12-11-2019, 02:24 PM
(12-11-2019, 11:51 AM)Terry Wrote: As for the 'surface mount' PCB arrangement, I think there is a very simple answer.
Take another look at it and visualise it with the print on the underside.
Now work out how you would gain access to it to replace a faulty component ...
No, I'm sticking with my first theory - ease of production.
If that PCB was the other way up, then to replace a failed component, you'd simply have to snip it close to its body, leaving the wires in situ. A bodge, but we've all done it. I don't see anything that can't be changed that way - no radial components, etc.
Besides, if they really cared about serviceability, then all those components would be attached to pins or turrets, thus eliminating the very real risk of the print lifting when a hot soldering iron gets within a foot of the board (as they did back then). That would have avoided the problem with that big green cap too...
Of course, there is an outside chance the PCB is actually double-sided. It doesn't look like it, but you never know.
Actually, I reckon that flipping that PCB would be a darn sight easier than flipping the switch PCB in a Roberts R707 - far fewer components and wires to temporarily disconnect. Just one example - I can think of many others...
Not thinking about a possible future repair is hardly a modern disease. Getting it built and out of the door is all that counts.
