Uhh not pretty anymore
A couple of days ago my 4957A arrived from Frances. It worked for a few minutes until the Schaffer line filter exploded quite impressively.
You can see the dirt around the emergency pressure hole at the top. Saying this it was clear that I again have to order at DigiKey (they are the only ones with the same (?) line filter on stock) and it will become the next full restoration.
You can see some impressions of the accumulated dirt in the picture above and below. This machine has a lot of hours on it and needs some love.
There was a so a brightness fault when I first powered up the device – but I repaired itself after some seconds.
Either there was something wrong because of shipment or I touched the right spots in the device. However this needs further analysis.
The picture also was not clear and the pixel were bleeding out to the right – lets see if this gets better when cleaned and the caps are known good.
I got BTW a A0002 version device which means it should have the 80-characters VT100 terminal emulation.
What has to be done?
There is a lot on the list:
- Cleaning everything,
- Resoldering all connectors,
- Re-capping the whole device including exchanging the RIFAs,
- Changing the fan again as this one is even more noisy than the original 4951C one
- Build a replacement battery according to Curious Marcs recipe
What’s next?
Hopefully my super-cheapo spot-welder from amazon arrives today and Digi Key delivers as well – there will be some time at the upcoming weekend!
Stay tuned, I will document the work in the next article.