ARCHIVED FORUM -- March 2012 to February 2022READ ONLY FORUM
This is the second Archived Forum which was active between 1st March 2012 and 23rd February 2022
Hi all,
I have been using a couple of Pentas Mk I as TV speakers, using the headphone amp in the TV to drive them. I'm not really happy with that, so I have started working on a better setup, where among other things the displays will be used.
So, I figured I should take a look at the displays, and this is what I found:
The voltage regulator has obviously been very hot:
On one of the boards the regulator had almost completely desoldered one of its legs:
The electrolytics definitely need to be replaced as well as the voltage regulators. What about the rectifier, is that likely to have taken a hit too? And what about the darlingtons (IC4 etc.) on the opposite board?
They've obviously been exposed to some heat.. Are those likely to be up for retirement?
Cheers
/ Johan
That brown Pertinax PCB material doesn't need much heat to darken with the years. Unless it is outright charred, that seems quite normal to me. If the displays worked, I don't think there's any reason to replace any other components than the electrolytic capacitors. Of course repair any bad or dubious solder joints; easiest to just reflow them all as there aren't that many.
--mika
Ok, cool. I might replace the regulator anyway, just to be on the safe side.
Thanks!
Johan: Ok, cool. I might replace the regulator anyway, just to be on the safe side. Thanks! / Johan
I would leave the reg and concentrate on reflow like Mika says - I can see at least 4 dry joints and the regulator terminal could do with a bit of solder!
Olly
Step1: I would leave the reg and concentrate on reflow like Mika says - I can see at least 4 dry joints and the regulator terminal could do with a bit of solder!
Sure, I will do that. I figured that the regulator terminal had been heated to the point where it has unsoldered itself, and that's why I thought I would replace it. But perhaps it's just bad soldering and not heat that has caused it? Would you expect the board to be more burnt if it had gotten that hot?