Soldering and soldering and soldering and soldering

MOST PARTS ARE HERE

Four shipments are still outstanding, assuming I don't have to buy any additional parts. It should be only a few more days until the last arrives and I doubt I will be done with the soldering and assembly before then since it is a filler task when taking a break from my main restoration tasks. 

WORKAROUND FOR UNOBTAINIUM COMPONENTS

Several parts are completely sold out at all the parts distributors with forecast availability out into the summer. For the negative voltage regulators (-5 and -15V) the surface mount (DPAK) versions are the issue, while the more usual through hole parts are more attainable. One of the two regulators was not even available in through hole from distributors but I found a more trustworthy US based eBay seller who offered chips pulled from recycled systems, so I bought from them. 

Since the order of the three leads is the same between the two form factors and I have a large ground plane zone where the surface mount part would be soldered to transfer heat, I could solder down the tab which normally bolts to a heat shield, after bending and clipping the through hole leads to form legs to solder to the three surface pads. A bit ugly but it works.

SOLDERING AWAY IN MY FREE TIME

I have all the surface mount capacitors installed on the main board and most of the resistors. I expect to complete all the surface mount parts on the main board within the next day or two. At that point I move on to the through hole components until I have the board completed and ready for initial testing.

The front board got some attention from me as well. I have more capacitors, resistors, transistors, diodes and integrated circuits soldered down. There are still quite a few remaining. 

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