still contacts. I know, not satisfying but what can you do? Getting a bouncing key repaired involves a drop of deoxit gold introduced into the tiny 'pore' associated with the offending key and then simply; pressing the key repeatedly. Deoxit actively restores the contact and removes corrosion, then protects the contact. It will fix the continuity problem but will not fix a cracked dome; which is the reason for no click.

That is what I feared... ok, for the moment I'll keep it like that, as it only misses one keystroke from time to time... maybe I'll try the deoxit option, to see if it improves this. That is why I feared about the golden nuts, as I have to remove the logic board to reach the pinhole of [3].

Many many thanks fur such a detailed explanation. You can count with a customer for your book here ;-)